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Preflight Inspection – “Hurry up! It’s Cold!” - December 2007

Gene Benson

We have all heard the term, “fair weather pilot” used to describe those who only fly on nice days. There are also “fair weather preflighters.” Most pilots are very conscientious about performing the preflight inspection regardless of the environment. But, there are others who seem to think that the time allotted to the preflight inspection should be inversely proportional to the ambient temperature.  Perhaps it should be the other way around. The colder it is outside, the more attention should be paid to the preflight inspection.  There are plenty of things that can go wrong regardless of the weather. It can be argued that there are more things to go wrong when the temperature is below freezing than on a warm day.  Spending more than a few minutes outside on a windy, cold ramp isn’t pleasant. Spending a few hours in a cold field or forest while waiting to be rescued would be even more unpleasant.

Fuel contamination is one example.  The wildly varying temperatures of late fall and early winter are notorious for producing condensation inside partially filled fuel tanks. The condensation makes its way into the fuel and can cause serious power interruptions. The water collects, in theory, at the lowest point of the fuel tank where the sump is located. If the temperature is below freezing at the time of the preflight inspection, the water might be frozen and the sump might not function and fuel might not flow into the sample cup. Again, in theory, the water is frozen and won’t be drawn into the engine. There once was a theory that the Earth was flat. It didn’t work out very well. The theories about the water being frozen in the fuel tank will probably work out just as well.

There is only one safe way to deal with a frozen sump and it isn’t very popular. The entire airplane must be warmed enough so that the water melts and can be drained from the fuel system.  That means putting the airplane in a heated hangar for several hours. I have seen pilots leave a preheater hose near the fuel sump until it thaws. This method will melt the ice in the immediate vicinity of the sump but will not address the ice that is almost certainly present elsewhere in the tank.

Remember the theory that the water collects at the lowest point of the fuel system? That theory also works out as well as the one about the world being flat. That simply isn’t true. If there is water at the sump, there is water hiding elsewhere in the tank. I can prove it. If you don’t believe me, send me an email, (gene@genebenson.com) I’ll send you a waiver of liability to sign, return it to me, and I’ll send you instructions for a demonstration that you can conduct on your own airplane. 

The accident records contain numerous reports of accidents caused by water contamination.  Most reports state that the pilot sumped the fuel tanks before flight.  Some of those pilots probably fibbed about their thoroughness, but not all.  A friend of mine who I know to be meticulous about a preflight inspection, crashed his Cessna 180 a couple of years ago after the engine failed on takeoff.  Water was found in the fuel system after the accident.  He said he sumped the tanks and I believe him.  Taildraggers are particularly vulnerable to this problem. The water goes to the rear of the tank when the airplane is parked and then runs toward the fuel ports when in level attitude.

Once water has been found at the sump in any airplane, the wings should be rocked gently to encourage any remaining water to find its way to the sump.  This is a lengthy process of rock , wait, drain.  Repeat. Repeat. Repeat.

So what other items can be aggravated by cold weather? How about a frozen trim pulley? This is particularly a problem for single-engine Cessnas but can apply to any airplane. Here’s the scenario. A well-meaning technician, particularly one operating in the warmer climates, will lubricate the trim cable and pulleys with WD-40. This is a versatile substance and a good lubricant, but the ‘WD” stands for “water dispersant”. Water is absorbed and held by the lubricant. That’s great for controlling corrosion, but not so great when the temperature drops and the water will freeze, immobilizing the trim cable.  Exercising the trim system is always important, but becomes critical when contemplating flying an airplane that has spent time in a sub-freezing environment.

It is also critical to take the time and effort to remove any contamination from the flying surfaces.  All pilots know the danger associated with ice, snow, or frost covered flying surfaces. Some pilots still try to ignore the danger especially when the culprit is light frost. The accident records show many cases where airplanes ran off the end of runways trying to get airborne with a thin coating of frost on the wings.

The airplane’s electrical system also deserves a closer look when ambient temperatures are low.  Aircraft batteries are typically not as robust as those in our automobiles.  Conventional wisdom is that if you can get the airplane started the system will take care of itself.  That might be true for day VFR flights in the likes of a Cessna 172, but it doesn’t extend to airplanes that require electrical power to operate the landing gear, advanced avionics, or even the engine controls. A recent accident in Germany involved the Diamond DA42 Twin Star that uses a full authority digital engine control (FADEC).  The pilot took off with a weak battery that was rapidly depleted by the retraction of the landing gear.  As the battery ceased to provide power to the FADECs, both engines were automatically shut down.  Even without a FADEC, the loss of electrical power in an airplane with a glass cockpit could be very interesting even though claims of backup power are made.

