Ready For Takeoff - Turn Your Aviation Passion Into A Career

The Ready For Takeoff podcast will help you transform your aviation passion into an aviation career. Every week we bring you instruction and interviews with top aviators in their field who reveal their flight path to an exciting career in the skies.
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Jul 29, 2019

Lisa Marranzino was a therapist in Denver when she realized something was missing in her life. It might have been mid-life crisis. Whatever it was, she decided to explore the world and find what made people happy, both for herself and her patients.

That started a five-year odyssey in which she traveled to over 40 countries, spoke to scores of strangers in intimate conversations, and tried to find a common theme to what brings people happiness in all cultures.

She documented her conversations in her book, Happiness On The Blue Dot.


In this podcast, Lisa shares her experiences as a world traveler, and offers suggestions for interacting with strangers from around the world.

Jul 25, 2019

Operations Specifications (OPSPECS) are the specifications that the FAA assigns to airlines for such things as authorized routes, types of equipment, VFR and IFR operations, and alternate requirements.

OPS Spec C055 discusses the requirement for alternate airports.


One area that  is sometimes difficult for new Part 121 pilots to comprehend is the exclusivity of takeoff minimums from landing minimums. Try to picture each as completely separate from the other. Just because a particular airport is below landing minimums doesn’t (necessarily) mean you can’t depart. Instead, first attempt to consider the takeoff minimums by themselves. If the weather, airport equipment, aircraft capabilities, and FARs/Ops Specs will permit such a takeoff, nothing prevents you from departing. Only after you’ve examined the feasibility of a takeoff should you look at the landing minimums.

What if the airport is below landing mins? Then you’re required to have a takeoff alternate as outlined in 14 CFR 121.617. The exact weather mins for the takeoff alternate will be specified in the Ops Specs. In nearly all cases, your company Ops Specs will state the engine-inop, still-air distance in nautical miles (NMs); thus giving you an idea of the acceptable radius for an appropriate alternate.


121.617b says the takeoff alternate has to meet the alternate minimums in the Ops Specs. Paragraph C55 is the create your own minimums paragraph based on the available approaches. Pretty much for one approach add 400 and 1 to the mins and for 2 approaches, 200 and a half to the higher minimuns. The approaches have to be to different runways unless you're ETOPS, then they have to be to separate runways. If you're good for CAT III and the airport has dual CAT III runways you can get your alternate minimums down to 200/1800RVR. If it was down to that, I'd see about having a second alternate added to the release.

Jul 18, 2019

United Airlines Flight 232 was a regularly scheduled United Airlines flight from Denver to Chicago, continuing to Philadelphia. On July 19, 1989, the DC-10 (registered as N1819U) serving the flight crash-landed at Sioux City, Iowa, after suffering a catastrophic failure of its tail-mounted engine, which led to the loss of many flight controls. At the time, the aircraft was en route from Stapleton International Airport to O'Hare International Airport. Of the 296 passengers and crew on board, 111 died in the accident and 185 survived, making the crash the fifth-deadliest involving the DC-10, behind Turkish Airlines Flight 981, American Airlines Flight 191, Air New Zealand Flight 901, and UTA Flight 772. Despite the deaths, the accident is considered a prime example of successful crew resource management because of the large number of survivors and the manner in which the flight crew handled the emergency and landed the airplane without conventional control.

The airplane, a McDonnell Douglas DC-10-10 (registration N1819U), was delivered in 1973 and had been owned by United Airlines since then. Before departure on the flight from Denver on July 19, 1989, the airplane had been operated for a total of 43,401 hours and 16,997 cycles (a takeoff and subsequent landing is considered an aircraft cycle). The airplane was powered by CF6-6D high-bypass-ratio turbofan engines produced by General Electric Aircraft Engines (GEAE).

Captain Alfred Clair Haynes, 57, was hired by United Airlines in 1956. He had 29,967 hours of total flight time with United Airlines, of which 7,190 were in the DC-10.

First Officer William Roy Records, 48, was hired by National Airlines in 1969. He subsequently worked for Pan American World Airways. He estimated that he had approximately 20,000 hours of total flight time. He had 665 hours as a DC-10 first officer.

Second Officer Dudley Joseph Dvorak, 51, was hired by United Airlines in 1986. He estimated that he had approximately 15,000 hours of total flying time. He had 1,900 hours as a second officer in the Boeing 727 and 33 hours as a second officer in the DC-10.

Training Check Airman Captain Dennis Edward Fitch, 46, was hired by United Airlines in 1968. He estimated that, prior to working for United, he had accrued at least 1,400 hours of flight time with the Air National Guard, with a total flight time of approximately 23,000 hours. His total DC-10 time with United was 3,079 hours, of which 2,000 hours were accrued as a second officer, 1,000 hours as a first officer, and 79 hours as a captain. He had learned of the crash of Japan Airlines Flight 123, caused by a catastrophic loss of hydraulic control, and had wondered if it was possible to control an aircraft using throttles only. He had practiced under similar conditions on a simulator.

Flight 232 took off at 14:09 CDT from Stapleton International Airport, Denver, Colorado, bound for O'Hare International Airport in Chicago with continuing service to Philadelphia International Airport.

At 15:16, while the plane was in a shallow right turn at 37,000 feet, the fan disk of its tail-mounted General Electric CF6-6 engine explosively disintegrated. Debris penetrated the tail in numerous places, including the horizontal stabilizer, puncturing the lines of all three hydraulic systems.

The pilots felt a jolt, and the autopilot disengaged. As Records took hold of his control column, Haynes focused on the tail engine, whose instruments indicated it was malfunctioning; he found its throttle and fuel supply controls jammed. At Dvorak's suggestion, a valve cutting fuel to the tail engine was shut off. This part of the emergency took 14 seconds.

Meanwhile, Records found that the plane did not respond to his control column. Even with the control column turned all the way to the left, commanding maximum left aileron, and pulled all the way back, commanding maximum up elevator – inputs that would never be used together in normal flight – the aircraft was banking to the right with the nose dropping. Haynes attempted to level the aircraft with his own control column, then both Haynes and Records tried using their control columns together, but the aircraft still did not respond. Afraid the aircraft would roll into a completely inverted position (an unrecoverable situation), the crew reduced the left wing-mounted engine to idle and applied maximum power to the right engine. This caused the airplane to slowly level out.

The various gauges for all three hydraulic systems were registering zero. The three hydraulic systems were separate, so that failure of any one of them would leave the crew with full control, but lines for all three systems shared the same narrow passage through the tail where the engine debris had penetrated, and thus control surfaces were inoperative. The crew contacted United maintenance personnel via radio, but were told that, as a total loss of hydraulics on the DC-10 was considered "virtually impossible", there were no established procedures for such an event.

The plane was tending to pull right, and slowly oscillated vertically in a phugoid cycle – characteristic of planes in which control surface command is lost. With each iteration of the cycle, the aircraft lost approximately 1,500 feet (460 m) of altitude. On learning that Fitch, an experienced United Airlines captain and DC-10 flight instructor, was among the passengers, the crew called him into the cockpit for assistance.

Haynes asked Fitch to observe the ailerons through the passenger cabin windows to see if control inputs were having any effect. Fitch reported back that the ailerons were not moving at all. Nonetheless, the crew continued to manipulate their control columns for the remainder of the flight, hoping for at least some effect. Haynes then asked Fitch to take over control of the throttles so that Haynes could concentrate on his control column. With one throttle in each hand, Fitch was able to mitigate the phugoid cycle and make rough steering adjustments.

As the crew began to prepare for arrival at Sioux City, they questioned whether they should deploy the landing gear or belly-land the aircraft with the gear retracted. They decided that having the landing gear down would provide some shock absorption on impact.The complete hydraulic failure left the landing gear lowering mechanism inoperative. Two options were available to the flight crew. The DC-10 is designed so that if hydraulic pressure to the landing gear is lost, the gear will fall down slightly and rest on the landing gear doors. Placing the regular landing gear handle in the down position will unlock the doors mechanically, and the doors and landing gear will then fall down into place and lock due to gravity. An alternative system is also available using a lever in the cockpit floor to cause the landing gear to fall into position. This lever has the added benefit of unlocking the outboard ailerons, which are not used in high-speed flight and are locked in a neutral position. The crew hoped that there might be some trapped hydraulic fluid in the outboard ailerons and that they might regain some use of flight controls by unlocking them. They elected to extend the gear with the alternative system. Although the gear deployed successfully, there was no change in the controllability of the aircraft.

Landing was originally planned on the 9,000-foot (2,700 m) Runway 31. Difficulties in controlling the aircraft made lining up almost impossible. While dumping some of the excess fuel, the plane executed a series of mostly right-hand turns (it was easier to turn the plane in this direction) with the intention of lining up with Runway 31. When they came out they were instead lined up with the shorter (6,888 ft) and closed Runway 22, and had little capacity to maneuver. Fire trucks had been placed on Runway 22, anticipating a landing on nearby Runway 31, so all the vehicles were quickly moved out of the way before the plane touched down. Runway 22 had been permanently closed a year earlier.

ATC also advised that I-29 ran North and South just East of the airport which they could land on if they did not think they could make the runway. The pilot opted to try for the runway instead.

The plane landed askew, causing the explosion and fire seen in this still from local news station video.

Fitch continued to control the aircraft's descent by adjusting engine thrust. With the loss of all hydraulics, the flaps could not be extended and since flaps control both the minimum required forward speed and sink rate, the crew were unable to control both airspeed and sink rate. On final descent, the aircraft was going 220 knots and sinking at 1,850 feet per minute (approximately 407 km/h forward and 34 km/h downward speed), while a safe landing would require 140 knots and 300 feet per minute (approximately 260 km/h and 5 km/h respectively). Fitch needed a seat for landing; Dvorak offered up his own, as it could be moved to a position behind the throttles. Dvorak sat in the cockpit's jump seat for landing. Fitch noticed the high sink rate and that the plane started to yaw right again, and pushed the throttles to full power in an attempt to mitigate the high sink rate and level the plane.

