In article ,
Guy Alcala wrote:

Chad Irby wrote:

In article ,
Guy Alcala wrote:

snip

OTOH, I'm pretty sure I've seen photos of F-4s with TERs, AIM-9
launchers _and_ ALE-40s on the I/Bs (the AIM-9 launch shoes
definitely clear the dispenser; I assume the missile tail fins would
also), so it appears that the problem isn't physical clearance,
although I suppose there might be safety limits due to the proximity
of the missile(s) motor nozzle to the pyrotechnics in the ALE-40.

The casing of the ALE-40 was streamlined, far enough back, and thick
enough that a second of flame from a rocket motor shouldn't have caused
any issues, especially since the Sidewinders were further out than the
dispensers. The box was only a foot or so tall, about six inches
through, tapered, and the carts were pretty nicely sealed (and
electrically fired).

Here's a couple of pics of the master dispenser on the left side with a
flare adapter mounted:

http://www.b-domke.de/AviationImages/Phantom/1340.html
http://www.b-domke.de/AviationImages/Phantom/1341.html

Thanks for the links. The only photos I have of ALE-40s on a/c lack the
slanted fairing at the aft end (I assume this is the flare adapter you refer
to). I have one shot from the rear side of the pylon where you can see the
aft end (I/B side dispenser) tilted down with what's clearly the 15
compartment flare interior (the O/B side dispenser has the 30 compartment
chaff setup, and comes back level), but the cover plate bolts and aft side
don't look the same as the one in the photo. Probably just a slightly
different model of ALE-40.

In the "1341" photo above, the wedge-shaped part with "LH" on it is the
left hand flare adapter (from the rear of the pylon). There was a
right-hand adapter for the right side of the pylon (we always loaded
chaff outboard and flares inboard on the George AFB F-4s), and we only
put them on the dispensers when specifically requested to. The wedge
was to make sure the flares went down and away from the speed brakes
(although there was a switch that was supposed to prevent firing when
the speed brakes were extended). The chaff didn't need an adapter,
since the cartridges were smaller and didn't have much solid stuff in
them. When installing the wedge adapters, you had to flip the "F-C"
switch on the side (at the little aluminum square with "F" and "C" just
aft of "2771"), which made the box "think" it had chaff or flares.

The dispenser itself only goes back to the four Phillips screws running
vertically in the 1341 shot. The inboard slave dispenser was even
smaller, and was about 1/3 the volume of the master.

What good would a chaff/flare system be if you could only use it if you
gave up your short-range missiles?

Beats not having them at all, I guess, especially if the main threat
was SA systems and you were going to use the decoys on every mission
but might never need the AIM-9s (and then most likely on egress), but
I agree it would be less than ideal. If push came to shove, I'm sure
the pilot would say 'screw it' and fire anyway, if their were no
interlocks which prevented that.

The only interlock on the ALE-40 was the speed brake switch (with the
safety pin on the master dispenser itself). You could (and people did)
accidentally fire them on the ground. There was *no* direct tie between
the ALE-40 and the rest of the active systems on the plane, the
dispenser control panel just went straight to the ALE-40 (although a mod
to allow the ALR-69 to fire the chaff was possible, we didn't have
that).

When we did tests of the system, we just slapped a power unit on the
plane, fired everything up, turned the ALE-40 on, and used a tester to
see if the individual cart pins were getting firing voltages (through
the high-tech method of looking at a bunch of light bulbs on a box and
counting them as they lit when we pressed the button).

--
cirby at cfl.rr.com

Remember: Objects in rearview mirror may be hallucinations.
Slam on brakes accordingly.