There are many other items deserving of extra attention in cold weather.  Even some of the flight instruments might not function properly until the lubricant in the tiny bearings warms up.  A small crack in the exhaust system might bring carbon monoxide into the cabin through the heater or defroster.  The list goes on.

In summary, the preflight inspection is critical regardless of the weather, but cold weather provides more opportunity for problems to develop.  Finding a problem during a preflight inspection can spoil recreational or travel plans.  But, remember that it is always better to be on the ground wishing that you were flying than to be flying and wishing that you were on the ground!

 

Avoiding Ice (and Dealing With It When You Can’t) - Nov. 2007

Gene Benson

Last fall brought with it a huge controversy about the legality of flying in conditions that might produce structural ice if the airplane was not certified for flight into known ice. A flight instructor demanded that the FAA define flight into known icing conditions. Beware the old saying, “Be careful what you wish for because you might get it.” A letter of interpretation written by a lawyer employed by the FAA took the official position to the ridiculous. It effectively made it a violation of FARs to fly in the northeast from November through April. It was later rescinded.

The fact is that we don’t want the government to tell us precisely when it’s illegal to fly because of possible icing. When backed into a corner, any government agency will have no choice but to take the most conservative position possible. It is much better if we can decide for ourselves what is an acceptable risk. Any flight poses some risk. Flying when there is a possibility of having ice form on the airplane structure increases that risk. As pilots, we must make smart decisions about when to fly and when to stay on the ground. When the decision is made to fly, we must make smart decisions about managing the risks as the flight progresses. That includes managing an inadvertent encounter with structural icing.

The formation of structural ice on the airplane is supposed to be primarily an IFR problem. That’s true most of the time. But, there are a few times when it can be encountered in VFR conditions. In any case, structural ice is bad news unless the airplane is equipped to handle it and is certified for flight into known icing conditions. Most general aviation airplanes are not certified even though they may have some deice equipment. Even airplanes that are supposedly able to deal with ice sometimes still have a problem in severe icing conditions.

The ice can disrupt the smooth airflow over the flying surfaces, change the shape of the propeller(s) causing a loss of thrust, block engine intake air resulting in partial or complete power loss, block pitot and static sources causing erroneous instrument indications, block the pilot’s view out the windshield, and even lead to the structural failure of external antennae.

Structural ice needs to have two conditions present to form: visible moisture and ambient temperature near or below freezing. Ice can form when the outside air temperature (OAT) gage reads a few degrees above freezing because of the expansion and therefore cooling effect of airflow. The most obvious icing conditions exist when flying in the clouds when the temperature is below freezing. A less obvious situation is encountered when flying in freezing drizzle or freezing rain below an overcast and with relatively good visibility. Freezing rain is generally considered to be the most hazardous form of structural icing.

There are technically three kinds of ice that form on airplanes. They are clear, rime, and mixed. The distinction between the three matters little when it is forming on an airplane not equipped to handle structural ice.

The only way to positively avoid structural icing is to leave the airplane in the hangar on any day that does not boast clear skies or temperatures above freezing at the proposed flight altitude. Since that is neither practical nor desirable in the northeastern part of the U.S., some guidelines must be established. Each pilot must establish his or her own set of guidelines that realistically reflect the capabilities of the airplane and the experience and comfort levels of the pilot.

I have logged several thousand hours flying through the ice-laden skies of the northeast. My philosophy used to be that it wasn’t “known icing” if it wasn’t on my wings. I have a good understanding of structural icing and I was always able to deal with inadvertent icing encounters effectively by a small change in altitude or routing. In May of 2000 I experienced a severe icing encounter that made me realize that what I had perceived as superior skill had included a lot of superior luck. The story of that icing encounter appears in the “Pilot Stories” section of this site.

