gwh%headcrash.Berkeley.EDU@ucbvax.Berkeley.EDU (George William Herbert) (09/20/89)
From: gwh%headcrash.Berkeley.EDU@ucbvax.Berkeley.EDU (George William Herbert) In article <27334@amdcad.AMD.COM> gt0818a%prism@gatech.edu (Paul E. Robichaux) writes: > >Stealth aircraft (i.e. the F-117A, B-2, and forthcoming ATA) depend on >their "invisibility" and reduced electromagnetic signatures to accomplish >their mission. Reduced radar cross-section, IR emission, and active emissions >help to accomplish this, but, as with all design objectives, there's a trade- >off made between being "low-observable" and being (manuverable/fast/able to see >/pick your own.). True, but you go off from this with faulty data below... >One good way to reduce radar cross-section (RCS) is to fair the cockpit inside >the fuselage. Unfortunately, this leads to reduced visibility and spotting >potential. For these aircraft, designed for specific, limited missions >(i.e. operating in places where it's critical to not be seen *at all*), >invisibility is the most important design factor. All other design decisions >were made with that in mind (thus the F-117A's slow speed and the B-2's >high cost.) Pardon, but the F-117 is by no means slow. It is subsonic by decision of safety folks because of an engineering problem with the tail fins. It is quite capable of and has often flown supersonic, and will again when the airflow impact problems with the V-tail go away, or they improve the Engineering on some parts. >Note that even "stealth fighters" (i.e. the ATF, F-117A) depend on being >unseen to accomplish their mission. They are *not* air superiority fighters, >so they must depend on friendly air cover, low signature emissions, and >good weaponry to stay alive. Pardon, but none of the things i've seen published about the ATF indicate that your generalizations are true. It is supposed to be a mid-sized (about F-18 sized, perhaps bigger) high performance (as in _better_ than current planes) air superiority fighter, with stealth characteristics. It IS NOT supposed to give up combat potential for stealth. The stealth was secondary, though they did trade off possible improvements over current agility etc. for stealth. It is by no means dependent on not being seen any more than a...F-15 for instance. -- George William Herbert UCB Naval Architecture Dpt. (my god, even on schedule!) maniac@garnet.berkeley.edu gwh@ocf.berkeley.edu