So basing off another comment. Have the Ejection seat tied to the rotor and shaft (not in a way that the chair spins. Duh)
Then (as long as rotor hasn't disintegrated) you can eject the seat with the rotor, thus minimizing filet chances... Whilst also floating to the ground softly like those whirly paper helicopter things you played with as a kid
Nah, just do it like they did in WW1; synchronize the ejection to the rotor blades so you fly through the gap, clean as a whistle.
(Please don't ask about our experiments with the earlier WW1 method of "Fuck it, just shoot the propeller sometimes, it'll be fine". Turns out that doesn't work so great when you replace bullets with people.)
Some planes did, but early on they mostly just freeballed it. Turns out propellers are really big and heavy, and they can take a few bullets without breaking. Armour actually makes it more likely that fragments of bullets will fly back at the pilot.
It's very rare that a bullet strikes the blade anyway. Bursts were short because ammo was very limited (twenty round strips were common in early biplanes), and the percentage of the space in front of the nose that is propeller is absolutely tiny compare to the percentage that is not propeller. To us its all a blur but to a bullet those blades are basically standing still.