So what about personal icing guidelines? Each pilot will have to develop his or her own, but here are mine as they stand at this time with respect to airplanes not certified for flight into known icing conditions:

1. I will not depart with any ice, snow, or frost on any part of the airplane.
2. Not withstanding the standard warning of possible icing in clouds and in precipitation above the freezing level, I will not proceed on any leg for which there is forecast or reported structural icing within 2000 feet of my intended altitude.
3. I will not enter clouds that are categorized as broken or overcast above the freezing level when the ceiling is less than 3000 feet.
4. I will not fly below a temperature inversion when the temperature at my intended altitude is below 40 degrees F.
5. If I inadvertently encounter a trace to light ice while airborne, I will take immediate action, usually a climb, to stop the accumulation. If the trace to light ice continues to accumulate after an altitude change of 2000 feet I will take decisive action, usually a 180 degree turn, to get out of the ice.
6. If I inadvertently encounter moderate or greater ice while airborne, I will take decisive action, usually a 180 degree turn, to get out of the ice.

These are my personal guidelines and are presented only as an example. Other pilots may choose other criteria or solutions.

In summary, ice belongs in the cooler and not on the airplane. Pushing the envelope with respect to structural icing is, as I learned the hard way, simply isn’t good airmanship. Always remember, “Fly like your life depends on it.”

 

Go-Arounds – Knowing When is as Important as Knowing How - October 2007

Gene Benson

Most pilots are taught that executing a go-around is the prudent course of action if the landing is not progressing normally and a safe outcome is not assured. That is a good practice but it isn’t always that simple. The pilot must be proficient in executing the go-around properly in the particular airplane being flown and must make the decision to execute the go around in a timely manner.

Much could be written about the execution of the go-around but I will only summarize here.  I will limit the discussion to single-engine airplanes, noting that much of the same applies to light, multiengine airplanes providing that both engines are operating. Most light, multiengine airplanes are marginal or incapable of a successful go-around with an engine inoperative.

The conventional wisdom in general aviation airplanes is to perform “power, pitch, flaps, gear” in that order. In other words, add full power, pitch for the climb, retract the flaps (at least partially), and then raise the landing gear. That sequence worked just fine in the low-powered, high-drag Cessna’s and Pipers of the 1970s but the first two items need to be revisited for the new generation of airplanes introduced in the last ten years. The higher horsepower and lower drag designs make it more desirable to achieve at least a level attitude, if not a slightly nose-high attitude, before the application of power.

The sequence of at least partially retracting flaps before raising the landing gear continues to be correct. Extended flaps produce more drag than extended landing gear. Also, the landing gear usually produces more drag when in transit than when extended. Of course, the airspeed must be sufficient to maintain flight at the lesser flap setting before the flaps are raised. If an airplane has a stalling speed of 52 knots with full flaps extended and 61 knots with flaps retracted, it would unwise to retract the flaps when flying at 58 knots.

So the general technique for initiating a go-around should be

1. Pitch to the level flight attitude.
2. Smoothly add full power, first advancing the propeller control to the high RPM position if the airplane has a constant speed propeller.
3. Pitch to the proper climb attitude as airspeed permits.
4. Retract flaps as airspeed permits.
5. Retract landing gear.

Of course, the airplane should be trimmed as necessary so to avoid excessive control pressure.

It must be noted that this is a general technique. Many manufacturers, especially the makers of the new generation of airplanes, are very specific about the go-around procedure to be used. It is critical for each pilot to study the POH before a flight in an unfamiliar airplane and to commit any special procedures to memory before the flight. After all, when the deer runs onto the runway as the airplane is on short final is probably not the best time to be looking up the recommended go-around procedure.

The go-around procedure must be practiced in addition to being memorized. A checkout in an unfamiliar airplane always includes seeing how it handles in a stall. Knowing how it handles in a go-around is just as important.

Like everything else in aviation, it isn’t enough to just practice the go-around technique during a checkout. It must be part of a recurrent training program so that it will be second nature when it is needed. A Cirrus SR-22 was destroyed and the pilot was fatally injured in Maryland in 2006. The pilot correctly decided to execute a go-around during a landing attempt but his failure to follow the manufacturer’s procedure to retract the flaps to 50% for go-around resulted in a stall/spin accident. This probably would have been prevented had the pilot been involved in a recurrent training program.

Knowing how to execute the go-around maneuver and being proficient at it are extremely important but still more is required. The pilot must possess the skill and knowledge to decide when to execute a go-around. Many accidents have happened because the pilot waited too long before deciding to abort the landing and the laws of physics prevailed.

