"Ed Rasimus" wrote in message
...
On Wed, 25 Aug 2004 12:06:21 -0400, "Tony Volk"
histoo wrote:

Here's an interesting tidbit that I got while reading Airtime's book
about the Phantom (looks great so far). Apparantly, during the
preliminary
design stage, McDonnell and an aide went around talking to naval aviators
to
see what they wanted. Then, they talked to the aviators' wives about
what
their husbands told them that they wanted in a fighter. Apparantly, when
alone, the pilots generally talked about wanting a hot-rod, single-engine
fighter. But, when with their wives, they mentioned a preference for the
safety of a twin-engined fighter. So, Mr. Mac built the F-4H prototype
to
have two engines.
Does anyone know if this story is true? Is there currently a strong
preference for two engines (e.g., comparing the F-18E to the JSF).
Cheers,

Tony

Highly unlikely. First, consider how often fighter pilot's sit around
discussing with their spouses the preference for number of engines on
their jet. I've tried two wives and never discussed engine count with
either. It isn't a hot topic.

Second, two versus one isn't all the reliability advantage it's
cracked up to be.

And aint that the truth! Anyone who's done some basic reliability calcs will
see it isn't going to make a huge difference when both are burning
simultaneously. If you factor in the probability that what takes out one
engine may take out both or, if one goes it may decide to lunch the other
(or some key component nearby) then it narrows down heaps.

Now get past survivability and look at operational availability and turn
around time. Twin engines are going to cost you heaps in both areas, unless
you like going on missions missing an engine.....

There's the problem of increased complexity and
increased probability of a critical component failure. There's the
system maintenance cost and the greater incidence of an aircraft being
unavailable for an engine problem. While two engines are great in a
training environment, they don't offer that much more in combat (at
least in that historic time frame.) My experience with both single
engine and two engine airplanes over North Vietnam was that an F-4
that suffered battle damage to an engine usually lost the other engine
shortly thereafter due to fratricide from the breaking up engine.
(There are exceptions to every generality of course.)

BINGO!


But, third, and most likely issue is take a look at the immediate
predecessor from MacD--the F-101. Taken side-by-side there is a clear
generational development picture. Two engine, two place, big radar,
interceptor, etc. Add a bigger wing with BLC for lower wing-loading,
eliminate the T tail and droop the slab to correct pitch-up and you've
got a Voodoo become Phantom.

Competition currently between one and two engine drivers is usually
related more to mission and performance rather than dependability of
motors.

But it's interesting how the two engines is better for reliability argument
is used to justify buying one type over another.


--
The Raven
http://www.80scartoons.co.uk/batfinkquote.mp3
** President of the ozemail.* and uunet.* NG's
** since August 15th 2000.