There was not enough time for the flight crew to react. The tip of the right wing hit the runway first, spilling fuel, which ignited immediately. The tail section broke off from the force of the impact, and the rest of the aircraft bounced several times, shedding the landing gear and engine nacelles and breaking the fuselage into several main pieces. On the final impact, the right wing was shorn off and the main part of the aircraft skidded sideways, rolled over onto its back, and slid to a stop upside-down in a corn field to the right of Runway 22. Witnesses reported that the aircraft "cartwheeled" end-over-end, but the investigation did not confirm this. The reports were due to misinterpretation of the video of the crash that showed the flaming right wing tumbling end-over-end and the intact left wing, still attached to the fuselage, rolling up and over as the fuselage flipped over.

Jul 15, 2019

Tiffany Behr comes from a long line of military aviators, and was introduced to flying at an early age when she want flying with her father.

She attended Kansas University and then entered Air Force Undergraduate Pilot training at Laughlin Air Force Base in Del Rio, Texas. Her initial flying assignment was to C-130s, where she deployed on combat missions in Afghanistan.

Her next flying assignment was in the RC-135, OC-135 and WC-135. Following that, she was selected to fly Presidential Support missions in the 89th Military Airlift Squadron.

Next, she was selected to be a speech-writer for high-ranking officers in the Middle East.

After Tiffany left active duty she was hired by a major legacy airline, where she currently flies B737 NG aircraft.

Jul 11, 2019

A tail strike can occur during either takeoff or landing. Many air carrier aircraft have tail skids to absorb energy from a tailstrike. On some aircraft, the tail skid is a small bump on the aft underside of the airplane, while on others it is a retractable skid that extends and retracts with the landing gear.

Most tail strikes are the result of pilot error, and in general, landing tail strikes cause more damage than takeoff tail strikes.

In 1978, Japan Airlines flight 115 experienced a tail strike during landing that caused damage to the aft pressure bulkhead. The aircraft was repaired (although the repair was faulty) and returned to service. Seven years later, the aircraft, operating as Japan Airlines Flight 123, crashed as a result of the failure of the improperly-repaired pressure bulkhead.

This Boeing document is an excellent analysis of tailstrikes. A portion of the document is reproduced below:

Takeoff Risk Factors
Any one of these four takeoff risk factors may precede a tail strike:

  • Mistrimmed stabilizer.
  • Rotation at improper speed.
  • Excessive rotation rate.
  • Improper use of the flight director.

A mistrimmed stabilizer occurring during takeoff is not common but is an experience shared at least once by almost every flight crew. It usually results from using erroneous data, the wrong weights, or an incorrect center of gravity (CG). Sometimes the information presented to the flight crew is accurate, but it is entered incorrectly either to the flight management system (FMS) or to the stabilizer itself. In any case, the stabilizer is set in the wrong position. The flight crew can become aware of the error and correct the condition by challenging the reasonableness of the load sheet numbers. A flight crew that has made a few takeoffs in a given weight range knows roughly where the CG usually resides and approximately where the trim should be set. Boeing suggests testing the load sheet numbers against past experience to be sure that the numbers are reasonable.

A stabilizer mistrimmed nosedown can present several problems, but tail strike usually is not one of them. However, a stabilizer mistrimmed noseup can place the tail at risk. This is because the yoke requires less pull force to initiate airplane rotation during takeoff, and the pilot flying (PF) may be surprised at how rapidly the nose comes up. With the Boeing-recommended rotation rate between 2.0 and 3.0 degrees per second (dps), depending on the model, and a normal liftoff attitude, liftoff usually occurs about four seconds after the nose starts to rise. (These figures are fairly standard for all commercial airplanes; exact values are contained in the operations and/or flight-crew training manuals for each model.) However, with the stabilizer mistrimmed noseup, the airplane can rotate 5 dps or more. With the nose rising very rapidly, the airplane does not have enough time to change its flight path before exceeding the critical attitude. Tail strike can then occur within two or three seconds of the time rotation is initiated.

If the stabilizer is substantially mistrimmed noseup, the airplane may even try to fly from the runway without control input from the PF. Before reaching Vr, and possibly as early as approaching V1, the nose begins to ride light on the runway. Two or three light bounces may occur before the nose suddenly goes into the air. A faster-than-normal rotation usually follows and, when the airplane passes through the normal liftoff attitude, it lacks sufficient speed to fly and so stays on the runway. Unless the PF actively intercedes, the nose keeps coming up until the tail strike occurs, either immediately before or after liftoff.

This situation can result in a tail strike and is usually caused by one of two reasons: rotation is begun early because of some unusual situation, or the airplane is rotated at a V
r that has been computed incorrectly and is too low for the weight and flap setting.

An example of an unusual situation discovered during the DPD examination was a twinjet going out at close to the maximum allowable weight. In order to make second segment climb, the crew had selected a lower-than-usual flap setting. The lower flap setting generates V speeds somewhat higher than normal and reduces tail clearance during rotation. In addition, the example situation was a runway length-limited takeoff. The PF began to lighten the nose as the airplane approached V1, which is an understandable impulse when ground speed is high and the end of the runway is near. The nose came off the runway at V1 and, with a rather aggressive rotation, the tail brushed the runway just after the airplane became airborne.

An error in Vr speed recently resulted in a trijet tail strike. The load sheet numbers were accurate, but somehow the takeoff weight was entered into the FMS 100,000 lb lower than it should have been. The resulting Vr was 12 knots indicated air speed (kias) slow. When the airplane passed through a nominal 8-deg liftoff attitude, a lack of sufficient speed prevented takeoff. Rotation was allowed to continue, with takeoff and tail strike occurring at about 11 deg. Verification that the load sheet numbers were correctly entered may have prevented this incident.

Flight crews operating an airplane model that is new to them, especially when transitioning from unpowered flight controls to ones with hydraulic assistance, are most vulnerable to using excessive rotation rate. The amount of control input required to achieve the proper rotation rate varies from one model to another. When transitioning to a new model, flight crews may not consciously realize that it will not respond to pitch input in exactly the same way.

As simulators reproduce airplane responses with remarkable fidelity, simulator training can help flight crews learn the appropriate response. A concentrated period of takeoff practice allows students to develop a sure sense of how the new airplane feels and responds to pitch inputs. On some models, this is particularly important when the CG is loaded toward its aft limits, because an airplane in this condition is more sensitive in pitch, especially during takeoff. A normal amount of noseup elevator in an aft CG condition is likely to cause the nose to lift off the runway more rapidly and put the tail at risk.

As shown in figure 1, the flight director (FD) is designed to provide accurate pitch guidance only after the airplane is airborne, nominally passing through 35 ft (10.7 m). With the proper rotation rate, the airplane reaches 35 ft with the desired pitch attitude of about 15 deg and a speed of V
2 + 10 (V2 + 15 on some models). However, an aggressive rotation into the pitch bar at takeoff is not appropriate and may rotate the tail onto the ground.

Landing Risk Factors
Any one of these four landing risk factors may precede a tail strike:

  • Unstabilized approach.
  • Holding off in the flare.
  • Mishandling of crosswinds.
  • Over-rotation during go-around.

A tail strike on landing tends to cause more serious damage than the same event during takeoff and is more expensive and time consuming to repair. In the worst case, the tail can strike the runway before the landing gear touches down, thus absorbing large amounts of energy for which it is not designed. The aft pressure bulkhead is often damaged as a result.

An unstabilized approach appears in one form or another in virtually every landing tail strike event. When an airplane turns on to final approach with excessive airspeed, excessive altitude, or both, the situation may not be under the control of the flight crew. The most common cause of this scenario is the sequencing of traffic in the terminal area as determined by air traffic control.

Digital flight recorder data show that flight crews who continue through an unstabilized condition below 500 ft will likely never get the approach stabilized. When the airplane arrives in the flare, it invariably has either excessive or insufficient airspeed, and quite often is also long on the runway. The result is a tendency toward large power and pitch corrections in the flare, often culminating in a vigorous noseup pull at touchdown and tail strike shortly thereafter. If the nose is coming up rapidly when touchdown occurs and the ground spoilers deploy, the spoilers themselves add an additional noseup pitching force. Also, if the airplane is slow, pulling up the nose in the flare does not materially reduce the sink rate and in fact may increase it. A firm touchdown on the main gear is often preferable to a soft touchdown with the nose rising rapidly.

The second most common cause of a landing tail strike is a long flare to a drop-in touchdown, a condition often precipitated by a desire to achieve an extremely smooth landing. A very soft touchdown is not essential, nor even desired, particularly if the runway is wet.

Trimming the stabilizer in the flare may contribute to a tail strike. The PF may easily lose the feel of the elevator while the trim is running; too much trim can raise the nose, even when this reaction is not desired. The pitchup can cause a balloon, followed either by dropping in or pitching over and landing flat. Flight crews should trim the airplane in the approach, but not in the flare itself, and avoid "squeakers," as they waste runway and may predispose the airplane to a tail strike.

A crosswind approach and landing contains many elements that may increase the risk of tail strike, particularly in the presence of gusty conditions. Wind directions near 90 deg to the runway heading are often strong at pattern altitude, and with little headwind component, the airplane flies the final approach with a rapid rate of closure on the runway. To stay on the glidepath at that high groundspeed, descent rates of 700 to 900 ft (214 to 274 m) per minute may be required. Engine power is likely to be well back, approaching idle in some cases, to avoid accelerating the airplane. If the airplane is placed in a forward slip attitude to compensate for the wind effects, this cross-control maneuver reduces lift, increases drag, and may increase the rate of descent. If the airplane then descends into a turbulent surface layer, particularly if the wind is shifting toward the tail, the stage is set for tail strike.

The combined effects of high closure rate, shifting winds with the potential for a quartering tail wind, the sudden drop in wind velocity commonly found below 100 ft (31 m), and turbulence can make the timing of the flare very difficult. The PF can best handle the situation by exercising active control of the sink rate and making sure that additional thrust is available if needed. Flight crews should clearly understand the criteria for initiating a go-around and plan to use this time-honored avoidance maneuver when needed.