Terrain, runway length and condition, wind, airplane maneuverability, and other factors all affect the go-around decision. A general rule is that the airplane should be landed in the first third of the runway and if that isn’t going to happen a go-around should be executed. But what about the runway that is barely long enough for the airplane, or slopes downhill, or requires a landing with a tailwind due to terrain, or is covered with packed snow? Maybe the first tenth of the runway must be the touchdown zone under certain conditions. (Maybe if landing on the first third of the runway isn’t sufficient an alternate airport or runway should be considered.)

If the terrain ahead is flat and there are no obstructions, perhaps the pilot can wait and make the decision to go around as the airplane floats past the first third of the runway. If the terrain rises rapidly ahead, the decision to abort the landing must be made early enough so that the airplane can climb safely.

In 2004, a Cessna 150 crashed in Virginia while attempting a go-around. The pilot was seriously injured and the airplane was destroyed. The crash occurred as the result of a stall while the pilot was attempting to climb over rising terrain off the departure end of the runway. The airplane was simply unable to climb more rapidly than the terrain was rising. Executing the go-around at a higher altitude could have prevented the accident. The possibility of a go-around must always be considered when planning an approach. This pilot allowed himself to get into a situation where he had no viable options once he descended for the landing.

In summary, pilots should always be prepared to execute a go-around if necessary. A safe go-around requires knowledge of how it should be executed in the specific airplane type, proficiency in performing the execution, and the judgment to decide when the go-around maneuver is prudent.

 

Recurrent Training for GA – It doesn’t have to be unpleasant! - September 2007

Gene Benson

Things we should do regularly but often don’t: review life insurance coverage, exercise, change the oil in the lawnmower, clean the lint out of the dryer exhaust, attend local government meetings, participate in a recurrent pilot training program. How do you plead to multiple counts of misdemeanor procrastination? If you plead guilty to this charge you are certainly in the vast majority of pilots. We each have our own mental list of things we should do but that we put off. In the case of this writer, I put off having a colonoscopy for five years. Finally, I succumbed to the badgering of my friend and DME to have it done. The mostly painless procedure detected a malignant lesion. Major surgery was required to “resection” my colon. It was caught early and two months later I was back to full throttle. But, if I had gone for the colonoscopy five years earlier, it most likely would have been just a polyp that was simply snipped off during the colonoscopy. If I had procrastinated another year, the cancer would probably have spread and been incurable.

The point to make is that procrastination can kill us. Failure to change the oil in the lawnmower is probably not fatal. A dryer fire just might be. Not detecting colon cancer early most certainly is.

So why do human beings, supposedly the most intelligent of all the creatures on the Earth, put off doing things that should be done? The answer is very simple. Given the limited time that we all have, we chose to do the things that are first, absolutely necessary to maintain our status quo. These things include paying bills, taking out the garbage, and the like. Second, with the remaining time that we have, we chose to do things that are enjoyable and avoid doing things that are unpleasant or mundane. I don’t have any suggestions on how to make reviewing life insurance coverage or cleaning the lint out of the dryer enjoyable, but I can address another item that can be a life-saver. That is a recurrent pilot training program.

The airlines have a safety record that is 97 times better than that of general aviation. Even though the airlines enjoy the advantages of better equipment, dedicated meteorologists and dispatchers, larger airports, and two pilot operations, we can’t explain away the huge disparity in the safety records.

One big difference between airline and general aviation operations is in the requirements to keep pilots proficient. Airline pilots typically have a training event at least every six months. At least annually, they put their pride and possibly employment on the line to take a rigorous simulator check ride. General aviation pilots, by contrast, can get away with a flight review every other year that may consist of only one hour of flight instruction and one hour of ground instruction. Pilots flying higher performance airplanes are often required by their insurance companies to complete a factory training course, but the average pilot flying the Cessna 172 is largely on his or her own to maintain proficiency. Since proficiency training can be costly and it’s not very much fun to get beat up by some kid with a fresh CFI, it frequently falls into the “things procrastinated” column.

To quote the infomercial hawkers, “But wait, this is revolutionary!”  What if a solid recurrent training program was cost effective and fun? It can be. A little thought and a little networking can help create a program that works and will be followed through. Any pilot can create such a program. Here are some key elements.

