Originally Posted by
JohnDixson
004, One other thing that has me puzzled is a subject I’m a rank amateur at: to whatever standards were set up, the Army tested the Comanche re radar and IR detectability and as far as I know, it passed. Comanche main rotor is oriented edge on looking forward. Now the tilt rotor 280 has its blades ( propellers ) oriented with flat areas lookiing forward. Then again so does the V-22 so does radar cross section not matter?
But then again, Bell initially presented a smaller FARA sized tilt rotor idea, but since have reverted to the Comanche look-alike Invictus. Curious.
If you look at photos of the Osprey in cruise flight it is clear that the rotor blades are not "flat areas looking forward", as the highly twisted blades are themselves operating at a high pitch angle. The end result is the blade presents no flat area to the front in cruise flight with the root of the blade being edge on and the tip being around 45 degrees to the direction of travel. Thus the Osprey's rotor present a very stealthy "faceted" perspective to any radar in the frontal (or rear)arc.
Bell initially presented a smaller FARA sized tilt rotor idea, but since have reverted to the Comanche look-alike Invictus. Curious
Bell's initial LHX proposal was the BAT
Bell BAT helicopter - development history, photos, technical data
Like the LHX before it, the FARA requirements were dumbed down enough to accommodate the short comings of the X-2 technology that a tilt rotor was not needed and, therefore, would be at a disadvantage due to cost/weight. It will be interesting to see if Sikorsky miscalculated and had the FARA requirements scaled back so much a more traditional helicopter could meet them.