Go-arounds initiated very late in the approach, such as during flare or after a bounce, are a common cause of tail strike. When the go-around mode is initiated, the FD immediately commands a go-around pitch attitude. If the PF abruptly rotates into the command bars, tail strike can occur before a change to the flight path is possible. Both pitch attitude and thrust are required for go-around, so if the engines are just spooling up when the PF vigorously pulls the nose up, the thrust may not yet be adequate to support the effort. The nose comes up, and the tail goes down. A contributing factor may be a strong desire of the flight crew to avoid wheel contact after initiating a late go-around, when the airplane is still over the runway. In general, the concern is not warranted because a brief contact with the tires during a late go-around does not produce adverse consequences. Airframe manufacturers have executed literally hundreds of late go-arounds during autoland certification programs with dozens of runway contacts, and no problem has ever resulted. The airplane simply flies away from the touchdown.

Jul 8, 2019

Lt. Commander Dominique (Nikki) Selby was a Critical Care, Trauma and Enroute Care Nurse for the US Navy. She deployed to various regions to include Haiti, Afghanistan and various countries in the Middle East as an in-flight critical care nurse, ICU, trauma and Fleet Surgical Team nurse operating in austere conditions (Role II and Role III facilities). She is currently a Course Coordinator for the Advanced Trauma Course for Nurses and a Training Site Facilitator for ACLS, and teaches classes to all military and civilian providers for the Naval Medical Center San Diego.
Her current certifications are BLS-I, ACLS-I/TSF, ATCN Instructor and Course Coordinator, PALS-P, TCCC-P and TNCC-P. With 22 years in the Navy and 12 years of experience as an RN, she is certified in Emergency Nursing (CEN) and currently licensed in the states of Nevada and California. 


Jul 4, 2019

There are four types of Hypoxia:
Hypoxia means “reduced oxygen” or “not enough oxygen.”
Although any tissue will die if deprived of oxygen long
enough, the greatest concern regarding hypoxia during
flight is lack of oxygen to the brain, since it is particularly
vulnerable to oxygen deprivation. Any reduction in mental
function while flying can result in life-threatening errors.
Hypoxia can be caused by several factors, including an
insufficient supply of oxygen, inadequate transportation of
oxygen, or the inability of the body tissues to use oxygen.
The forms of hypoxia are based on their causes:
• Hypoxic hypoxia
• Hypemic hypoxia
• Stagnant hypoxia
• Histotoxic hypoxia
Hypoxic Hypoxia
Hypoxic hypoxia is a result of insufficient oxygen available
to the body as a whole. A blocked airway and drowning
are obvious examples of how the lungs can be deprived of
oxygen, but the reduction in partial pressure of oxygen at high
altitude is an appropriate example for pilots. Although the
percentage of oxygen in the atmosphere is constant, its partial
pressure decreases proportionately as atmospheric pressure
decreases. As an aircraft ascends during flight, the percentage
of each gas in the atmosphere remains the same, but there are
fewer molecules available at the pressure required for them
to pass between the membranes in the respiratory system.
This decrease in number of oxygen molecules at sufficient
pressure can lead to hypoxic hypoxia.

Hypemic Hypoxia
Hypemic hypoxia occurs when the blood is not able to take
up and transport a sufficient amount of oxygen to the cells
in the body. Hypemic means “not enough blood.” This type
of hypoxia is a result of oxygen deficiency in the blood,
rather than a lack of inhaled oxygen, and can be caused by
a variety of factors. It may be due to reduced blood volume
(from severe bleeding), or it may result from certain blood
diseases, such as anemia. More often, hypemic hypoxia
occurs because hemoglobin, the actual blood molecule that
transports oxygen, is chemically unable to bind oxygen
molecules. The most common form of hypemic hypoxia is
CO poisoning. This is explained in greater detail later in this
chapter. Hypemic hypoxia can also be caused by the loss
of blood due to blood donation. Blood volume can require
several weeks to return to normal following a donation.
Although the effects of the blood loss are slight at ground
level, there are risks when flying during this time.

Stagnant Hypoxia
Stagnant means “not flowing,” and stagnant hypoxia or
ischemia results when the oxygen-rich blood in the lungs
is not moving, for one reason or another, to the tissues that need it. An arm or leg “going to sleep” because the blood
flow has accidentally been shut off is one form of stagnant
hypoxia. This kind of hypoxia can also result from shock,
the heart failing to pump blood effectively, or a constricted
artery. During flight, stagnant hypoxia can occur with
excessive acceleration of gravity (Gs). Cold temperatures
can also reduce circulation and decrease the blood supplied
to extremities.

Histotoxic Hypoxia
The inability of the cells to effectively use oxygen is defined
as histotoxic hypoxia. “Histo” refers to tissues or cells, and
“toxic” means poisonous. In this case, enough oxygen is being
transported to the cells that need it, but they are unable to make
use of it. This impairment of cellular respiration can be caused
by alcohol and other drugs, such as narcotics and poisons.
Research has shown that drinking one ounce of alcohol can
equate to an additional 2,000 feet of physiological altitude.

Symptoms of Hypoxia
High-altitude flying can place a pilot in danger of becoming
hypoxic. Oxygen starvation causes the brain and other vital
organs to become impaired. The first symptoms of hypoxia
can include euphoria and a carefree feeling. With increased
oxygen starvation, the extremities become less responsive and
flying becomes less coordinated. The symptoms of hypoxia
vary with the individual, but common symptoms include:
• Cyanosis (blue fingernails and lips)
• Headache
• Decreased response to stimuli and increased reaction
• Impaired judgment
• Euphoria
• Visual impairment
• Drowsiness
• Lightheaded or dizzy sensation
• Tingling in fingers and toes
• Numbness
As hypoxia worsens, the field of vision begins to narrow and
instrument interpretation can become difficult. Even with all
these symptoms, the effects of hypoxia can cause a pilot to
have a false sense of security and be deceived into believing
everything is normal.

Treatment of Hypoxia
Treatment for hypoxia includes flying at lower altitudes and/
or using supplemental oxygen. All pilots are susceptible
to the effects of oxygen starvation, regardless of physical
endurance or acclimatization. When flying at high altitudes,
it is paramount that oxygen be used to avoid the effects of
hypoxia. The term “time of useful consciousness” describes
the maximum time the pilot has to make rational, life-saving
decisions and carry them out at a given altitude without
supplemental oxygen. As altitude increases above 10,000
feet, the symptoms of hypoxia increase in severity, and the
time of useful consciousness rapidly decreases. [Figure 17-1]
Since symptoms of hypoxia can be different for each
individual, the ability to recognize hypoxia can be greatly
improved by experiencing and witnessing the effects of it
during an altitude chamber “flight.” The Federal Aviation
Administration (FAA) provides this opportunity through
aviation physiology training, which is conducted at the FAA
CAMI in Oklahoma City, Oklahoma, and at many military
facilities across the United States. For information about the
FAA’s one-day physiological training course with altitude
chamber and vertigo demonstrations, visit the FAA website

Jul 1, 2019

Morri Leland is the Chief Executive Officer of Patriot Mobile.  He assumed the role of CEO in 2017.  

As CEO, Morri is focused on helping conservative consumers and businesses throughout the United States protect and defend their rights and liberty and ensure these freedoms remain for generations to come.

For more than 30 years, Morri has led global teams to excel and exceed growth expectations.  Prior to joining Patriot Mobile, he served as Deputy Vice President for International Business at Lockheed Martin Missiles and Fire Control, headquartered in Dallas, Texas. Morri was responsible for global sales and marketing for the aerospace, defense and energy sectors that included numerous competitive global pursuits that resulted in significant international growth.  Prior to that Morri served as the Program Director for F-35 / CVF Integration with Lockheed Martin Aeronautics.  As the senior representative for the Joint Strike Fighter program in the United Kingdom (UK), he was responsible for the successful development and management of the program to integrate the F-35 air system into the design and construction of the UK Future Aircraft Carrier (CVF).  

From 1983 to 2003, Morri served on active duty in the United States Navy.  After tours at NASA and as a flight instructor, he accumulated over 5,000 hours in various types of military aircraft.  With significant time in various models of the F/A-18 Hornet, he served multiple combat tours in Afghanistan, Iraq and the Balkans and commanded a squadron that garnered honors as the top Strike-Fighter squadron in the U.S. Navy.  He also served on a NATO exchange flying tour and in the Pentagon on the staff of the Chairman of the Joint Chiefs of Staff.

A native of South Carolina, Morri holds a BS in Systems Engineering from the U.S. Naval Academy and a Master of Science in International Security Affairs from the U.S. Naval War College.

Morri and his wife Sheila reside in Southlake, TX with their two sons.

Jun 27, 2019

From AVweb:
Pull the mixture or condition lever and the propeller comes to a stop. Turn off the switches and what had been saturated with noise and vibration becomes still and quiet. After removing your headset and while sitting in the momentary silence that follows a flight, perhaps you’ll hear the engine ticking as heat dissipates. It’s time to pack up and leave the cockpit: Your work is done, right? No, not quite. To get the full benefit of the experience you just had, to learn from every flight, you need to spend just a few moments debriefing your flight.

Your post-flight debrief doesn’t have to be detailed. Just ask yourself a few questions, and provide honest answers. Your briefing also can be very structured, with a personalized debriefing form and lists of the myriad tasks you performed or planned, plus a scoring mechanism to fairly and objectively judge your performance. The most effective way to debrief, and the most likely system that actually will get used is probably somewhere in between. Regardless of how you debrief, the objective is to review the manner in which you conducted the just-ended flight so you can learn from your actions and be even better next time you fly.

Most pilot and flight instructor texts give a passing nod to the post-flight briefing. Virtually all declare it to be a highly important part of the flight-training process. Most decry the “lecture” method, in which the instructor tells the student what he or she did right and in what areas he or she needs to improve. The consensus is that better results come from asking the student to critique his or her performance, with the discussion guided, but not totally led, by the flight instructor. The biggest obstacles to making this technique work, according to the FAA’s Flight Instructor Handbook, are the student’s lack of experience and objectivity, which result in an inability to properly assess his/her performance; the fatigue state of a student after a lesson, especially in the early stages of pilot training; and an instructor’s lack of familiarity with good debriefing techniques. Another factor is the instructor or student’s unwillingness to spend the time necessary to conduct a useful post-flight debriefing.