Relevance – If the program is not perceived as relevant, it won’t be followed. Practicing locating position by VOR cross bearings is not relevant for the pilot who routinely flies with dual panel-mounted GPS units plus a handheld unit as a backup. Challenging that pilot to quickly and efficiently navigate the menus of those GPS units is very relevant.

Cost effectiveness – The cost of avgas and all the other expenses associated with tooling around the airspace is substantial. Without the benefit of the full-motion simulators available to the airlines, it is impossible to maintain proficiency without actually flying the airplane. The key is to maximize proficiency training opportunities during routine flying and to have a structured plan for accomplishing objectives not possible to cover during a pilot’s usual operations. Some of these items can be effectively undertaken in a PCATD. These units are terrific for practicing procedures that don’t involve actual stick and rudder skills. Even the readily available flight simulator programs can be valuable in accomplishing some of the training objectives. The time can’t be logged, but the point of a recurrent program is to maintain proficiency, not fatten the logbook.

Enjoyable – Many people get together with friends to complete their exercise programs. Some of these people would not go to the gym or the walking path without the support and camaraderie of people sharing similar goals and interests. There is no valid reason why a recurrent pilot training program can’t work the same way. It isn’t necessary to have a CFI present at all times. A pair or small group of pilots can accomplish a great deal when working together.

Here are some suggested steps in setting up a workable recurrent training program that is likely to be followed.

First, if you’re not already registered, visit www.faasafety.gov and register for the new safety program. The program is dramatically different from the old program in several ways, most of which are for the better. The new program allows the pilot customize the flight training portion to suit the kind of flying that he or she actually does. Three hours of flight instruction are no longer required if proficiency can be demonstrated in less time. Of course, proficiency is the key. A problem that this writer had with the previous program was that three hours of dual instruction were required but there was no requirement to demonstrate proficiency. Ground or academic training can also be customized by selecting from on-line courses or live seminars. Even though the program is improved, it is still not sufficient to be called a recurrent training program. It keeps the pilot legal, but far too many legal pilots die in aircraft accidents.

Second, make a thorough, honest appraisal of the kind of flying that you do and that you might do. The instrument rated pilot who does a great deal of cross country flying in the Northeast would be well-served to incorporate lots of “what-if” instrument scenarios into a training program. But beware the trap. The pilot who says, “I never fly at night,” and does not include any night proficiency work must have firm resolve to never fly at night. Sometimes it becomes very inconvenient to stay overnight and the temptation to complete the flight with the last 90 minutes in the dark is overwhelming. If there is even a remote possibility of encountering night conditions, the program must include these operations.

Third, write down your objectives for the program and how each objective will be met. Include the equipment that will be required and make sure that you have access to it. For example, a PCATD can be very useful, but don’t list it if there is not one available. (Consider having each member of the group chipping in on the purchase of one, something like a flying club owns an airplane. They can be had for less than $5000 and can save that amount in avgas and maintenance costs very quickly. Maybe it can be leased to the local FBO and it can actually become a profit center.)

Finally, seek an existing group or form your own group of fellow pilots who are willing to work together on proficiency training. Everyone in the group need not be at the same certificate or rating level. Diversity can enhance the experience. Set up a regular training schedule and stick to it. Not everyone will attend each session and that’s fine. Take turns leading brief discussions of academic topics. Rotate the duty of searching the NTSB’s accident database and selecting three accidents per month for discussion. Choose accidents that have something in common with the group’s flying activities. Take turns flying as safety pilot for each other, even when a safety pilot is not required. Use routine, necessary flights that would be conducted anyway as training opportunities whenever possible. Upgrade the title to evaluation pilot and have a critique prepared. It’s very helpful to see your own flying through the eyes of your peers. Both the evaluator and pilot being evaluated must approach the critique as a positive learning experience. Low time pilots should also be allowed to serve as evaluators. Sometimes a pilot fresh out of a training program can add some valuable insight. If a PCATD is available, use it as much as possible. Pilots can take turns flying various scenarios and the rest of the group can critique the performance.

Skill and knowledge will increase rapidly once a structured recurrent training program is begun. There can be a huge difference between being legal and being really safe.  Besides, what is safe enough? No matter how skilled and knowledgeable the pilot, there is always room for improvement. If that weren’t so, the airlines wouldn’t spend the tens of thousands of dollars it costs to provide a recurrent training programs to a 20,000 hour airline captain.

