John Carrier wrote:
"DDAY" wrote in message
.net...

I read somewhere that the Navy used rifle scopes in some of its fighter
jets
for spotting other planes. Is this true? And were they mounted in the
cockpit or used like binoculars?

Done on the Phantom in some squadrons. Lined up with boresight.
With radar
lock and bogey on the nose, you'd lean forward and get a magnified
view and
hopefully an early VID. Somewhat awkward to use.

F-15 units were big on the practice, too, starting with the
AIMVAL/ACEVAL tests of 1977. One account is in Cecil Anderegg, _Sierra
Hotel_ (USAF History and Museums, 2001), p.161:

[...] The F–15, surprisingly to some, did not have the powerfully
magnified telescope, TISEO [Television Identification System,
Electro-Optical], that the F–4 carried. TISEO allowed the F–4 crew to
see what the radar was locked to and identify targets from many miles
away. The idea of TISEO was to give the crew enough time to identify the
target visually in order to fire a Sparrow before the target could shoot
at them. Since they had no such system, the F–15 pilots were
hard-pressed to get a Sparrow shot off before minimum range when the
rules of engagement required a visual identification. Often, they could
see the F–5 in the TD box as a black dot, yet still not positively
identify it until it was too late to shoot. Blue Force pilots rigged a
simple piece of equipment that made their problem much easier to solve.
They purchased a standard telescope of the type used on hunting rifles
and manufactured a bracket to attach the scope to the side of the HUD
glass. On the HUD was a “W” symbol that always showed exactly where the
nose of the airplane was pointed during flight. Before takeoff, the
pilot would note where the W was projected on the ground in front of his
aircraft. He then leaned forward and used two small adjusting screws on
the scope bracket to tweak the scope to exactly that same place. Then,
in the air, when the radar was locked to a target, he had only to fly
the W so that it was exactly over the TD box, then look through his
rifle scope. If he did those things carefully, the target would be in
the scope field of view, and he could identify it in plenty of time to
fire his Sparrow. The Blue pilots nicknamed this clever modification
Eagle Eye, and it quickly swept throughout the growing F–15 community.
It was not long before every F–15 awaiting takeoff at the end of the
runway at Langley or Bitburg had a rifle scope attached to the side of
the HUD.

[https://www.airforcehistory.hq.af.mi...erraHotel.pdf]