If you unpack 0ufos file in base folder you will find there file named aircraftmanagment, there you can change stats of of ufos, interceptors, dropships. There you can see which craft has shields!
One other thing, sometimes game informs you that pilot died, sometimes dont, so if pilot survived, where is he?
I had one superb pilot (skills), he was shot down, he did not die but where is he ?
i think somone sometime mentioned that pilots who survive should return to base. but its not implemented yet.
dont know how much research of new aircraft changed from 2.4 (now playing 2.6 and i can research dragon interceptor) but if i remember corectly all 3 battle aircrafts you can research only afrer alien propulson. i miss one more aircraft right after alien materials. also some new weapons after alien materials (imporved misiles specialy adapted for fighting aliens). advanced misiles for sam sites...