This one is too absurd to pass up without comment.
I was going through the NTSB reports for helicopters today, looking for a specific accident in Arizona that hasn’t yet been listed on NTSB.gov. I did, however find this report that seems to indicate a training problem with a solo student pilot that has 64 hours of helicopter flight time:
According to the pilot, she departed Frederick Municipal Airport (FDK), Frederick, Maryland, about 0745, with an intended destination of Lancaster Airport (LNS), Lancaster, Pennsylvania. The pilot reported that she conducted the cruise portion of the flight at an altitude of 3,000 feet above mean sea level (msl), at an airspeed of approximately 110 knots. After she established communications with the LNS air traffic control tower, and was getting ready to begin her descent to the airport, the pilot noticed that the vertical speed indicator was indicating a descent of approximately 1,000 feet per minute, and that the airspeed was approximately 120 knots. The pilot “raised the collective” pitch control in an effort to reduce or stop the descent, but the helicopter did not respond as the pilot expected, and the descent continued. She determined that she would not be able to reach LNS, and selected a field suitable for a landing. The helicopter landed hard in a soybean field approximately 8 miles west-southwest of LNS. It remained upright, and the engine continued to run after touchdown, until the pilot shut it down using normal shutdown procedures.
The preliminary report goes on to say that when investigators tested the aircraft’s engine, they didn’t find anything wrong with it. It was up to date on all maintenance, the fuel samples were clear, and there was no evidence of a problem.
Is it me or is the problem as simple as what can be gleaned from the above-quoted paragraph? Let’s review:
- The helicopter was descending at 1000 feet per minute, which is pretty quick, but not nearly as quick as an autorotation or a steep descent from altitude. (I commonly descend at at least 1500 feet per minute when coming off the Weaver Mountains (4500 feet) to Congress (3000 feet) toward Wickenburg (2400 feet).)
- The helicopter’s airspeed was up to 120 knots from 110 knots. That’s fast, even for an R44. I normally cruise at 110 knots when alone; I have to push pretty hard to get it up to 120 knots without adding power or beginning a descent.
- The pilot “raised the collective.” Helicopter Flying 101 says that when you pull pitch (raise collective) on a helicopter with a governor or a correlator (or both, as this helicopter has), you’re increasing power.
So the pilot is already zooming through the sky, but she adds power to stop the descent? Doesn’t she understand how the cyclic works? Pull it back to slow down. If you keep your power setting the same, you should also slow your descent rate.
Here’s what I think happened, based on the information provided in the preliminary report and a little research. The pilot was cruising at 3,000 feet. She was “getting ready to begin her descent” to an airport at an elevation of 403 — a required descent of 2600 feet. What she didn’t realize is that she had already begun the descent. Possibly with the airport in sight, she’d pushed the cyclic forward, perhaps to adjust the sight picture of the horizon before her. (This is something I recall doing more than once when I was a new pilot descending from altitude, so I can understand how she might do it, too.) The net result of a forward movement of the cyclic without a power change is to speed up and descend — which is exactly what happened. With a power setting of 18 to 20 inches of manifold pressure, she could easily get into this situation.
Rather than attempt to slow down by pulling the cyclic back, she elected to arrest descent by adding power. This would only make the problem worse if she didn’t add aft cyclic. It was probably a flare near the bottom — perhaps drilled into her by numerous practice autorotations — that slowed her down and enabled her to touch down without slamming any harder into the ground.
What should she have done? As soon as she realized she was going so fast and descending, she should have added aft cyclic. This should both slow her down and reduce her descent rate. It doesn’t matter how much power is available; if the rotors are not stalling, the helicopter will fly. Gentle aft cyclic should enable her to get a better idea of what the problem is — if there is indeed a problem.
But it’s hard to imagine a power problem if there’s no loss of RPM or yawing to the right — neither of which is mentioned as a symptom of the problem. And believe me, if a Robinson has low rotor RPM, you’ll know it — the damn horn starts blaring at 97% RPM; she would have had enough power to fly with RPM as low as 85% (or probably lower).
What do I take away from this? This solo student pilot was not prepared for her solo flight. She evidently did not understand how the controls work together to manage airspeed and climb or descent rates. (This may have something to do with her experience as an airplane pilot.) When she noticed the descent rate and high speed, she possibly panicked and did the first thing that came into her mind: raise the collective to stop the descent. But if she had been properly trained and knew what was going on, she would have reacted properly by simply pulling the cyclic back to slow down and reduce the descent rate.
As a result, a helicopter is destroyed, the NTSB is required to waste time and resources to investigate, and a student pilot, although lucky to be alive, has an accident on her record.