Small Talk

摘要

Very early in the development of the airplane it was discovered that a vertical tail was necessary for stable flight. It has been argued over the years whether the rudder was necessary to correct the defect in the aileron control or whether the aileron was necessary to correct the defect in the rudder control. In many respects dihedral will make the rudder produce the banking effect of the ailerons, but before it does so, a slip must proceed the banking effect. None of the above negates the necessity of a vertical tail. All of this is leading to something I did the other day that caused me some embarrassment and started me thinking. The embarrassment is easy to handle because one gets used to it, but the thinking is difficult! I had just completed an electric project that was giving me a bad time. It used two servos in the wing (one for each aileron) that were joined by a "Y" connector, and they "talked" to each other causing all kinds of jitter in the whole system. When that was finally fixed, the airplane was ready for a real test flight. The test flight consisted of a nice smooth take-off with a strong climb followed by uncalled for turns and other things that resulted in a spiral into tall grass and wet ground. The damage to the airplane was minimal; the vertical tail separated from the fuselage and hung by the pushrod and the control horn. Since the airplane came to rest without tumbling, it seemed strange that the fin/rudder would have come off! I naturally blamed radio problems as well as myself, and it wasn't until back in the shop that I realized the real problem. The tail skid was missing!