If you need help deciding what to include in your recurrent training program or how to structure it, contact me at gene@genebenson.com and I’ll help. It’s a free service that I perform as part of my duties as a volunteer FAAST Team Lead Representative.

To Err is Human…And Not Necessarily Fatal - August 2007

Gene Benson

A few days ago I was watching a television debate involving a group of politicians who would all like to be President of the United States. I was awed by how none of these individuals has apparently ever made a mistake in the past nor is capable of making a mistake in the future. It’s just too bad that we mortal pilots aren’t as infallible.

As human beings we all make mistakes. If anyone doubts that, a query to a spouse or significant other will most likely set the record straight. I have made lots of errors while flying airplanes. Every pilot that I know has made errors while flying airplanes. It would be very nice if we were all as perfect as the politicians I was watching on TV but clearly we are not. The question quickly becomes how to manage the errors that we make.

Error management, whether related to aviation or any other activity which has inherent risks, involves avoiding the error whenever possible, trapping an error if it occurs, and then mitigating the effect of the error. The basis of this error management approach is that most errors do not singly lead to an accident. Most accidents are a result of a series of errors, often compounding themselves. This is called the “Error Chain”. The goal of error management is to break the error chain before the accident happens. Here’s how it works.

First, though it is inevitable that we will make errors, we would like to avoid as many of them as possible. This is best accomplished by being as thorough as possible in maintaining our proficiency, making sure that the airplanes we fly are well maintained, doing our preflight planning, and adhering to accepted safety practices. If we can avoid the error, the chain never gets started and there is no need to take additional action. Avoiding errors greatly reduces the pilot’s workload, reduces stress, and makes flying generally more enjoyable.

But regardless of how well trained and conscientious the pilot may be, the occasional error will occur. The VFR pilot may decide to takeoff into marginal weather that is incorrectly forecast to improve. The presence of a bird’s nest resting on an exhaust pipe in a well-hidden area inside a cowling might go undetected during the preflight inspection. A minor distraction might cause an instrument pilot to descent slightly below the minimum descent altitude (MDA) while on an instrument approach.

Once the error has been allowed to occur, it must not be allowed to compound itself and create other errors. For example, the pilot who took off into marginal weather must recognize that the conditions are not improving. Recognizing that an error has occurred and that corrective action is necessary is called trapping the error. If the pilot continues the flight into adverse weather, the initial error of taking off might lead to the temptation to scud run of fly in instrument conditions without adequate training. Either of these additional errors could lead to still more errors, or links in the error chain, such as straying into a thunderstorm of encountering structural icing conditions. These complications could lead to a final link in the error chain such as loss of control in a thunderstorm or a controlled flight into terrain (CFIT) accident if unable to maintain a safe altitude due to structural ice.

The final step in breaking the error chain is to take corrective action against the initial error. This is called mitigating the error. In our example, once the pilot recognizes that departing into the existing weather was a mistake, he or she must decide on appropriate corrective action, or mitigation. In this case, diverting to an alternate airport or returning to the departure airport might mitigate the error.

Our earlier example of allowing a bird’s nest to go undetected on the preflight inspection, is a true story that actually happened to this writer. The story, “I don’t Think This Airplane Should be Leaving a Vapor Trail” appears elsewhere on this site. Potential tragedy was avoided by breaking the error chain. The error was in not detecting the presence of the bird’s nest prior to engine start. It would have been much better and much less costly had I avoided the error. Since I did not avoid the error, I trapped the error by recognizing that the small amount of white smoke coming from the left engine nacelle was not normal. I mitigated the error by shutting down, evacuating the airplane, and extinguishing the fire.

Regarding the example where the instrument pilot might descend below the minimum descent altitude, the error should be avoided by maintaining instrument proficiency, completing an approach checklist, and other measures of due diligence. Nevertheless, it is not an uncommon error. If the error is not avoided, it must be trapped by quickly recognizing that the error has occurred. This is two-part exercise in that the pilot must know what the MDA is and also recognize that the airplane has descended below it. Mitigation is accomplished by smoothly initiating a climb back to the MDA if the deviation is minor (less than 80 feet), or executing the missed approach procedure for a greater deviation.

