In-flight failure is not likely
I'd like to ask you about airframe integrity for general aviation planes. I fly a general aviation airplane with between 6,000 and 8,000 airframe hours. The airplane is immaculate, and its systems and powerplant get checked regularly. The other day I hit some pretty stiff turbulence and naturally slowed to maneuvering speed. I began to wonder about an airframe failure. Historically speaking, have there been many airframe failures in turbulent VFR conditions?
Thank you,
C.C.
Greetings C.C.:
It's perfectly understandable that you would worry about the strength of the machine you fly. If you elect to look to statistics for solace in this matter, then your worries are over. First, it is extremely rare to have an airframe failure in an airplane. When this does occur it's usually because the pilot lost control of his or her airspeed. The result is an airframe failure due to excessive G-loading and/or divergent flutter.
Awhile back I reviewed six years' worth of recent accident data, finding something like 46 airframe failures. Forty-four of these occurred when flying in instrument meteorological conditions and began with a loss of airplane control. The result was an excessive airspeed buildup and eventual wing/tail destruction. Only two of the accidents occurred in visual meteorological conditions. One of these accidents might have resulted from an encounter with wingtip vortices from a much larger airplane. As you can see, it's extremely unlikely that an airplane will be damaged by turbulence as long as you fly at or below the maneuvering speed for the weight flown. It's much more likely that a pilot flying in IMC might experience structural failure if he can't control the airplane in these conditions.
To be continued
Dear Rod:
Last week one of my partners took the practical test for an instructor rating. More than four hours into the oral, the examiner discontinued the procedure for no apparent reason, saying, "We will finish up next week." That in itself, while being somewhat strange, is not too serious, but another part of their discussion (albeit secondhand) really concerns me.
During their discussion the FAA examiner asked him how much time he would be instructing. The truthful answer was: only occasionally, because of his fulltime business. The examiner said that the FAA was avoiding awarding CFI and CFII credentials to persons who would not be instructing full-time.
What gives? We need every qualified instructor we can get, even for a few hours.
Thanks,
Tom
Greetings Tom:
Don't believe everything you hear. There is no policy whatsoever that prevents an examiner from passing a CFI applicant who doesn't intend to instruct full-time.
The perpetual student
Dear Rod:
I've been a CFI for one year now at a small Part 61 FBO. I have several students and am really enjoying what I'm doing. However, I have one student whom I believe someday is going to be a statistic. He soloed in 70 hours, but that's about all he can do. Whenever he goes to the practice area, he is always asking for vectors from ATC back to the airport. I've questioned him about this, and he just says he is just doing it for traffic advisories (which I don't believe). We've been on two cross-countries, and not once did he find the designated airports. He still can't navigate to a VOR. I must have spent at least 15 hours on the ground and in the air discussing this. He seems to understand it, but he just can't perform in the air.
I am this student's fifth instructor. I feel quite badly about this since it is costing this guy tons of money. He believes that he'll get his certificate in 10 more hours, and I'm thinking he never will. I had him fly with another instructor (who was much more critical than I), and he concurred that my student's navigational skills were poor. My student just told me that he didn't like that instructor. I would just like your advice. Should I keep letting him fly with the hopes that someday he'll understand it, or should I tell him that maybe flying isn't for him? He's already invested over $7,000, and he continually tells me about that. I know that money is an issue for him too.
Sincerely,
Mr. D.
Greetings Mr. D.:
If your student isn't capable of flying safely, then you have a responsibility to discourage and/or prevent him from continuing flight training. If I assume that your student has been given the best instruction possible, then it sounds like he just isn't capable of grasping the essentials of VOR or pilotage navigation. Given this conclusion, your challenge now is to get him to agree with this assessment. A good way to do this is to give him a "make or break" navigation test. Here's one way to do this.
Express your concern about his inability to navigate and offer to let him demonstrate his navigational skill one final time. Make sure he understands that his inability to acquire navigational skills is not at all normal given the amount of training he's received. Make it clear that this flight is a test - not just another lesson - since he's obviously had a reasonable amount of instruction at this point.