I’ve not yet found any FAA guidance on extending the concept of a post-flight briefing to a pilot who is critiquing his or her performance following a day-to-day, non-instructional flight. Yet the vast majority of our flying happens without an instructor by our side, and available to review the flight afterward. Although instructors present us the training needed to earn certificates and ratings, and occasionally provide a refresher in the form of a flight review, an instrument proficiency check (IPC) and other recurrent training, we learn most from our own experiences as pilot-in-command in real-world situations.

Psychologist and flight instructor Dr. Janet Lapp is a proponent of the post-flight self-brief. “What happens during the crucial period of time immediately following a behavior, or set of behaviors, can either reinforce (make stronger), punish (eliminate temporarily), or help extinguish (aid in forgetting) that behavior,” according to her November 2008 article in AOPA’s Flight Training magazine.

“The best time to learn may be in the few moments right after a flight, in an organized and controlled manner,” she wrote. “Actions completed by self, rather than by other, are more meaningful and memorable; memory traces are more indelibly etched; and content is more internalized. We become responsible for what we do…[and] we take more responsibility for our actions.”

Dr. Lapp suggests we commit our debriefings to writing, building a journal of our growing experience. “If we don’t measure it,” she writes, “we can’t change it.” Lapp also says her personal research suggests that a written review makes pilots open up to the process and give self-debriefing the attention it deserves. The “central purpose [of a written review] is to increase self-correction, reflection, and tracking of attitude and behaviors. The goal is to create pilots who reflect on emerging issues immediately after every flight. The students make the entries, specify what they did well and what they could have done better, what they will work on next time, and what knowledge gaps were discovered. These are accompanied by a self-rating system that creates its own system of improvement.”

Dr. Lapp makes her suggested debriefing form available to the public, and invites pilots to adopt it and customize it to their needs. It allows the pilot to identify the major areas of critique, and to answer a few broad questions that identify the overall tenor of the flight. Although Dr. Lapp’s research focused on students receiving instruction (which was, after all, when she was present to introduce the concept of the post-flight debrief and judge the results), she notes in the Flight Training article she created the form originally to reinforce her own need for post-flight debriefings as a certificated and active pilot, and has told me several times her intent is for pilots to use the form as a self-debriefing tool.

Some pilots have suggested reluctance to create a written record of the mistakes they’ve made while flying an airplane. They seem to fear the journal could “fall into the wrong hands” and be used in some way against them in an FAA enforcement action or a liability lawsuit. Sad to say, they may be right. If you choose not to maintain a written record, but you find the act of writing about and scoring your flights indeed does focus your attention on continual improvement, there’s nothing to prevent you from critiquing your performance in writing and then destroying the record when you’re done with it.

If you want to develop an even more detailed type of self-debriefing, you might do what I do as a result of my military experience. Back in the Bad Old Days of the Cold War, I served as a Minuteman nuclear missile launch control officer for the U.S. Air Force. The pressure-cooker environment of potential total nuclear war, 60 feet under the Missouri plains, strangely did much to prepare me for the single-pilot cockpit of an airplane. One thing the “missile business” did for me as a pilot was to teach the debriefing concept of minor, major and critical errors.

Air Force missileers train and are evaluated relentlessly. At least once a month we spent four hours in “the box”—a functional simulator reproducing the hardware and operation of a missile launch control center. No less than once a year we were evaluated in the box (I personally had eight “annual” checks during a four-year tour of duty—go figure). We also were evaluated “in the field”—observed while on actual alert—much like a line check for an airline pilot.

Every evaluation assumed from the beginning that the missile combat crew’s performance was perfect —earning 5.0 points on a five-point scale. Of course, from there, things can go only one direction: downhill. Certain functions, if performed incorrectly, were considered minor errors. These were items that were missed or performed incorrectly, but which did not directly impact the primary mission. Commit a minor error, and you’d have one-tenth of a point lopped off your beginning, perfect score.

A major error might delay getting a missile repaired correctly, allow unauthorized access to a missile site (but no direct access to controls, boosters or warheads), or cause (by action or inaction) one component of the hardware to become inoperative. A major error cost one full point off your final score. In some cases it was possible to recover from a minor or even some major errors, and not be charged the adverse points…if you caught the error in time, and undid what you had done.

A critical error in missiledom cost five points, an automatic failure of the evaluation. Examples of “crits” included attempting to launch missiles when not ordered, launching at a valid order but at the wrong time, or launching to the wrong targets, all of which are highly undesirable events (this was, of course, all in “the box”). In the field, critical error might be tuning a radio or satellite receiver incorrectly (meaning you would not receive emergency messages). Another critical error was to shut down your launch capsule when not called for, thereby degrading your squadron’s ability to launch missiles (usually, when dealing with a simulated fire in your tiny underground command center).

Error points were additive. A major error and two minor errors resulted in a 3.8 score, etc. A crew was deemed qualified if its final score was 2.5 or higher. Crewmembers were awarded highly qualified (HQ) status for a 4.6 or better score (no more than four minor errors, and none of the major ones). You could “crit out” on a combination of major and minor errors. And sometimes an action that would ordinarily only be a minor error (such as setting a clock or tuning a radio) might become “major” if that act led to missing some other task, or it might even be critical if it adversely affected alert status or a simulated launch later on. Great woe fell upon the combat crew that “critted out” and had to go through the entire crew certification procedure to regain their mission-ready status.

What’s this got to do with flying airplanes? Since we’re not talking nuclear Armageddon here, most pilots who “crit out” (i.e., have an accident) do so by letting minor and major errors snowball. Here’s an example from several years ago: I was flying a Beechcraft Bonanza from Wichita to Tullahoma, Tenn. This was my first long trip in the rented Beech, and I was still getting the hang of its Garmin GX60 IFR-qualified GPS. Somewhere over southwestern Missouri, I was assigned a vector around a newly hot MOA, and was told to expect direct to the Walnut Ridge VOR and then the rest of my route as filed. I made the heading change and began fiddling with the GPS.

Still not fully proficient with the interface, I put the Bonanza on autopilot while I loaded the new waypoints. Satisfied, I activated the flight plan…and watched as the Bo’ turned directly toward Walnut Ridge, about five degrees to my left. Minor error! I realized my mistake and returned to my assigned heading. I never penetrated the MOA, and ATC never said a word about it. I was now flying on a “4.9” score. I made a quick note to include the event after I landed, when I’d have time to learn from it. If I’d have accidentally penetrated the MOA, or if ATC had needed to divert traffic to avoid me as a result, it would have been a “major” offense. And if I’d hit something because of my originally “minor” transgression, well….

Some examples of minor errors: missing a radio call; failure to tune backup navcoms; improper setting of altitude alerters; misprogramming or failing to confirm the autopilot’s operating modes; one dot from center on course guidance or glidepath at the missed approach point; etc. A few examples of major errors: Missing a handoff; flying a destabilized approach; deviation from your fuel management schedule; more than 100 feet off altitude; etc. In addition to actual crashes, critical errors include: busting minimums; deviations from an instrument procedure, cleared route or altitude that would result in failure of the IFR Practical Test; failing to brief for the missed approach; failure to follow an obstacle departure procedure; etc. You could list possibilities all day long. It’s easier and more effective to quickly note the transgressions in flight, then rank errors against the minor/major/critical scale after you land.

The trick of flying is to minimize the minor errors and avoid the major offenses, and thereby not “crit out,” or have an accident. We will make mistakes. It’s almost always possible to recover from a minor error in the plane and keep your score in the HQ range. Even if you “pull a major,” as we said in the Air Force, you can fly the rest of the trip in perfect safety if you monitor your position, use your checklists and watch your performance. Put the emotion of making a mistake behind you, and fly the rest of the trip to HQ standards. After you land, review your in-flight notes and score yourself—to become a highly qualified pilot.

Whether you answer a few brief questions or complete a detailed, point-by-point review—in your head, aloud with a fellow pilot or in writing—to fully benefit from the experience of every flight it’s extremely helpful to do a post-flight debriefing. The sooner after you land the better, because more information will be fresh in your head.

Most of us shut down, get out of the airplane, and get on with our busy lives—likely the reason we flew in the first place. Taking a few moments, however, to review the lessons of every flight will help prepare you for the next ones.

Jun 24, 2019

Craig O'Mara didn't start out intending to be a pilot. He was a bird-watcher, and became more interested in flight as he watched the birds, and started flying as a teenager. He soloed as a 16-year old, and received his Private Pilot certificate on his 17th birthday.

In 1979 he joined the Air Force Reserves as a C-9 pilot, flying air ambulance missions all over the United States, as well as overseas. He flew the C-9 for a total of 20 years.

In 1985 he was hired by United Airlines, and served on the DC-10, B737, B757/767, B747 and B787. He was a Line Check Airman on many of these aircraft.

In addition to his United flying, Craig flew as a pilot for NASA in the B747SP. He also flew a variety of warbirds.

Jun 20, 2019

Your preflight briefing will depend on what type of flight you are planning - a training flight briefing will be quite different than an airline brief. But there are some factors that will be common to all flights:

Mission Objective



Aircraft Performance

Aircraft Maintenance Status

Route of Flight


Takeoff Briefing (PF)

Departure/Arrival Airports

Rejected Takeoff


Crew Member Duties/Expectations

Arrival/Approach/Missed Approach


Training Objective/Elements

Jun 17, 2019

Special thanks to Shreenand Sadhale for suggesting this episode!