So in summary, even us error-prone mortals can safely fly airplanes. A single error rarely results directly in an accident. Errors that go undetected or that are followed by a compounding error may form an error chain. This chain of mistakes or bad judgments can easily lead to an accident. All pilots have a duty to themselves, their passengers, their families, and the folks on the ground below to avoid as many errors as possible. It is simply not possible to avoid all errors so steps must be taken to trap the error and then mitigate its effects.

 

Underlying Causes – The Third Domain - July 2007

Gene Benson

While it’s true that airplanes often crash because pilots didn’t heed the warnings listed in the first paragraph of the introduction above, the real question is why the warnings weren’t heeded. I’ll bet you’ve never heard a pilot say, “I don’t do fuel calculations, that’s only for sissies.” Or, “I never bother doing a preflight inspection, I know everything is fine with my airplane.” We pilots talk a good game, but we don’t always make good on our word.

Fuel starvation accidents make the perfect example. Every student pilot is taught the following:

1. Never trust the fuel gages; always check the tanks visually.
2. Calculate the fuel needed for the flight and keep a reserve of at least 30 minutes in the daytime and 45 minutes at night.
3. For cross-country flights, keep a running flight log as the trip progresses so that changes in ground speed, and therefore estimated time enroute and fuel consumption, can be tracked.
4. For local flights, know how much fuel is onboard in minutes, note the takeoff time, and calculate the time at which the flight must terminate, allowing for adequate reserve fuel.

But fuel starvation accidents continue to happen. For example, take the case of the Cessna 150 in Massachusetts. The pilot pulled his airplane out of the hangar, did a run-up, and took off. At about 700 feet of altitude, the engine suddenly lost power but the prop continued to windmill. He instinctively lowered the nose, planning to land straight ahead when the engine suddenly roared back to life. Breathing a sigh of relief, he flew around the pattern and landed safely. He taxied back to his hangar and did another run-up to see if he could detect the problem. Just like the first time, the run-up was fine. He decided that the power loss must have been some sort of gremlin so he took off again. He learned a hard lesson that cause and effect are more realistic problem producers than are gremlins. At only about 500 feet this time the engine lost power again. Without sufficient time or altitude, he landed straight ahead into some small trees. He received only a few cuts and bruises, but the airplane went to the salvage yard. Examination of the wreckage found that the fuel tanks were not compromised and held only a couple of pints of fuel. He had done a run-up, but had apparently not done a preflight inspection. He most certainly did not visually check the fuel quantity. As the airplane assumed the climb attitude, the small amount of fuel available ran toward the rear of the tanks and away from the fuel ports. Lowering the nose after the first power loss allowed the fuel to flow back over the fuel ports and into the carburetor resulting in restoration of power. The run-up after the first trip around the pattern was normal because the level attitude of the airplane allowed sufficient fuel to flow over the fuel ports. The second takeoff again caused the fuel to unport and there simply wasn’t enough fuel left to allow for the power to be restored by leveling the airplane.
 
So let’s see a show of hands for how many people believe that this pilot would walk into the airport coffee shop and proclaim that he never checked his fuel tanks visually. Hmmm. I don’t see any hands in the air. I could cite hundreds of examples where pilots have clearly acted in ways not only contrary to safety, but in the most basic unsafe ways.

The psychology of learning holds that humans learn through three “domains of learning”. The first is the cognitive domain that includes our academic type knowledge. This would include the knowledge that the airplane requires fuel to continue flight and our ability to calculate the amount of fuel required for a given flight. The second domain is the psychomotor domain. This one includes our ability to manipulate controls, switches, etc. Our ability to fly a coordinated turn or physically switch the fuel tank selector valve is included here. The third domain is the affective domain. This one is often overlooked, but can also be the most critical. It encompasses our acceptance or internalization of the principles contained in the first two domains. In other words, our level of achievement in the affective domain determines whether we simply talk the talk or actually look in the fuel tanks, plan and adhere to fuel reserves, avoid IMC when operating VFR, remain vigilant of traffic, etc. Pilots who are high achievers on the affective domain talk the talk but also walk the walk. It is not enough to know how to operate safely. Pilots must actually follow the safety procedures that we all have been taught.

This attitude of safety fostered by high achievement in the affective domain is perhaps the greatest single safety factor available. It doesn’t make flying less fun. The increased confidence produced by knowing that safe practices have been followed throughout the preflight and in-flight phases makes the flight much more enjoyable.