jim:
we'll have to agree to disagree. i have been flying power for over 15 years,
all sizes, .40 to 150cc and i can count the number of "tip stalls" i have seen
on take-off on one hand. as long as there is sufficient airspeed over the wing,
with or without washout doesn;t make any difference. an airplane that is
horsed off the runway too fast may snap because the wing isn't flying, and
while it looks like a tip stall, the whole wing is stalled. even still, this
condition is going to be limited airplanes that have minimal wing area, tend to
be heavily loaded, and have wings that have poor load speed performance, and
may be underpowered or improperly propped - yes - there is such a thing. it is
also more common on smaller planes of the .60 and small variety. i also fly
scale gliders, (see Dec RCM) and every one has washout. gliders fly right
above stall speed, and with the high aspect ratios too much down aileron could
stall the tip. so we use a lot of differential and have negative incidence
toward the tips - also called wash out. But wash out has very little
application in power, where the flying speeds are higher, and the low aspect
ratio wings with thick airfoils are far less susceptible to low speed stalling.
it also ruins aerobatic performance. as far as landing, the classic landing
snap is turning upwind and simply not having enough energy behind the airplane.
the pilot feeds in too much elevator, and over she goes."tip stall" becomes
the curse, but i doubt on 99% of these crashes wash out would have made any
difference. it's pretty easy to watch someone on approach get ready to lose an
airplane - the airplane gets mushy, the nose comes up, and boom. speed is
everything.
P