Cliff Notes version of my career:

Air Force Academy

Undergraduate Pilot Training

O-2A Forward Air Controller, Danang, Vietnam

B-52 copilot, Mather Air Force Base

F-4 Aircraft Commander, Ubon Royal Thai Air Force Base

F-4 Aircraft Commander, Kadena Air Base, Okinawa

T-39 Aircraft Commander/Instructor Pilot, Kadeena Air Base, Okinawa

O-2A Instructor Pilot, Patrick Air Force Base, Florida

B727 Flight Operations Instructor/Flight Engineer, Unites Airlines

O-2A Instructor Pilot, Patrick Air Force Base, Florida

T-39/C-21 Instructor Pilot/Evaluator, Yokota Air Base, Japan

B737 First Officer/Training Check Airman, United Airlines

B737/B727 Captain, United Airlines

B727 /B777 Standards Captain, United Airlines

Adjunct Professor, Metropolitan State College of Denver/Embry-Riddle Aeronautical University

C680 Flight Instructor/Evaluator, FlightSafety International

B777 Senior Commander, Jet Airways, India

IOSA Audit Team Leader

B787 Instructor Pilot, Boeing

B777 Instructor Pilot, Omni Air International

Lecturer, Metropolitan State University of Denver

Fleet Technical Instructor, United Airlines

Jun 13, 2019

FAR 91.25 refers to the NASA Aviation Safety Reporting Program, and Advisory Circular AC 00-46E Explains the program. AOPA has an excellent article about the program.

The Aviation Safety Reporting System, or ASRS, is the US Federal Aviation Administration's (FAA) voluntary confidential reporting system that allows pilots and other aircraft crew members to confidentially report near misses and close calls in the interest of improving air safety. The ASRS collects, analyzes, and responds to voluntarily submitted aviation safety incident reports in order to lessen the likelihood of aviation accidents. The confidential and independent nature of the ASRS is key to its success, since reporters do not have to worry about any possible negative consequences of coming forward with safety problems. The ASRS is run by NASA, a neutral party, since it has no power in enforcement. The success of the system serves as a positive example that is often used as a model by other industries seeking to make improvements in safety.

A notable feature of the ASRS is its confidentiality and immunity policy. Reporters may, but are not required to, submit their name and contact information. If the ASRS staff has questions regarding a report, it can perform a callback and request further information or clarification from the reporter. Once the staff is satisfied with the information received, the report is stripped of identifying information and assigned a report number. The part of the reporting form with contact information is detached and returned to the reporter. ASRS will issue alerts to relevant parties, such as airlines, air traffic controllers, manufacturers or airport authorities, if it feels it is necessary to improve safety. The ASRS also publishes a monthly newsletter highlighting safety issues, and now has an online database of reports that is accessible by the public.

Often, reports are submitted because a rule was accidentally broken. The FAA's immunity policy encourages submission of all safety incidents and observations, especially information that could prevent a major accident. If enforcement action is taken by the FAA against an accidental rule violation that did not result in an accident, a reporter can present their ASRS form as proof that the incident was reported. The FAA views the report as evidence of a "constructive safety attitude" and will not impose a penalty.Immunity can be exercised once every five years, though an unlimited number of reports can be filed.

Due to the self-selected nature of the reports to the ASRS, NASA cautions against statistical use of the data they contain. On the other hand, they do express considerable confidence in the reliability of the reports submitted:

"However, the ASRS can say with certainty that its database provides definitive lower-bound estimates of the frequencies at which various types of aviation safety events actually occur. For example, 34,404 altitude overshoots were reported to the ASRS from January 1988 through December 1994. It can be confidently concluded that at least this number of overshoots occurred during the 1988-94 period--and probably many more. Often, such lower-bound estimates are all that decision makers need to determine that a problem exists and requires attention."[3]

Speaking before a Flight Safety Foundation International Air Safety Seminar in Madrid in November 1966, Bobbie R. Allen, the Director of the Bureau of Safety of the U.S. Civil Aeronautics Board, referred to the vast body of accumulated aviation safety incident information as a "sleeping giant." Noting that fear of legal liability and of regulatory or disciplinary action had prevented the dissemination of this information, rendering it valueless to those who might use it to combat hazards in the aviation system, Mr. Allen commented:

“In the event that the fear of exposure cannot be overcome by other means, it might be profitable if we explored a system of incident reporting which would assure a substantial flow of vital information to the computer for processing, and at the same time, would provide some method designed to effectively eliminate the personal aspect of the individual occurrences so that the information derived would be helpful to all and harmful to none.”

Several years earlier, in testimony before the U.S. Senate on the legislation proposing the Federal Aviation Act of 1958, the late William A. Patterson, then President of United Airlines, touched on the need to develop accurate safety trend information. "On the positive side," said Mr. Patterson, "you take your statistics - and your records - and your exposures - and you act before the happening!“

These distinguished aviation figures were articulating an objective long-recognized, but which had frustrated all efforts at accomplishment. In the years to come, frequent references to the need for information collection and dissemination would recur.

Enforcement Restrictions. The FAA considers the filing of a report with NASA concerning an incident or occurrence involving a violation of 49 U.S.C. subtitle VII or the 14 CFR to be indicative of a constructive attitude. Such an attitude will tend to prevent future violations. Accordingly, although a finding of violation may be made, neither a civil penalty nor certificate suspension will be imposed if:

  1. The violation was inadvertent and not deliberate;
  2. The violation did not involve a criminal offense, accident, or action under 49 U.S.C. §44709, which discloses a lack of qualification or competency, which is wholly excluded from this policy;
  3. The person has not been found in any prior FAA enforcement action to have committed a violation of 49 U.S.C. subtitle VII, or an regulation promulgated there for a period of 5 years prior to the date of occurrence; and
  4. The person proves that, within 10 days after the violation, or date when the person became aware or should have been aware of the violation, he or she completed and delivered or mailed a written report of the incident or occurrence to NASA.
Jun 10, 2019

Keith Reeves wanted to be a pilot ever since he was a child, living on base at Kadena Air Base, Japan, and hearing the local F-4s and SR-71s taking off.

When the family relocated to Selfridge Air Force Base he got the chance to get close to airplanes. A friend on base took him up for a flight in a General Aviation plane, and he was hooked.

He attended the United States Air Force Academy, and flew with the Academy aero club. Before Undergraduate Pilot Training, he served as an engineer at Wright-Patterson Air Force Base, then he attended pilot training at Laughlin Air Force Base. Kevin qualified for the T-38 track, then flew B-52's for 5 1/2 years, rising to the position of Instructor Pilot.

While flying B-52s, he bought a Citabria, and kept it for 10 years.

He applied to the B-2 program, and was accepted on his third attempt. He remained on the B-2 for the remainder of his flying career, stationed at Whiteman Air Force Base. In addition to the B-2, Keith was dual-qualified in the T-38.

During Operation Iraqi Freedom, he flew a 37-hour flight.

Keith now flies as a B737 first officer for a major legacy airline.

Jun 6, 2019

Operation Overlord was the codename for the Battle of Normandy, the Allied operation that launched the successful invasion of German-occupied Western Europe during World War II. The operation was launched on 6 June 1944 with the Normandy landings (Operation Neptune, commonly known as D-Day). A 1,200-plane airborne assault preceded an amphibious assault involving more than 5,000 vessels. Nearly 160,000 troops crossed the English Channel on 6 June, and more than two million Allied troops were in France by the end of August.

The decision to undertake a cross-channel invasion in 1944 was taken at the Trident Conference in Washington in May 1943. General Dwight D. Eisenhower was appointed commander of Supreme Headquarters Allied Expeditionary Force (SHAEF), and General Bernard Montgomery was named as commander of the 21st Army Group, which comprised all the land forces involved in the invasion. The coast of Normandy of northwestern France was chosen as the site of the invasion, with the Americans assigned to land at sectors codenamed Utah and Omaha, the British at Sword and Gold, and the Canadians at Juno. To meet the conditions expected on the Normandy beachhead, special technology was developed, including two artificial ports called Mulberry harbors and an array of specialized tanks nicknamed Hobart's Funnies. In the months leading up to the invasion, the Allies conducted a substantial military deception, Operation Bodyguard, using both electronic and visual misinformation. This misled the Germans as to the date and location of the main Allied landings. Führer Adolf Hitler placed German Field Marshal Erwin Rommel in charge of developing fortifications all along Hitler's proclaimed Atlantic Wall in anticipation of an invasion.

The Allies failed to accomplish their objectives for the first day, but gained a tenuous foothold that they gradually expanded when they captured the port at Cherbourg on 26 June and the city of Caen on 21 July. A failed counterattack by German forces on 8 August left 50,000 soldiers of the 7th Army trapped in the Falaise pocket. The Allies launched a second invasion from the Mediterranean Sea of southern France (code-named Operation Dragoon) on 15 August, and the Liberation of Paris followed on 25 August. German forces retreated east across the Seine on 30 August 1944, marking the close of Operation Overlord.

Invasion stripes were alternating black and white bands painted on the fuselages and wings of Allied aircraft during World War II to reduce the chance that they would be attacked by friendly forces during and after the Normandy Landings. Three white and two black bands were wrapped around the rear of a fuselage just in front of the empennage (tail) and from front to back around the upper and lower wing surfaces.

After a study concluded that the thousands of aircraft involved in the invasion would saturate and break down the IFF system, the marking scheme was approved on May 17, 1944, by Air Chief Marshal Sir Trafford Leigh-Mallory, commanding the Allied Expeditionary Air Force. A small-scale test exercise was flown over the OVERLORD invasion fleet on June 1, to familiarize the ships' crews with the markings, but for security reasons, orders to paint the stripes were not issued to the troop carrier units until June 3 and to the fighter and bomber units until June 4.

Stripes were applied to fighters, photo-reconnaissance aircraft, troop carriers, twin-engined medium and light bombers, and some special duty aircraft, but were not painted on four-engined heavy bombers of the U.S. Eighth Air Force or RAF Bomber Command, as there was little chance of mistaken identity — few such bombers existed in the Luftwaffe and were already quite familiar to the Allies. The order affected all aircraft of the Allied Expeditionary Air Force, the Air Defense of Great Britain, gliders, and support aircraft such as Coastal Command air-sea rescue aircraft whose duties might entail their overflying Allied anti-aircraft defenses.

One month after D-Day, the stripes were ordered removed from planes' upper surfaces to make them more difficult to spot on the ground at forward bases in France. They were completely removed by the end of 1944 after achieving total air supremacy over France.

