On Tuesday, October 20, 2020 at 11:50:32 AM UTC-4, jfitch wrote:
Have you ever actually flown a glider? It is an innocent question, prompted by the seeming naiveté of your posts. Almost never do you touch down with maximum braking, you brake when you need to, often late in the rollout when the elevator has lost any effect. The reason Tost drum brakes were acceptable in light '80s gliders is any more would put the glider on its nose. An ASH motorglider on the other hand can skid the tire to a stop, because the tailwheel load is well over 100 lbs. If you had flown a variety of gliders you would have experienced this. Nose wheel trainers can have very effective brakes because they cannot nose over. You need to step away from the calculator and fly more.

Since your question was innocent, I'll accept your implicit apology. I don't think anyone here would mind if you made it explicit, though.

On my last aerotow I had a full brake failure predicated by an old habit of always touching the brakes to stop the wheel. In this case, my theory is that the lack of inertia led the system to have a high jerk, snap, crackle, and pop (yes, those are real terms of the art), leading to a cascading failure. My landing was by necessity brakeless and-- no surprise-- it went perfectly fine with a reasonably short roll-out.

Since I'm going to have to repair a fair amount of my landing gear, and seeing as I've got a lifetime of experience working on planes, I want to take a first principles approach to understanding it. I'm not telling anyone anything new by pointing out that in aviation there's always a tradeoff between weight in one area and lower performance in all others. There's always a way to make a plane stop faster (drag chutes, wider and taller tires, bigger airbrakes, etc...), and the challenge in good design is to find the maximal ratio between cost and benefit.

This has been a very educational thread, thanks to all who have participated so far. Despite the few times when we have sometimes lost sight of our civility I have a very clear idea and theoretical foundation for further experimentation.