On the taxi strip coming back in to the hangar area I was taxiiing at about 10 mph into a 10 mph wind. The airspeed indicator was bouncing between 20 and 22mph. I decided to look for the aileron effect at this speed. Oscillating full left and full right with the stick the wing tips could be rocked an estimated 4 inches up and down (total excursion of 8 to 12 inches, the more significant when it is understood that my gear is quite stiff and wide. It has the Fisher spring kit. No doubt this is added evidence that there is considerable force available to the pilot to counter wing lift situation (wing lifts in a cross winds, is a major reason for experienced tail dragger pilots to still have a loss of control on landings. In that case a crosswind gust can lift a wing and full aileron will not be enough force to bring it down. If this continues for just a very short time loss of directional control is almost sure to follow.
I had in previous times worked this same exercise and could just barely see a response at the wing tip.
Today I flew in calm weather shooting several takeoffs and landings most on asphalt and the last on grass.
While at altitude I tried a near full power (2400 rpm ) stall straight ahead. Slow decelleration until stall, indicated airspeed 24mph and plane at a vertical pitch attitude so extreme as to be disconcerting. I felt it was near 60 degrees. The break when it finally came was very sharp, ( the bottom just dropped out). It did drop straight ahead.
I have been flying for a long time and and a cfi for a good part of that time. I was not greatly surprised by the quite dramatic downward pitch as I expected it, however it was the most complete and full break I have ever experienced. The Mfgr of Feathers vgs told me that when a full stall occurs with vgs it will result in a "sudden break". He is correct.
I guess this is not surprising as vgs keep the air attached to the entire wing more than is ever possible with out them. So when finally the break occurs it is complete and total across the entire wing.
The recovery was without incident as the pitch down was straight ahead. I did not observe the altitude loss. In due time I will perform it again with more care to watch rate of climb or loss just prior to stall break or the altitude loss.
Later I practiced stall approaches at 1500 rpm and it again repeated to be 27 mph indicated air speed. and 1000 rpm and again it repeated to be 31.5 rpm. In these last two I had full back stick with constant rpm would not get a stall break.
Tom Marsom, Wisconsin, USA.
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