Can the AIM-120A/B fit inside the F-22 weapon bay?

[disconnectedradical]

This is something that I’m trying to figure out, the way AIM-120C/D is packed in the F-22 bay seems to have little room especially vertically. Even though it was said that F-22 can carry 4 AIM-120A/B or 6 AIM-120C/D, I’m not sure if there’s actually room inside to fit the A/B’s larger tailspan? The A/B tail is 25” across while C/D is 17.6” across, so the difference is pretty significant. While AIM-120A/B won’t be carried, I’m trying to see the feasibility of what can fit inside an F-22 weapon bay that bay be bigger than an AMRAAM, which is why I’m curious about whether a 25” tailspan can be fitted.

[charlielima223]

This is something that I’m trying to figure out, the way AIM-120C/D is packed in the F-22 bay seems to have little room especially vertically. Even though it was said that F-22 can carry 4 AIM-120A/B or 6 AIM-120C/D, I’m not sure if there’s actually room inside to fit the A/B’s larger tailspan? The A/B tail is 25” across while C/D is 17.6” across, so the difference is pretty significant. While AIM-120A/B won’t be carried, I’m trying to see the feasibility of what can fit inside an F-22 weapon bay that bay be bigger than an AMRAAM, which is why I’m curious about whether a 25” tailspan can be fitted.

If I remember way back in the 90s playing those Janes flight sims the YF-22 was said to carry 4-6 amraams in the bay. That was before the F-22 EMD came out and before the AIM-120C came onto the scene.

[disconnectedradical]

Well the original goal for EMD was 4 AIM-120A or 6 "compressed carriage" AIM-120C. This old graphic seems to indicate that but I don't know if it would actually fit because AIM-120A tailspan is quite a bit bigger than AIM-120C.



Looking at pictures I don't know if there's enough room for the bigger fins.

[BDF]

6 compressed carriage AMRAAMs was not a formal ATF requirement. It was looked at but deferred until after down select mainly to give AMRAAM time to stabilize production and service entry. The AMRAAM SPO didn't want to add a further variant and risk running afoul with Congress. So the compressed carriage was a desired objective and was known to both competitors but not a formal requirement.

[wrightwing]

There's no situation where an A/B version would be carried, but they probably could manage with greatly reduced carriage.

[f119doctor]

Yes, the F-22 could carry 4 AIM-120A/B in the main weapons bay. Once the C variant became available, the standard configuration is 3 missiles per side of the main bay.

[disconnectedradical]

I thought that was the original requirement but that’s surprising that it’s still possible physically because looking at pictures I’m not sure if there is enough room vertically to fit something with the AIM-120A/AB’s 25” tailspan in the bay, it looks right even with the C/D. But that might just be optical illusion. Basically I’m trying to see if the bay has the vertical room to fit a missile with a 25” fin or tail span.




During downselect the goal may have been the 4 A/B but wonder if the design was changed in light of the compressed carriage C.

[35_aoa]

My understanding is that the clipped tail -120C re-design was specifically to allow for carriage in the F-22 bays. Could be wrong on that though. Like others have said, basically irrelevant at this point.

[disconnectedradical]

My understanding is that the clipped tail -120C re-design was specifically to allow for carriage in the F-22 bays. Could be wrong on that though. Like others have said, basically irrelevant at this point.

I heard two different things, that the AIM-120C has clipped fins specifically so that AMRAAM can fit in the F-22, or that the clipped fins is meant to increase internal AMRAAM load from 4 to 6. I’m just trying to confirm if the bays are able to fit the original AIM-120A/B, that was the original requirement but the pictures of the bays make me a bit doubtful. I’m just wondering if something with a 25” span can fit into the bay, because I’ve been toying with the maximum dimensions of a missile that can fit.

[disconnectedradical]

So, from an Lockheed Martin/Boeing rendering in the mid-1990s for a documentary, it does look like the bay was designed to fit 4 of the original AIM-120A/B with the large fins. The render shows that even though only two are carried per bay, the missiles are still staggered, likely because of the large fins and tails.

https://youtu.be/g6Qh61yQgZM?t=1519

[Scorpion82]

Might well be that with a somewhat different arrangement two A/B would have been possible. Moving both outer launchers somewhat inboard should not be afoul. Remember that the YF-22 demonstrated AMRAAM firing during DEM/VAL. It might well be that the current arrangement doesn't allow two A/B per bay, due to the proximity of the outer launchers to the bay walls. A single one certainly fits on the centre station. I could imagine that the current arrangement was customised around the C model during EMD, to permit a 6 missile fit and as the C was on its way, there was no longer a need for carrying A/B.

[disconnectedradical]

Might well be that with a somewhat different arrangement two A/B would have been possible. Moving both outer launchers somewhat inboard should not be afoul. Remember that the YF-22 demonstrated AMRAAM firing during DEM/VAL. It might well be that the current arrangement doesn't allow two A/B per bay, due to the proximity of the outer launchers to the bay walls. A single one certainly fits on the centre station. I could imagine that the current arrangement was customised around the C model during EMD, to permit a 6 missile fit and as the C was on its way, there was no longer a need for carrying A/B.

I think there is some flexibility in terms of where the launcher can be mounted inside the bay. As you say, two AIM-120A/B per bay can fit if the two launchers are moved in a bit and staggered, like how that 1990s model shows it. That way it can accommodate the 25" span of the A/B, while the 19" span of C/D and the different mounting of launchers allowed 3 per bay.

This does make me wonder if the AIM-260 JATM will go for a bigger 8" diameter motor and folding fins, over the 7" diameter of the AMRAAM. Because that can give it a bigger boost, and each air-to-air station on the F-22 can handle 500 lbs, which is about how much an 8" missile would weigh.

[Scorpion82]

Now where you say it. A quadruple SDB launcher fits into the bay with an AMRAAM, if I'm not mistaken? In any case a 1000 lb GBU-32 and AMRAAM definitely fit in one bay. So there should be room for a heavier/larger AAM, and possibly still 4 AIM-120A/B, even if not needed/relevant.

[disconnectedradical]

Now where you say it. A quadruple SDB launcher fits into the bay with an AMRAAM, if I'm not mistaken? In any case a 1000 lb GBU-32 and AMRAAM definitely fit in one bay. So there should be room for a heavier/larger AAM, and possibly still 4 AIM-120A/B, even if not needed/relevant.

Yes, a quadruple SDB rack fits into a bay with an AMRAAM, and those are pretty big, 143in x 16in x 16in. One thing I think is possible is for a folding fin 1,000 lb missile to fit into the same space as 2 AMRAAMs. Doing some quick math, assuming the same length and density as an AMRAAM, you have a missile that's 11.75" in diameter, which if fitted with folding fin, should fit inside an F-22 and all F-35 variants. Essentially a long range standoff air to air missile that's the successor to the AIM-54 Phoenix and something that can target things like the KJ-500 at long range, similar to their PL-17.

Also, based on an older Lockheed drawing, it seems like the 4 AIM-120A/B load was done by staggering the missiles because of the fin span. Doing the same staggering allows 6 AIM-120C/D.