That still seems a bit long: that revised calculation gives 307m to stop
after a 33kt touchdown: this number assumes I flew finals at 55kt on a
calm day before rounding out for a fully held-off landing in my 201
Libelle, which stalls a little below 35 kts, so 33kts seems about right
for the speed at which the main wheel hits the floor.


Martin--
I'm not quite sure where we're diverging. Here's my math: 33kts *.511m/s / kts = 16.9m/s. 16.9^2/12 = 23.8m.

However, and this is a big however, this is not an analysis of a plane's best possible touchdown. It's a rough estimate for modern glass ships to show how short the stop would be if the ONLY consideration were not nosing over AND your elevator beingÂ*nonexistant. This calculation relies on several implausible factors, several of which you rightly point out. You'd have to have no wing lift (in order to place weight on the tire); no elevator lift (theÂ*premise of the question); you'd have to have great tire/surface friction (in order not to lock up the tire); there should be no other drag (or else we'd stop even faster!); your braking system would have to be up to the task (hah!); etc...

It's only useful so that we know if we should look at the main/tail wheel mass distribution as a limiting factor in braking distance. The stark difference between the optimal and the real-world numbers (10x!) let us conclude that it is not.