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From: arthur@Eng.Sun.COM (Arthur Leung)
Newsgroups: sci.military
Subject: Re: Carrier Aircraft
Message-ID: <1991Mar14.042254.29658@cbnews.att.com>
Date: 14 Mar 91 04:22:54 GMT
Sender: military@cbnews.att.com (william.b.thacker)
Organization: AT&T Bell Laboratories
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From: arthur@Eng.Sun.COM (Arthur Leung)
From igor!yoda!wab@uunet.UU.NET (Bill Baker)

>     Isn't one of the advanced fighter candidates incorporating thrust
>vectoring?  It seems like I read this in an article.  Wouldn't that
>permit much lower sink rates for carrier landings?  The main problem
>of converting land-based aircraft, historically, has been the airframe
>and landing gear relative weakness.

that's the YF-22A built by lockheed, boeing, and general dynamics.
the vectoring is in pitch only as the vectoring system is based
on paddles that deflect into the engine tailpipe.  it's not a
fully vectorable system as used on the AV-8.  

this vectoring system is used for high angle of attack operation.
according to aviation week,  AOA of 60 degrees have been flown
with excellent controllability.  relatively high rate of roll at
high AOA and high pitch response are other gains.

>I've always assumed that the
>reason the F-4 converted so easily to carrier flight was that it was
>built like a tank anyway.

well, mcdonnell douglas had a contract with the navy *first* and
the air force was told to take it after it was shown to be
a pretty hot plane.  i believe the air force version retained the
navy arresting hook and folding wings.

>     I would think that, regardless of whether they procure a version
>of the ATF, the Navy would insist on thrust vectoring on the next
>generation of carrier aircraft.  The weight savings from airframe
>downgrading could translate into much more range, more room for
>weapons and avionics, etc. 

the distinction between the "thrust vectoring" of the harrier
and the "thrust vectoring" of the YF-22 (and the X-31) is fairly
clear.  you can't get the latter to jump straight up.

more, thrust vectoring isn't free.  thrust vectoring requires
additional equipment - ducts, paddles, hydraulics, pumps, etc.
it starts to eat into any gains you might get.

dryden has an F/A-18 fitted with thrust vectoring paddles.
what is the weight/other penalty for that?

any experts on the harrier design?  what were the design loads
used in the contract specification?  (eg: "it has to survive an
XXX foot fall on its main gear without damage.")  what tradeoffs
were made for its jump-jet capability?

-- arthur

disclaimer: if i knew anything, why would i be reading this newgroup?