Not Drone related, but here is the way to fix a sealed motor for a typical ICP, HEIL and many other brands of Air Conditioner coil cooilin fans.
OEM ICP Heil Tempstar Emerson 1/3 HP 230 Condenser Fan Motor 1085926 HQ1085926EM
A more detailed look if you need to replace a blower fan (inside a furnace, etc.) is at:
http://tinyurl.com/lwmnkoh

Here is the new replacement motor for this particular setup:
https://amzn.to/2IHhrQK

Arcoaire
Comfortmaker
Day & Night
Grand Aire
Heil
ICP Commercial
KeepRite
Lincoln
Tempstar