The stripes were five alternating black and white stripes. On single-engine aircraft each stripe was to be 18 inches (46 cm) wide, placed 6 inches (15 cm) inboard of the roundels on the wings and 18 inches (46 cm) forward of the leading edge of the tailplane on the fuselage. National markings and serial number were not to be obliterated. On twin-engine aircraft the stripes were 24 inches (61 cm) wide, placed 24 inches (61 cm) outboard of the engine nacelles on the wings, and 18 inches (46 cm) forward of the leading edge of the tailplane around the fuselage. American aircraft using the invasion stripes very commonly had some part of the added "bar" section of their post-1942 roundels overlapping the invasion strips on the wings, however.

In most cases the stripes were painted on by the ground crews; with only a few hours' notice, few of the stripes were "masked". As a result, depending on the abilities of the "erks" (RAF nickname for ground crew), the stripes were often far from neat and tidy.

Plans for the invasion of Normandy went through several preliminary phases throughout 1943, during which the Combined Chiefs of Staff (CCS) allocated 13½ U.S. troop carrier groups to an undefined airborne assault. The actual size, objectives, and details of the plan were not drawn up until after General Dwight D. Eisenhower became Supreme Allied Commander in January 1944. In mid-February Eisenhower received word from Headquarters U.S. Army Air Forces that the TO&E of the C-47 Skytraingroups would be increased from 52 to 64 aircraft (plus nine spares) by April 1 to meet his requirements. At the same time the commander of the U.S. First Army, Lieutenant General Omar Bradley, won approval of a plan to land two airborne divisions on the Cotentin Peninsula, one to seize the beach causeways and block the eastern half at Carentan from German reinforcements, the other to block the western corridor at La Haye-du-Puits in a second lift. The exposed and perilous nature of the La Haye de Puits mission was assigned to the veteran 82nd Airborne Division ("The All-Americans"), commanded by Major General Matthew Ridgway, while the causeway mission was given to the untested 101st Airborne Division ("The Screaming Eagles"), which received a new commander in March, Brigadier General Maxwell D. Taylor, formerly the commander of the 82nd Airborne Division Artillery who had also been temporary assistant division commander (ADC) of the 82nd Airborne Division, replacing Major General William C. Lee, who suffered a heart attack and returned to the United States.

Bradley insisted that 75 per cent of the airborne assault be delivered by gliders for concentration of forces. Because it would be unsupported by naval and corps artillery, Ridgway, commanding the 82nd Airborne Division, also wanted a glider assault to deliver his organic artillery. The use of gliders was planned until April 18, when tests under realistic conditions resulted in excessive accidents and destruction of many gliders. On April 28 the plan was changed; the entire assault force would be inserted by parachute drop at night in one lift, with gliders providing reinforcement during the day.

Jun 3, 2019

Angel Smith started out in the Marines as an enlisted aviation radio repairman and then separated to go to college. Once out, she encountered a Marine recruiter who was trying to sign up women pilots, so she took the flight test and was hooked.

After she received her undergraduate degree (she now has a masters degree and is now finishing up her doctorate) she attended Marine Officer School, then went to pilot training at Pensacola for her first flight at the controls of an airplane.

She went through flight school as a single parent of two young children, and got her first choice of aircraft - the C-130 Hercules. In the C-130, she was stationed at Futenma Air Station in Okinawa. One of her first missions was refueling Navy fighters.

After the flying assignment, Angel served as the aide to three different generals in three years. She became the speechwriter for the Commandant of the Marine Corps.

After that, she returned to flying in the C-130 at Miramar. Angel served for a total of 23 years.

May 30, 2019

The basic needs of the learner must be satisfied before he or
she is ready or capable of learning (see Chapter 1, Human
Behavior). The instructor can do little to motivate the learner
if these needs have not been met. This means the learner must
want to learn the task being presented and must possess the
requisite knowledge and skill. In SBT, the instructor attempts
to make the task as meaningful as possible and to keep it
within the learner’s capabilities.
Students best acquire new knowledge when they see a clear
reason for doing so, often show a strong interest in learning
what they believe they need to know next, and tend to set
aside things for which they see no immediate need. For
example, beginning flight students commonly ignore the
flight instructor’s suggestion to use the trim control. These
students believe the control yoke is an adequate way to
manipulate the aircraft’s control surfaces. Later in training,
when they must divert their attention away from the controls
to other tasks, they realize the importance of trim.
Instructors can take two steps to keep their students in a state
of readiness to learn. First, instructors should communicate a
clear set of learning objectives to the student and relate each new topic to those objectives. Second, instructors should
introduce topics in a logical order and leave students with a
need to learn the next topic. The development and use of a
well-designed curriculum accomplish this goal.
Readiness to learn also involves what is called the “teachable
moment” or a moment of educational opportunity when a
person is particularly responsive to being taught something.
One of the most important skills to develop as an instructor
is the ability to recognize and capitalize on “teachable
moments” in aviation training. An instructor can find or
create teachable moments in flight training activity: pattern
work, air work in the local practice area, cross-country, flight
review, or instrument proficiency check.
Teachable moments present opportunities to convey
information in a way that is relevant, effective, and memorable
to the student. They occur when a learner can clearly see how
specific information or skills can be used in the real world.
For example, while on final approach several deer cross the
runway. Bill capitalizes on this teachable moment to stress the
importance of always being ready to perform a go-around.

All learning involves the formation of connections and
connections are strengthened or weakened according to
the law of effect. Responses to a situation that are followed
by satisfaction are strengthened; responses followed by
discomfort are weakened, either strengthening or weakening
the connection of learning. Thus, learning is strengthened
when accompanied by a pleasant or satisfying feeling, and
weakened when associated with an unpleasant feeling.
Experiences that produce feelings of defeat, frustration,
anger, confusion, or futility are unpleasant for the student.
For example, if Bill teaches landings to Beverly during the
first flight, she is likely to feel inferior and be frustrated,
which weakens the learning connection.
The learner needs to have success in order to have more
success in the future. It is important for the instructor to create
situations designed to promote success. Positive training
experiences are more apt to lead to success and motivate the
learner, while negative training experiences might stimulate
forgetfulness or avoidance. When presented correctly, SBT
provides immediate positive experiences in terms of real
world applications.
To keep learning pleasant and to maintain student motivation,
an instructor should make positive comments about the
student’s progress before discussing areas that need
improving. Flight instructors have an opportunity to do this
during the flight debriefing. For example, Bill praises Beverly on her aircraft control during all phases of flight, but offers
constructive comments on how to better maintain the runway
centerline during landings.

Connections are strengthened with practice and weakened
when practice is discontinued, which reflects the adage “use
it or lose it.” The learner needs to practice what has been
learned in order to understand and remember the learning.
Practice strengthens the learning connection; disuse weakens
it. Exercise is most meaningful and effective when a skill is
learned within the context of a real world application.
Primacy, the state of being first, often creates a strong, almost
unshakable impression and underlies the reason an instructor
must teach correctly the first time and the student must learn
correctly the first time. For example, a maintenance student
learns a faulty riveting technique. Now the instructor must
correct the bad habit and reteach the correct technique.
Relearning is more difficult than initial learning.
Also, if the task is learned in isolation, it is not initially
applied to the overall performance, or if it must be relearned,
the process can be confusing and time consuming. The
first experience should be positive, functional, and lay the
foundation for all that is to follow.
Immediate, exciting, or dramatic learning connected to
a real situation teaches a learner more than a routine or
boring experience. Real world applications (scenarios)
that integrate procedures and tasks the learner is capable
of learning make a vivid impression and he or she is least
likely to forget the experience. For example, using realistic
scenarios has been shown to be effective in the development
of proficiency in flight maneuvers, tasks, and single-pilot
resource management (SRM) skills.
The principle of recency states that things most recently
learned are best remembered. Conversely, the further a
learner is removed in time from a new fact or understanding,
the more difficult it is to remember. For example, it is easy for
a learner to recall a torque value used a few minutes earlier,
but it is more difficult or even impossible to remember an
unfamiliar one used a week earlier.

May 27, 2019

Memorial Day endures as a holiday which most businesses observe because it marks the unofficial beginning of summer. The Veterans of Foreign Wars (VFW) and Sons of Union Veterans of the Civil War (SUVCW) advocated returning to the original date, although the significance of the date is tenuous. The VFW stated in 2002:

In 2000, Congress passed the National Moment of Remembrance Act, asking people to stop and remember at 3:00 PM.

On Memorial Day, the flag of the United States is raised briskly to the top of the staff and then solemnly lowered to the half-staff position, where it remains only until noon. It is then raised to full-staff for the remainder of the day.

The National Memorial Day Concert takes place on the west lawn of the United States Capitol. The concert is broadcast on PBS and NPR. Music is performed, and respect is paid to the men and women who gave their lives for their country.

Across the United States, the central event is attending one of the thousands of parades held on Memorial Day in large and small cities. Most of these feature marching bands and an overall military theme with the Active Duty, Reserve, National Guard and Veteran service members participating along with military vehicles from various wars.

During World War II, more airmen died in combat than Marines.

Operation Tidal Wave was an air attack by bombers of the United States Army Air Forces (USAAF) based in Libya and Southern Italy on nine oil refineries around Ploiești, Romania on 1 August 1943, during World War II. It was a strategic bombing mission and part of the "oil campaign" to deny petroleum-based fuel to the Axis. The mission resulted in "no curtailment of overall product output."

This mission was one of the costliest for the USAAF in the European Theater, with 53 aircraft and 660 air crewmen lost. It was proportionally the most costly major Allied air raid of the war and its date was later referred to as "Black Sunday". Five Medals of Honor and 56 Distinguished Service Crosses along with numerous others awards were awarded to Operation Tidal Wave crew members.

