I am a pilot. And up until recently I’ve always considered myself a pretty “shit-hot” pilot (as we say) of both airplanes and helicopters. I even have my seaplane rating…and owned one! I mean, I know how to fly, and I've been doing it a long time, which has lead to the assumption that I’m good at it despite the occasional-yet-mounting evidence to the contrary. Sadly I was proven wrong yet again this past fall when I got checked out in an airplane that has a tailwheel instead of a nosewheel.
The differences are noteworthy. Although both types of airplanes are pretty much exactly the same in terms of how they fly, the skill needed to land the damn tailwheel airplane is what sets it apart and makes the FAA require that pilots get a separate “tailwheel” sign-off from an instructor before flying them.
Let me explain. Here is my nemesis, the Aeronca Champ.
As you can see, the landing gear of a tail-dragger is pretty far forward – at the very front of the wings right near the firewall where the engine attaches to the fuselage. This is great if you need a lot of clearance for the propeller – like say if you’re operating from so-called “unimproved” airstrips out in the bush, away from smooth and/or paved runways. But in order for the airplane to sit on its tail this means that the main wheels are forward of the longitudinal center of gravity.
So when you come in for a landing a teensy bit too fast and touch down a little too hard on the main wheels only, physics forces the tail of the airplane downward - sometimes faster than you can react. When this happens, the wings go to a higher angle of attack with respect to the relative wind from the front…which generates more lift…which pulls the airplane back up into the air. This is bad. The pilot’s natural instinct is to push forward on the elevator control (sometimes a yoke but often a stick) which forces the plane back to earth. The main wheels hit again, and again the tail goes down, increasing the angle of attack of the wings… Without the proper corrective action, things usually go from bad to worse, with the airplane “crow-hopping” down the runway until something breaks (usually the landing gear).
Also, because the center of gravity is behind the main gear, there is a strong tendency for the plane to “weathervane” into a crosswind or simply “not go straight” on the ground. It’s like trying to throw an arrow tail first. It just doesn’t want to go that way; the heavy end always wants to lead. And if the wind isn’t blowing directly down the runway, or even if it’s light-but-gusty, it messes with you big time.
The “trick” is to come in at an exact airspeed, altitude and nose pitch attitude. You want everything just right, so that you’re mere inches off the runway in a “three-point” attitude, holding the plane there, keeping it from touching down until the speed has bled off sufficiently that the wing isn’t generating any more lift. As the wings give up, the airplane settles softly and gently onto all three wheels. Supposedly. In theory. It sounds simple, but it often is not.
With Dave Sr. in the back seat, he and I went ‘round and ‘round the traffic pattern at the Brewster airport, with him coaching me and announcing all my mistakes – which were plentiful. I have a lot of time in airplanes, but almost all of them are bigger and faster than the Champ, and none of it recent. It’s hard to readjust to flying an airplane so slowly. The wing of any airplane will “stall” (stop producing lift) if you get it too slow, but this Champ had an almost helicopter-like ability to hover. The wings have a lot of lift.
The helicopter pilot in me likes to make steep approaches compared to airplanes, just because they’re safer for reasons too complicated to go into here. To me, the angle of an airplane’s normal glidepath just seems painfully, almost unbearably shallow.
So usually I’d come in way too fast and way too steep. I had a hard time nailing that exact nose attitude needed to stop the descent inches above the runway without clunking right onto it or alternatively ballooning back up in the air.
I did finally “get it” and Dave signed me off, but it was not the piece o’cake checkout I egotistically assumed it would be. It was both challenging and fun. But I’d be lying if I said that at times it wasn’t actually work.
2 comments:
check this out, harvesting Christmas Trees with a helicopter:
http://www.youtube.com/watch?v=SPO9pVwoxVg
For us rotorheads!!!
Ron in New Bern, NC
JetRanger, LongRanger, UH-1B
Bob,
Not only do we have flying old Sikorsky's in common, but also flying Aeronca Champ's. I've flown my Aeronca for over 40 years, taught countless people to fly including my own son and daughter. My favorite airplane to fly out of all the many airplanes and helicopters I have flown. Glad you had the opportunity to fly one.
Chuck
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