John Carrier wrote:

Ed Rasimus
Maybe some Tom-drivers in this forum will comment, but I've got to
think that in a head-to-head pass with a system lock at ten miles
there is no possible way that the AIM-54 could function.

It's well inside Vmin for a AIM-7E-2 and wouldn't be a viable shot for
an AIM-9J, P, or M.

I think your memory is cloudy. 10NM is nicely within the AIM-7 envelope.

Indeed. Lodge/Locher (Oyster 01) and Markle/Eaves (Oyster 02) got an in-range
light at 13nm and made their first launch at 8nm FQ (approx. 135 deg. TCA,
target angels 13, snap-up) on 10 May 1972, and Lodge fired again at 6nm when the
first AIM-7E-2 blew up at motor burn-out. Min-range for AIM-7E or maybe E-2 is
12,000 feet head-on (firer and target speeds and altitudes not stated, but I'm
guessing M0.9), according to one Air Force report. Here's some data from the
SAC for the earlier, less maneuverable, and shorter-ranged (due to a lower total
impulse motor and less-sensitive seeker) AIM-7C, the first SARH Sparrow version,
culled from a post by Pete Stickney a few years back:
---------------------------------------------------------------------

The motor is the same Aerojet 1.8KS-7800 used on the Sparrow I and
Sparrow II. The motor performance is roughly that of the AIM-7D.
The autopilot has a G-limiter that holds it to 15Gs.

Launch limits a Altitude 0 to 60,000', and max launch speed is Mach
1.3. The range diagrams are for a launch speed of Mach 0.9, and
target speeds of Mach 0.7 and Mach 0.9. (It's fascinating to see how
much the max range decreases with altitude. Max range vs. a Mach 0.9
target head on at
sea level is 'bout 19000', min range about 9500.
At 30,000', the correspondng numbers are 34,000' and about 9500'.
At 50,000', Max Range vs. a Mach 0.9 target is 'bout 37000', min range
14250'

Tail chase, vs. a Mach 0.9 target (Co-speed)
Sea Level: Max Range 5700', Min Range 2000'
30,000': Max Range 21000', min range 'bout 4200'
50,000': Max Range 25000', min range 8200'.
-----------------------------------------------

It's pretty clear that head-on Vmin is well below 10nm for an AIM-7E2



It's also in the heart of the AIM-54 ACM Active mode envelope IIRC.


And, inside ten miles, even a MiG-21 can be easily acquired visually.

Head-on @ ten miles? Not with these eyes when they were 20/15 and on a good
day. Of course, the T-38 (and to a very slightly lesser degree, the F-5)
were more difficult still.

Yeah, considering typical tally distance on MiGs in Vietnam was 1.5-2nm.
Practice with F-5s/T-38s or A-4s helped, but it sure didn't make head or tail-on
pickups at 10nm 'easy'. By all accounts 5nm would be unusual, with the average
perhaps 2-3nm.

Guy