Here is the story of John C. Waldron:

June 4, 1942. The 15 Douglas TBD-1 Devastators of VT-8 launched from Hornet's flight deck in search of the enemy. Before takeoff, LCDR Waldron had a dispute with the Hornet's Commander, Air Group, Stanhope C. Ring, and Hornet CO Marc Mitscher about where the Japanese carriers would be found. Despite having a contact report showing the Japanese southwest of Hornet, Mitscher and Ring ordered the flight to take a course due west, in the hopes of spotting a possible trailing group of carriers. Waldron argued for a course based on the contact report, but was overruled. Once in the air, Waldron attempted to take control of the Hornet strike group by radio. Failing that, he soon split his squadron off and led his unit directly to the Japanese carrier group. Waldron, leading the first carrier planes to approach the Japanese carriers (somewhat after 9:00AM local time, over an hour before the American dive bombers would arrive), was grimly aware of the lack of fighter protection, but true to his plan of attack committed Torpedo 8 to battle. Without fighter escort, underpowered, with limited defensive armament, and forced by the unreliability of their own torpedoes to fly low and slow directly at their targets, the Hornet torpedo planes received the undivided attention of the enemy's combat air patrol of Mitsubishi Zero fighters. All 15 planes were shot down. Of the 30 men who set out that morning, only one—Ensign George H. Gay, Jr., USNR—survived. Their sacrifice, however, had not been in vain. Torpedo 8 had forced the Japanese carriers to maneuver radically, delaying the launching of the planned strike against the American carriers. After further separate attacks by the remaining two torpedo squadrons over the next hour, Japanese fighter cover and air defense coordination had become focused on low-altitude defense. This left the Japanese carriers exposed to the late-arriving SBD Dauntless dive bombers from Yorktown and Enterprise, which attacked from high altitude. The dive bombers fatally damaged three of the four Japanese carriers, changing the course of the battle.

May 23, 2019

The document that specifies the requirements of a Flight Review is AC 61-98B. From 61-98B:

Under § 61.56(c) no person may act as PIC of an aircraft unless within the preceding 24 calendar-months that person has accomplished a satisfactory flight review in an aircraft for which that pilot is appropriately rated. An appropriately-rated instructor or other designated person must conduct the flight review. The purpose of the flight review is to provide for a regular evaluation of pilot skills and aeronautical

Pilots and CFIs should be aware that, under § 61.56(d), there is no requirement for pilots who have completed certain proficiency checks and ratings within the preceding 24 calendar-months to accomplish a separate flight review. These accomplishments include satisfactory completion of pilot proficiency checks conducted by the FAA, an approved pilot check airman, a Designated Pilot Examiner (DPE), or a U.S. Armed Force for a pilot certificate, rating, or operating privilege. However, the FAA recommends that pilots consider also accomplishing a review under some of the following circumstances. For example, a pilot with an Airplane Single-Engine Land (ASEL) rating may have recently obtained a glider rating, but may still wish to consider obtaining a flight review in a single-engine airplane if the appropriate 24-month period has nearly expired.

Review of Maneuvers and Procedures:
(1) The maneuvers and procedures covered during the review are those which, in the opinion of the CFI conducting the review, are necessary for the pilot to perform in order to demonstrate that he or she can safely exercise the privileges of his or her pilot certificate.
Accordingly, the CFI should evaluate the pilot’s skills and knowledge to the extent necessary to ensure that he or she can safely operate within regulatory requirements throughout a wide range of conditions. The CFI should always include abnormal and emergency procedures applicable to
the aircraft flown in the flight review.
(2) The CFI may wish to prepare a preliminary plan for the flight review based on an interview or other assessment of the pilot’s qualifications and skills. The CFI should outline a sequence of maneuvers to the pilot taking the review. For example, this may include a cross-country flight to another airport with maneuvers accomplished while en route. It could also include a period of simulated instrument flight time. The CFI should request that the pilot conduct whatever preflight preparation is necessary to complete the planned flight. This preparation should include all items required in part 91, § 91.103, such as checking weather, calculating required runway lengths, calculating Weight and Balance (W&B), completing a flight log, filing a flight plan, and conducting the preflight inspection.
(3) Before beginning the flight portion of the review, the CFI should discuss various operational areas with the pilot. This oral review should include, but not be limited to, areas such as aircraft systems, speeds, performance, meteorological and other hazards (e.g., windshear and wake turbulence), operations in controlled airspace, and abnormal and emergency procedures.
The emphasis during this discussion should be on practical knowledge of recommended procedures and regulatory requirements.
(4) Regardless of the pilot’s experience, the CFI may wish to review at least those maneuvers considered critical to safe flight, such as stalls, slow flight, and takeoffs and landings. Based on his or her in-flight assessment of the pilot’s skills, the CFI may wish to add other maneuvers from the PTS appropriate to the pilot’s grade of certificate. All reviews should include those areas within the PTS identified as “Special Emphasis.” Appendix 5 includes a list of suggested maneuvers. The FAA does not intend this list to be all-inclusive, nor does it limit a CFI’s discretion in selecting other appropriate maneuvers and procedures. To the greatest possible extent, the CFI should organize and sequence the selected maneuvers in a realistic
scenario appropriate to the kind of flying normally done by the pilot.
(5) The role of the CFI during the review is to provide an evaluation. However, the instructor is not limited to this role and may provide specific instruction to an airman on any areas the instructor notes as being weak. This additional instruction does not preclude the pilot’s successful completion of the review as long as the deficiencies are corrected. If the additional instruction does not correct the deficiencies, and/or it becomes apparent to the instructor that additional flights will be necessary, the CFI should discuss the situation with the pilot and proceed accordingly.

May 20, 2019

Gregory Poole is a former Coast Guard flight engineer, based in Southern California. When he was a teenager, he saw a poster of a military helicopter, and that was his inspiration to enlist.

His training was in North Carolina, learning avionics, electrical, mechanical and rescue. He cross-trained in numerous fields.

As an early flight engineer, he performed a rescue at the bottom of a cliff where a car had gone off the road, and he had to conduct the rescue with the rotor blades inches from the face of the cliff. His rescue helicopter was the HH-52, similar to the Sea King helicopter.

As flight engineer, he performed all preflight and post-flight inspections, with special attention to hydraulics. During actual missions, he operated the night spotlight and forward-looking infra-red (FLIR), which was essential in night rescue missions.

Greg also participated in law enforcement missions.

Greg is also an experienced martial artist instructor. He started in Philippines martial arts, then branched in to aikido, tae kwan do, hapkido, jeet kun do and salat. He has developed his own system, and now trains youngsters.

May 16, 2019

In May of last year I was accepted into the Writers Guild Foundation Veterans Writing Project. The program accepts 50 veterans each year (I was turned down the previous year) and holds a 3-day Retreat to launch the year's activities.

We were divided into groups of about 8 veterans and paired with working screen writing professionals to brainstorm our topics and refine our writing process. Then we were mentored throughout the year by more professional writers, with meetings twice each month. those of us who did not live in the Los Angeles area were able to participate via Facebook video and telephone conferences.

I based my script on my Hamfist novel series. I quickly discovered that a screenplay is totally different from a novel, and my script evolved dramatically, mostly due to the feedback of my mentor, Sabrina Almeida. With her help and guidance, my script went from not-ready-for-prime-time to pretty darned good.

And now the yearlong program, for me, is over, and I was invited to "pitch" my script to industry heavyweights. So, two days ago, I went to Los Angeles for the pitch-fest.

Here’s the pitch:

I'm Major George Nolly of the US Air Force

Author of the Hamfist Novel Series, with multiple Best-sellers that have been ranked #1 Fiction in the Vietnam War - History category with over 151,000 units downloaded and paperback sales on Amazon.

I teach Aviation at Metro State University, and I'm a Flight Instructor at United Airlines, where I flew for 26 years after active duty.

I have two masters, and a doctorate in Homeland Security, but before that, I was a cadet at the US Air Force Academy because I wanted to be a pilot, just like my father.

I did two tours in Vietnam with 198 combat missions flying an F-4 fighter jet, and let me tell you, there is nothing in this world that compares to being strapped to two J79 engines pushing 36,000 foot pounds of thrust at Mach 1 while a SAM is closing in on your ass.

It was everything I hoped for and more.

But before I got into my first dogfight, I had to get through my first combat tour.

After pilot training, I went over as a FAC, a Forward Air Controller, in an O-2, which was a tiny, twin-prop Cessna used to fly low to the ground, and spot high-value targets in enemy territory.

It was NOT what I signed up for.

  • And that's where we meet our hero, Hamilton "Hamfist" Hancock, a hotshot pilot with the need for speed, who sabotoges his chance at a fighter assignment by shining his ass on his final flight in pilot training.

He's sent to Vietnam in an O-2, one of the slowest planes in the service, where he meets SPEEDBRAKE, fellow pilot and mentor, who shows him what a FAC really does:

He loiters in the area long enough to direct fighters in for an air strike. The way you do this is at night is by GOING CHRISTMAS TREE, where we would turn on all our exterior lights and light up like a christmas tree to attract enemy ground fire, so that Charlie would reveal himself to our fighters for an air strike.

It's on a close call going Christmas Tree where our hero earns the call sign HAMFIST.


When the Base Commander offers winner's choice of aircraft for the pilot with the highest kill ratio, Hamfist sees a way into an F-4, that is, if he can beat his nemesis, Tank, the squadron Top Dog.

However, Hamfist's relentless pursuit leads him to fly fast and loose. When his flying puts others in jeopardy, he is deemed reckless, and sent on mandatory R&R.

While on R&R in Tokyo, he meets SAMANTHA - SAM, a recent Harvard Law Grad. Samantha has just signed up to join the Air Force as a JAG, and has a thing for fighter pilots. For the first time, Hamfist has dreams of something big in his life, other than flying fast.

That dream is interrupted when Hamfist gets word that his Mentor SPEEDBRAKE is shot down, and Hamfist must return to Vietnam to pack up Speedbrake's things for his family.

On his first mission back, distracted by how he left things with Sam, Hamfist gets shot down over the trail, and injured during his rescue.

After he's patched up, he persuades the doc to clear him to fly, even though the full extent of his injuries are not yet known.

The deadline arrives for the competition, and he has just enough time for one more sortie to secure his lead over TANK.

However, when as he enters the target area, he hears a distress call from a downed F-4. Hamfist forfeits his target to rescue the pilot.

Hamfist returns to base as a hero, however, he loses the competition to Tank, and along with that, his dreams of piloting an F-4.

