Is there a single major redundant aspect in a (single-rotor) helicopter's ability to stay airborne?
I thought helicopters were so expensive because every part had to work and last, or else.
I thought helicopters were so expensive because every part had to work and last, or else.
Yes, but the key to why helicopters are expensive is that is that aviation is highly regulated by the government. Individual manufacturers, pilots, airlines, etc. don't get to decide what is "safe enough," they have to obey the standards set by the law. Adhering to the standards of the law requires a lot of process and paperwork.
Just gaslight the regulator and produce the best selling airframe of all time.