AMRAAM question

[Emu]

An AMRAAM can be used LOBL but can it be cued via HMCS in LOBL use? Can the seeker be cued via HMCS in addition to this? Can the seeker perform the search itself?

Edited April 16, 2019 by Emu

[SFJackBauer]

I've never seen anything that would indicate that this would be possible.

 

As far as I understand active radar-guided missiles tend to stay shut-off until launched, unlike passive seekers. The aircraft has a bigger radar anyways, so why use the missile as seeker, instead of conserving it (in terms of battery and cooling) until it is actually needed?

 

I am referring to the "seeker perform the search itself".

 

As for LOBL, when launched at short range, the seeker goes active off the rails. It must immediately acquire the target, therefore it has to be within its FOV. Given that it has 30° field of regard, it means pretty much pointing the nose at it.

 

AIM-9X has 90° seeker field of regard.

Edited April 17, 2019 by SFJackBauer

[GGTharos]

There is no LOBL with AMRAAM as far as I know. The seeker never comes online on the rail. The earliest will be right after launch, and it will then perform a search based on whatever data was uploaded to the missile before launch

 

The AMRAAM had no less than 50 degree seeker gimbals - I don't recall the exact number. 30 degree gimbals are silly and over half a century out of date.

[Emu]

There is no LOBL with AMRAAM as far as I know. The seeker never comes online on the rail. The earliest will be right after launch, and it will then perform a search based on whatever data was uploaded to the missile before launch

 

The AMRAAM had no less than 50 degree seeker gimbals - I don't recall the exact number. 30 degree gimbals are silly and over half a century out of date.

Is that +/-50deg or +/-25deg?

[GGTharos]

+/- 50 degrees.

[Schmidtfire]

What about HOBS functionality? Should the Aim-120B/C be able to do that or is that

for Aim-120D only?

[GGTharos]

I don't know, nor do I know what 'HOBS' means in this case for the AMRAAM. AMRAAM would have no problem turning all around for 180 degrees technically - if you think about it, what it needs is a way-point to fly to to activate its seeker, and target parameters. Is this practical? I don't know.

[Schmidtfire]

HOBS = High-Angle Off-Boresight

 

Just found out that it was introduced with the AIM-120D.

Edited April 17, 2019 by Schmidtfire

[GGTharos]

I know what HOBS is. I don't know what it means for the AMRAAM. For the AIM-9X it's obvious ... for the AIM-120, not so obvious - ie. the exact workings of what the missile is doing are unknown.

[Emu]

With HOBS (AIM-120D) can it be cued via HMCS? Presumably this will only work at reasonably long (non-dogfight) ranges though.

[GGTharos]

That is the idea. As to what it may or may not work with, who knows? HOBS capability may come with earlier fuze activation and different maneuver programming.