A medical exam reveals that his injuries were more severe than previously thought, and he also loses his Air Force Flight Clearance.

Hamfist is overcome by the failure in his pursuit to follow in his father's footsteps.

Unable to turn to Sam, for fear that her affections will change, now that he will never be a fighter pilot, he severs his relationship with her while she is still in Officer Training.

Hamfist is given the option to leave the service at the end of his tour with an Honorable Discharge, or remain grounded for the rest of his career.

When word of his heroism reaches the private sector, however, Hamfist is offered a job as a civilian test pilot... in an F-4.

Assigned as the Interim Squadron Intel Officer until a replacement arrives, he witnesses the dedication of the men left behind on base while pilots flew their combat missions.

- The maintenance crews that perform 20 man-hours to every one hour he was in the air.

He sees how each person's contribution to the war effort is critical.

Hamfist understands that the War Effort comes before his personal desires, and extends his tour in Vietnam as a Ground officer.

That's when his replacement Intel Officer arrives on base, and Hamilton walks in to brief... Samantha, freshly graduated from Intel School.


May 13, 2019

Tom Cappelletti wanted to be a pilot ever since he was a child, but his first Air Force assignment was as an engineer. Yom spent three years at Wright-Patterson Air Force Base as a Test Program Manager before getting an assignment to Undergraduate Pilot Training in the Reserves.

After earning his wings, Tom flew the C-9 aeromedical evacuation aircraft, flying patients and their families to medical facilities all over the united States. He has landed virtually everywhere that has 5000 feet of concrete in the aeromedical evacuation role.

Tom participated in the commissioning of a painting of the C-9 to hang at Scott Air Force Base to commemorate the aircraft.

Tom became an airline pilot with a major carrier, and now flies the B737NG. His routes include Hawaii, Canada, and South America. Like every other pilot at his airline tom is ETOPS (Extended Twin Engine Operations) qualified.

Tom has an eclectic collection of aviation memorabilia, books and prints, and has had many of the items personally signed.

May 9, 2019

From NCBI:

Normalization of deviance is a term first coined by sociologist Diane Vaughan when reviewing the Challenger disaster. Vaughan noted that the root cause of the Challenger disaster was related to the repeated choice of NASA officials to fly the space shuttle despite a dangerous design flaw with the O-rings. Vaughan describes this phenomenon as occurring when people within an organization become so insensitive to deviant practice that it no longer feels wrong. Insensitivity occurs insidiously and sometimes over years because disaster does not happen until other critical factors line up. In clinical practice, failing to do time outs before procedures, shutting off alarms, and breaches of infection control are deviances from evidence-based practice. As in other industries, health care workers do not make these choices intending to set into motion a cascade toward disaster and harm. Deviation occurs because of barriers to using the correct process or drivers such as time, cost, and peer pressure. As in other industries, operators will often adamantly defend their actions as necessary and justified. Although many other high-risk industries have embraced the normalization of deviance concept, it is relatively new to health care. It is urgent that we explore the impact of this concept on patient harm. We can borrow this concept from other industries and also the steps these other high-risk organizations have found to prevent it.

May 6, 2019

From Air Line Pilots Association:

In September 2016, Capt. David Whitson (United) was diagnosed with acute myeloid leukemia, a condition in which white blood cells that manage the body’s immune system form abnormally. The then B-787 first officer was treated at the Texas Oncology–Baylor Charles A. Sammons Cancer Center in Dallas, Tex., where he spent an initial 30 days undergoing tests and chemotherapy.

“I had a mutation called FLT3 that put me at high risk for not reaching remission and also in a high-incidence category for relapse even if remission was achieved,” he recalled, adding, “My best shot was to have a bone marrow transplant, also called a stem cell transplant. Without it, I had a 5 percent chance of survival.”

Whitson was released from the hospital for a brief break. During this period, doctors conducted a bone marrow biopsy and discovered that the pilot’s cancer was in remission, a condition necessary to achieve before a bone marrow transplant could be conducted. Whitson and his doctors quickly found a donor.

“It was hard for me to wrap my head around the fact that a complete stranger would be willing to give me bone marrow stem cells and potentially save my life,” he acknowledged. Whitson endured additional rounds of chemotherapy and a full-body radiation scan to ensure his body was ready and on Dec. 21, 2016, received the transplant. Within several days, his new immune system was up and running.

Thirteen days after the transplant, Whitson was released from the hospital. He noted that prior to the transfusion of stem cells his blood type was B+, but today it’s O-. In addition, the DNA in his blood is different from that in his body.

Whitson encourages everyone to donate blood. “I needed more than a dozen blood and platelet transfusions during my treatments,” he said. The United pilot also urges those interested to join the national bone marrow registry at or “There’s a lack of diversity within the registry, and minorities are greatly needed,” he shared.

“Every day is a gift,” Whitson remarked, who credits ALPA’s Aeromedical Office for advising him and helping him jump through the necessary hoops to acquire his special issuance medical certificate and return to the cockpit. He also gave a nod to his medical benefits, noting, “I was on long-term disability for more than two years, and my medical insurance was excellent. Thank you, ALPA!”

May 2, 2019

From the Pilot’s Handbook of Aeronautical Knowledge:

The stability of the atmosphere depends on its ability to
resist vertical motion. A stable atmosphere makes vertical
movement difficult, and small vertical disturbances dampen
out and disappear. In an unstable atmosphere, small vertical air
movements tend to become larger, resulting in turbulent airflow
and convective activity. Instability can lead to significant
turbulence, extensive vertical clouds, and severe weather.
Rising air expands and cools due to the decrease in air
pressure as altitude increases. The opposite is true of
descending air; as atmospheric pressure increases, the
temperature of descending air increases as it is compressed.
Adiabatic heating and adiabatic cooling are terms used to
describe this temperature change.

The adiabatic process takes place in all upward and
downward moving air. When air rises into an area of lower
pressure, it expands to a larger volume. As the molecules
of air expand, the temperature of the air lowers. As a result,
when a parcel of air rises, pressure decreases, volume
increases, and temperature decreases. When air descends,
the opposite is true. The rate at which temperature decreases
with an increase in altitude is referred to as its lapse rate.
As air ascends through the atmosphere, the average rate of
temperature change is 2 °C (3.5 °F) per 1,000 feet.
Since water vapor is lighter than air, moisture decreases air
density, causing it to rise. Conversely, as moisture decreases,
air becomes denser and tends to sink. Since moist air cools
at a slower rate, it is generally less stable than dry air since
the moist air must rise higher before its temperature cools
to that of the surrounding air. The dry adiabatic lapse rate
(unsaturated air) is 3 °C (5.4 °F) per 1,000 feet. The moist
adiabatic lapse rate varies from 1.1 °C to 2.8 °C (2 °F to
5 °F) per 1,000 feet.
The combination of moisture and temperature determine the
stability of the air and the resulting weather. Cool, dry air
is very stable and resists vertical movement, which leads to
good and generally clear weather. The greatest instability
occurs when the air is moist and warm, as it is in the tropical
regions in the summer. Typically, thunderstorms appear on
a daily basis in these regions due to the instability of the
surrounding air.

As air rises and expands in the atmosphere, the temperature
decreases. There is an atmospheric anomaly that can occur;
however, that changes this typical pattern of atmospheric
behavior. When the temperature of the air rises with altitude, a
temperature inversion exists. Inversion layers are commonly
shallow layers of smooth, stable air close to the ground. The
temperature of the air increases with altitude to a certain
point, which is the top of the inversion. The air at the top
of the layer acts as a lid, keeping weather and pollutants
trapped below. If the relative humidity of the air is high, it
can contribute to the formation of clouds, fog, haze, or smoke
resulting in diminished visibility in the inversion layer.
Surface-based temperature inversions occur on clear, cool
nights when the air close to the ground is cooled by the
lowering temperature of the ground. The air within a few
hundred feet of the surface becomes cooler than the air above
it. Frontal inversions occur when warm air spreads over a
layer of cooler air, or cooler air is forced under a layer of
warmer air.

From AC 006B:

Vertical Motion Effects on an Unsaturated Air Parcel. As a bubble or parcel of air ascends (rises), it moves into an area of lower pressure (pressure decreases with height). As this occurs, the parcel expands. This requires energy, or work, which takes heat away from the parcel, so the air cools as it rises. This is called an adiabatic process. The term adiabatic means that no heat transfer occurs into, or out of, the parcel. Air has low thermal conductivity, so transfer of heat by conduction is negligibly small.

The rate at which the parcel cools as it is lifted is called the lapse rate. The lapse rate of a rising, unsaturated parcel (air with relative humidity less than 100 percent) is approximately 3 °C per 1,000 feet (9.8 °C per kilometer). This is called the dry adiabatic lapse rate. This means for each 1,000-foot increase in elevation, the parcel’s temperature decreases by 3 °C. Concurrently, the dewpoint decreases approximately 0.5 °C per 1,000 feet (1.8 °C per kilometer). The parcel’s temperature-dewpoint spread decreases, while its relative humidity increases. 

This process is reversible if the parcel remains unsaturated and, thus, does not lose any water vapor. A descending (subsiding) air parcel compresses as it moves into an area of higher pressure. The atmosphere surrounding the parcel does work on the parcel, and energy is added to the compressed parcel, which warms it. Thus, the temperature of a descending air parcel increases approximately 3 °C per 1,000 feet (9.8 °C per kilometer). Concurrently, the dewpoint increases approximately 0.5 °C per 1,000 feet (1.8 °C per kilometer). The parcel’s temperature-dewpoint spread increases, while its relative humidity decreases.

The parcel and the surrounding environmental air temperatures are then compared. If the lifted parcel is colder than the surrounding air, it will be denser (heavier) and sink back to its original level. In this case, the parcel is stable because it resists upward displacement. If the lifted parcel is the same temperature as the surrounding air, it will be the same density and remain at the same level. In this case, the parcel is neutrally stable. If the lifted parcel is warmer and, therefore, less dense (lighter) than the surrounding air, it will continue to rise on its own until it reaches the same temperature as its environment. This final case is an example of an unstable parcel. Greater temperature differences result in greater rates of vertical motion.

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