All part is very important, because 1 aircraft can ride many peoples.
So should check all of part before flight.
Our company have Auxiliary Power Unit (APU).
This is one of important part of the aircraft. (APU also use in ship and car).
Aircraft APUs generally produce 115V Alternating Current (AC) at 400 Hz (rather than 50/60Hz in main supply), to run the electrical systems of the aircraft.
APU SN P-35510 (This is Borescope Report). Next time will talk about Borescope.