After looking at this photo with all the grass & straw flying through the air around the helicopter, I starting wondering about helicopter engines & FOD.
Photo © Timo Breidenstein
My first thought was that a helicopter's engine(s) probably don't suffer from FOD because the main rotor blade's downwash of air likely blows any foreign objects away from the chopper .... they've done a good job of blowing a lot of dirt into my face in the past.
However, the engines need to breath in air somehow, so I'm wondering .......
Are helicopters with turbine engines protected from FOD?
If they are, what method of protection is used?
Are there screens that cover the air intakes? (is that a good idea?)
Do turbine helicopters have inertia separators like many turboprops with reverse flow engines do? Can a inertia separator even help during a vertical takeoff & landing? (due to the low to zero forward speed).
I'm sure most turbine helicopters land on clean areas like airport ramps & Heli Pads, but for the ones that need to occasionally land in fields of dirt & grass for the purpose of a Medivac flight, etc .... do they need FOD protection?