ET's Info-Stew

I recently made a fairly bad landing in my first tail-wind landing experience. I thought it would be instructive to illustrate why.

It is obvious that the groundspeed in tail-wind landings is much greater than for head-wind or no-wind landings. This additional ground speed creates an illusion that the pilot must account for. In Stick and Rudder, the author discusses the idea of “buoyancy”, which for the sake of this discussion is the degree to which a plane will “balloon” when back-pressure on the yoke is applied. Generally speaking, when the plane has a high airspeed, it is quite buoyant. The opposite is true when the plane has a low airspeed.

Generally, a pilot has to have a constant sense of the degree of buoyancy the plane has. This way he knows what kind of control pressures are necessary to get the plane to react as desired. During approach to land, new pilots such as myself rely upon the visual estimation of ground speed to sense this value. We think higher ground speed relates to higher airspeed, which means greater buoyancy. However, this is an illusion, a trick that new pilots fall for (literally).

In the high ground speed situation of a tailwind landing, I estimated that I had a significant amount of buoyancy when flaring and thus applied a small amount of back pressure. However, since my airspeed was appropriate for normal approach, the plane was not as buoyant as I expected. As a result my insufficient amount of yoke back pressure did not reduce my descent rate and the wheels hit the ground hard.

To correct this, the pilot must have a sense of buoyancy that does not place visual estimation of ground speed as the primary factor. The Stick and Rudder author suggests frequently testing buoyancy with minor applications of the yoke. The degree to which the plane reacts to these mini-tests gives the pilot an excellent feel of buoyancy.