Next, devise a test that evaluates his pilotage and VOR navigation skills but doesn't permit the use of ATC advisories. Let him know that a failure to pass this test (based on a definition of failure to which you both agree beforehand) means that you will discontinue his flight training for his own safety. On the other hand, successful completion of the test means that you'll consider continuing his training. The secret here is to make him part of the decision-making process. If he fails - which is almost assured - he may be disappointed, but at least he can't make a case that he wasn't part of the decision. This will also make it easier for you to discontinue his training, if appropriate.
As a final note, you might be able to salvage his flight training investment by preparing him for the recreational pilot certificate. This certificate doesn't require the use of electronic navigation systems. Instead, it requires a demonstration of skill in using pilotage and the magnetic compass. Only you'll know if this is a viable option.
Track up vs. north up
Dear Rod:
I have a student who elects to hold his sectional chart in "track up" mode. I prefer for him to hold it north up, so he can more easily read the airport information and accompanying symbology. I've tried to get him to hold it my way, but he always reverts to his holding preference. He's even threatened to throw up if I don't let him have his way. Is there a problem with students holding the chart in the "track up" mode?
Sincerely,
Frank
Greetings Frank:
Some folks have a hard time visualizing their ground track when looking at a chart held in the "north up" mode (unless they happen to be flying north). It's much easier for them to hold it "track up," which allows them to more easily compare the chart with the outside terrain. This is why GPS manufacturers allow a user to select either "track up" or "north up" on the moving- map display. In either mode, the typical GPS display still provides readable map symbology. I've never experienced a problem with students holding the chart in either manner, even though charts (unlike a GPS) cannot instantly invert the symbology and legends. As long as your student doesn't receive so many paper cuts that he bleeds himself into unconsciousness, he should be just fine regardless of how he holds a chart.
Since your student has threatened to throw up, I recommend the use of a full-body barf bag as a precaution. This is a trash bag with holes cut out for hands and feet with the opening at the top. Insist that your student wear this bag during the flight. If it looks like he's going to give it up, then pull the bag up over his head and tie the top in a knot. Works every time.
Seriously speaking, the real measure of whether track-up is correct for your student is whether or not he knows where he is and gets where he's going. If he does, he knows which end is up, and I'd leave him alone.
Aillerons in stall recovery
Dear Rod:
I'm a flight instructor, and I'm a little confused about what to tell my students regarding the use of ailerons during stall recovery. One instructor at the flight school forbids his students to use any aileron to help lift a lowered wing during stall recovery. He suggests that it can result in a spin. What stall recovery technique would you recommend if a wing drops during a stall? Would this be different from the spin recovery technique that you would also recommend?
Sincerely,
Jan
Greetings Jan:
Most of the general aviation airplanes that we fly have wings designed so a stall progresses from the wing root to the wing tip. This is a common characteristic of rectangular and tapered wings. Once the airplane stalls, the ailerons still have some effectiveness and can be used to help raise a wing. There's nothing wrong with using a little aileron to raise a lowered wing as long as you do so with the coordinated use of rudder to maintain directional control. You just don't want to be too aggressive with aileron usage during stall recovery. For most airplanes, the correct stall recovery technique is to apply forward elevator pressure to decrease the angle of attack, apply full power (if "full" power is appropriate for your aircraft), and use aileron and rudder in coordination to maintain directional control.
I recall one of my students who failed to release elevator back pressure during stall recovery. This particular airplane settled into a deep mush and a wing lowered about 10 degrees. Forgetting the proper recovery technique, she promptly twisted and turned the ailerons (which were completely ineffective in this aggravated stall) in an attempt to raise the lowered wing. Thinking that I had somehow disconnected her flight controls, she reached over and grabbed my flight controls. The point here is that she wouldn't have had this problem if she had decreased the angle of attack first. If I recall correctly, I believe I looked over and said, "Barbara, flight controls are not something pilots share."
Remember, we're speaking about stall recovery here, not spin recovery, which has a slightly different recovery technique. To recover from a spin in most airplanes, you'd reduce power to idle, neutralize the ailerons, apply rudder to stop the rotation, and then apply forward elevator pressure to break the stall.
Rod Machado is a flight instructor, author, educator, and speaker. A pilot for 32 years and a CFI for 28, he has flown more than 8,000 hours and owns a Beech A36 Bonanza. Visit his Web site.
Related Articles
