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Lessons Learned
We are analyzing this crash not to denigrate the pilot involved, nor her instructors, but rather to see what we can learn from it so something similar will not happen to us.
If you watch the video again you will see that the initial loss of control was almost certainly due to not having the stick all the way back. Not having the stick back allowed the tailwheel to bounce and skip along the surface, rendering it useless for steering. When a crosswind gust hit, correct rudder input was instantly made, but without tailwheel assistance the rudder lacked sufficient authority to counteract the gust. Had the tailwheel been held firmly down by holding the stick all the way back, it would have provided significant additional steering authority, probably preventing loss of directional control.
Even without tailwheel steering, this accident could have been avoided by steering with differential braking, a far more powerful steering resource than either the rudder or the tailwheel. Or power could have been applied the instant it became clear that the rudder lacked sufficient steering authority. Adding power would have increased airflow over the rudder, thus giving it more steering authority, and by eliminating the deceleration it would also have eliminated any tendency to ground loop.
This pilot did eventually get the stick back and add power, which, together with right rudder previously applied, actually stopped the ground loop and started the Cub turning back toward runway heading. Unfortunately, the added power also caused the plane to lift off before the pilot was mentally prepared to fly. Full power and full nose-up trim caused an immediate pitch up from the three-point liftoff, and the pilot did not apply enough forward pressure on the stick to overcome the nose-up trim force and get the nose down in time to avoid a stall. She reflexively applied left aileron to bring up the dropping right wing, but that just made things worse by commanding a spin to the right. The right wing tip then contacted the ground, possibly saving the pilot’s life by preventing the plane from spinning to inverted before the crash.
There are several lessons to be drawn from this crash. The first lesson is that ground loops happen quickly, so quick reflexes are required to prevent losing control. Conscious decisions take too long. The longer it takes, the farther out of alignment the airplane gets, and the harder it is to get it back into alignment.
An equally important lesson is that the airplane is very controllable and can recover even from a fairly well developed ground loop if correct control inputs are made. This pilot actually stopped the ground loop and began turning back toward runway heading before the aircraft lifted off.
Another lesson is that adding power is a great way to retain or regain control. The added prop wash gave the rudder much more steering authority, and the forward thrust instantly eliminated the ground loop tendency. However, a corollary lesson is that when you go to full power you must be mentally prepared to fly, especially with a lightly loaded wing like this Cub had.
The most obvious lesson to be learned from this crash is to hold the stick all the way back upon touching down in three-point attitude. Keep that tailwheel firmly on the ground so you can steer with it.
Another lesson is that it is best not to land with full nose-up trim, in case you have to go around. In a nose-high liftoff, getting the nose down immediately is key to avoiding a departure stall, and full power together with full nose-up trim makes it much harder and much more crucial to get the nose down quickly.
Yet another lesson demonstrated here is that a dropping wing is best brought up by rudder, not aileron, because a down aileron serves only to deepen the stall of that wing while the up aileron on the opposite wing helps delay its stall, thereby commanding a spin entry. Bringing up the dropping wing by application of opposite rudder while simultaneously unloading the wing will prevent both the spin and the stall.
A corollary lesson is that vulnerability to gusts can be avoided by making tail-up takeoffs and landings. When a premature nose-high liftoff is caused by a gust that quickly subsides, the resulting sudden loss of airspeed can make a stall, or at least a touchdown, inevitable. The extra speed required for tail-up operations provides a cushion against a stall when the headwind suddenly drops out from under you.
All of these lessons are reviewed in more detail in my book, The Art of Avoiding Ground Loops. More importantly, The Art of Avoiding Ground Loops identifies fourteen essential taildragger reflexes every pilot needs in order to avoid accidents like this one. And it provides a safe and logical way to develop these reflexes prior to testing them in a landing. For more information on this, see the Taildragger Reflexes page.
