Originally Posted by
The oSultan
Been waiting for someone to state the obvious. The area of discussion on bird strike is not exposed except at low speeds at which a strike poses no risk. At speeds that might be worthy of concern the aircraft is fully converted and the area is protected by the nacelle.
Sultan is correct, but even on conventional airplanes and helicopters the aircraft structure provides almost zero system protection from bird strikes. If the structure was strong enough to withstand a 2 lb bird at Vmax and shield all the systems underneath, the aircraft would be to heavy to leave the ground. Instead critical systems are installed in locations behind massive components (like gearboxes) or sacrificial components (like non critical avionics boxes). Where this cannot be accomplished redundant systems are employed with adequate separation to prevent a common mode event effecting multiple systems.
As far as dust and debris entering the open area, have you ever seen the inside of a landing gear bay? Landing gear bays are packed full of wiring, hydraulics, and other systems to provide easy access. And landing gear bays are one of the dirtiest areas on an aircraft. We just design the system installations for the environment.
So why blur out the open area of the pylons? Maybe it is just some marketing executives aesthetic tastes are compromised by the sight of system installations. Personally I am fond of the looks of the skinless Bell 47 that hangs its systems out for the world to see. Beautiful!