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A closer look at a common training procedure
Complying with this obviously does not guarantee it will always be possible to execute a forced landing without damage or injury, but it does improve the likelihood that one can be accomplished under control and with an increased probability of survival.
There is, however, a time when an engine failure will result in an accident no matter how carefully a pilot plans or prepares. This brief period of danger is seldom discussed or considered. It occurs when climbing at VX—the best-angle-of-climb airspeed—while attempting to outclimb an obstacle near the end of a runway. If a pilot experiences total engine failure during the early phase of such a climb, there is a strong probability that there will be a serious accident no matter how much runway remains ahead of the airplane.
Attempting to climb over an obstacle at VX means that the aircraft will be in an unusually nose-high attitude. Should the engine fail at or below 200 feet or so above the ground, the pilot will be between a rock and a hard place. He will have little choice but to lower the nose to avoid stalling. This significant pitch change will produce a dramatic rate of descent. Because the aircraft will be so close to the ground while sinking so rapidly, the pilot will recognize and be alarmed by the rate at which the Earth rises to meet him. He will feel an almost uncontrollable urge to pull back on the control wheel to arrest the sink rate and attempt to flare in time to soften the unavoidable crunch. The trouble is that there will be insufficient altitude to do this safely. The pilot will be a passenger in his own airplane, and the aircraft will simply pancake or belly flop harshly onto the ground. Such an accident most often results in substantial aircraft damage and injury to those on board.
In other words, there usually is no way to safely cope with an engine failure that occurs while climbing at VX near the ground.
A dramatic example of such an accident occurred a few years ago when the pilot of a Howard DGA–15P lifted off from the Kern Valley Airport in Southern California and began climbing at VX. At a height of about 100 feet, he experienced sudden and total power failure caused by the shearing of the driveshaft of the engine-driven fuel pump. What made this accident unique is that it was captured on video. The 16-second footage can be seen by going to YouTube and searching for “Engine failure during climb at VX in a Howard DGA-15P.” Fair warning: The last few seconds are not easy to watch.
Raise the nose? That would stall the airplane and steepen the descent. Hold the nose where it is? That is apparently what the pilot did in this case and wound up holding the airplane in a mushing stall...You will notice from the video that once the engine failed there was no way for the pilot to land without serious damage to the airplane. Raise the nose? That would stall the airplane and steepen the descent. Hold the nose where it is? That is apparently what the pilot did in this case and wound up holding the airplane in a mushing stall while the airplane descended. Lower the nose? That would steepen the descent and worsen the impact. The pilot was in a world of hurt with no opportunity to do much of anything constructive.
The good news is that engine failures are rare plus the time involved in a VX climb is short—lasting only until the aircraft reaches a safe altitude of about 400 feet or more, or until the pilot lowers the nose and accelerates to a safer speed, such as the best-rate-of-climb airspeed. With sufficient altitude or airspeed, the pilot has a much-improved chance of landing straight ahead in case of power failure. It also is fortunate that pilots do not often make obstacle-clearance takeoffs. These factors help to explain why accidents like the one shown in the video are uncommon events.
Those with the greatest exposure to the dangers involved in climbing at VX are flight instructors who teach the maneuver regularly. After all, private pilot applicants are required to demonstrate proficiency in VX climbs during their flight tests. Others exposed to the risks of the VX climb are those who operate routinely from airports bordered by tall obstructions.
I believe it is important for the FAA and the flight instructor community to make pilots aware of the risks involved when using VX to overclimb obstacles at the end of a runway. Personally, I try to avoid the procedure.
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