Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!cbnews!cbnews!military From: shafer@skipper.dfrf.nasa.gov (Mary Shafer) Newsgroups: sci.military Subject: Re: Tailhooks Message-ID: <1990Nov16.053023.22480@cbnews.att.com> Date: 16 Nov 90 05:30:23 GMT Sender: military@cbnews.att.com (William B. Thacker) Organization: AT&T Bell Laboratories Lines: 78 Approved: military@att.att.com From: Mary Shafer From: wb9omc@ecn.purdue.edu (Duane P Mantick) >From: ehr@uncecs.edu (Ernest H. Robl) >>Now, for a question that I didn't get around to asking anyone at the >>airshow: Some of the modern *AIR FORCE* fighters have tailhooks. Are >>these ever used? If so, when, where, how? Thanks. The tailhooks on Air Force planes are used for both approach-end and departure-end arrestments, when there are gear problems. The throttles are in IDLE and the pilot has reduced the landing weight (jettisoned stores, for example). Navy planes are used for approach-end arrestments, as a normal procedure. The throttles are in MIL or MAX and the plane may be carrying stores. Obviously the Navy plane is going to have a lot more energy. I just went down to the hangar and looked at the F-15 and F-18 tailhooks (the sacrifices I make for this group :-). The F-15 is larger and heavier than the F-18 but its hook is noticeably smaller. > This is true. In fact, the F117A has a tailhook. It has been said > that this is for emergency stops only, although I haven't seen > any definative material *yet*. Most people are of the train > of thought that the F117A is too fragile for a carrier landing, > if that is what you are thinking of. In accordance with USAF policy the tailhook is for for emergency arrestments only. This isn't a Navy plane, so no provision would have been made for carrier landings. (Just like the F-15, for example.) BTW, the F-117A is a big aircraft. Think F-111, not F-16. > Some of the impetus for this may go back to some Lockheed tests > on the F104 Starfighter done for the West German Air Force many > years ago - in this case, Starfighters were stopped in short > distances by arresting cables that grabbed the landing gear; > no tailhooks. The tailhook is considerably less likely to > cause problems than a straight-out gear snag, i.e., if you snag > the landing gear unevenly you will stop unevenly and who knows > how that will end up...... This wasn't done just for the German Air Force, it was done first for USAF, since all military F-104s have hooks. Acceptance testing includes demonstration of all the systems on the aircraft; USAF won't take your word for it that the hook works, you have to show them it works. The F-15 Dash-1 has a table of abnormal gear configurations requiring arrestments. Arrestments are not _normal_ procedures; they're done only for emergencies. In fact, they're not even done for all emergencies. Sometimes you make an arrestment, sometimes you don't, and sometimes you eject. > It may be that having an ability to slow a landing aircraft > via the tailhook is desirable if you are trying to design > "stealthy" aircraft. As the designer, you could then leave > out things like thrust reversers, massive brakes, etc., meaning > overall, less metal to generate radar returns *even if* the > plane is in-flight. As a guess, I'd suspect that a tailhook, > even a big metal one, can be hidden inside a radar-absorbing > compartment fairly easily. The airplane has to be landable without arrestment. Otherwise what you would do were the arresting gear not working or the field closed? You don't eject just because of fog at the base. Fighters and bombers don't have thrust reversing. Some have drag chutes, though. -- Mary Shafer shafer@skipper.dfrf.nasa.gov ames!skipper.dfrf.nasa.gov!shafer NASA Ames Dryden Flight Research Facility, Edwards, CA Of course I don't speak for NASA "A MiG at your six is better than no MiG at all"--Unknown US fighter pilot