AIM-152 AAAM Phoenix replacement projects

Yes my post got moved here from the thread on the ATA/A-12 since it dealt more with the AIM-152 but I had forgotten about that possibility of data-linked engagements.

It does provide an interesting secondary use for such attack aircraft to put them on patrol if the CVBG was in a situation where there was nothing within striking distance.
And they have a loiter time at least as long as the Tomcats, just as a function of range divided by speed...
 
I don’t understand why GDW wanted to use SARH when they could have used datalink to send periodic updates and have terminal IR/EO guidance. The rest of the missile was so damn advanced. TVC, restartable solid rocket motor, two color IR seeker, Phoenix performance in Sparrow/AMRAAM form factor and weight. SARH only makes sense when you’re fighting bombers that don’t have fighter escorts that can fire back at you, and for everything else, it’s a liability. While the radar pod concept does have its merits, it takes away a hard point and looks to be as large as or even larger than the LANTIRN pod. The F-15/16/18 could have made good use of this missile. Contrast that with the Hughes Raytheon design, which could probably be a better BVR missile because of ARH/IR terminal guidance.

Nevermind this was the actual guidance scheme my bad
 
Last edited:
SARH only makes sense when you’re fighting bombers that don’t have fighter escorts that can fire back at you, and for everything else, it’s a liability.
Also it should be obvious that an AMRAAM type guidance system would have been less of a hassle. Plus the restartable motor of the GDW with its two stages and TVC would probably have a similar probability of kill while being lighter and the launch aircraft being able to carry more of them compared to the Hughes Raytheon.
 
Active radar guidance is one of the reasons I think the Hughes design was better suited for the primary role (intercepting bombers and missile carriers) of the AAAM. Some of the features on the GD design were still highly promising, the dual-pulse solid rocket motor in particular should have been carried over to the AMRAAM program ages ago.

I know someone on this board had explained the rationale of missiles being carried and launched from a canister as the GD design was, but I am having trouble finding that post. I know many other missile prototypes were tested in canister-launched configurations, including the AIM-95.
 
Reading back through this thread, I'm not sure if SARH is a totally accurate description of the GD missile's guidance mode.

For example:

A General Dynamics official said his team's AAAM will use a pulsed radar that will cue the missile and tell it when the next pulse and data burst will be. The information is coded, and will be pulsed at many times per second in the terminal phase, on a different frequency each pulse to survive ECM. The missile is updated through the targeting pod, which can talk to the missile and track targets from the front or back, making it a "launch and maneuver" weapon, the company official said. In terminal phase, the radar radome is jettisoned to expose a hemispherical IR seeker.

That sounds much more like the AEGIS midcourse guidance scheme, where the missile gets guidance cues from the external radar, which in this case is essentially doubling as an in-band datalink. Each pulse seems to function as both an monopulse illumination signal and a tracking data update. In this case, the quasi-SARH guidance may be significantly more ECM-proof, because it can change signal characteristics pulse to pulse, and is giving the missile a target location update even if the actual return form the target is swamped by jamming.
 
I know someone on this board had explained the rationale of missiles being carried and launched from a canister as the GD design was, but I am having trouble finding that post. I know many other missile prototypes were tested in canister-launched configurations, including the AIM-95.
Better reliability, potentially reduced drag and RCS?
 
The Zaslon radar was able to support 4 R-33s against widely separated targets using semi-active homing at once. With 1970s Soviet technology passive phased array. Using a phased array was the key though, a mechanically scanned planar array would not be able to illuminate many targets at once. AWG-9 could get Phoenix to terminal seeker range, but it needed its own radar to complete the engagement.

I found this Chinese translation of a paper on APG-79. Makes an interesting claim that it was designed for both the Super Hornet AND the Tomcat.
 
That sounds much more like the AEGIS midcourse guidance scheme, where the missile gets guidance cues from the external radar, which in this case is essentially doubling as an in-band datalink. Each pulse seems to function as both an monopulse illumination signal and a tracking data update. In this case, the quasi-SARH guidance may be significantly more ECM-proof, because it can change signal characteristics pulse to pulse, and is giving the missile a target location update even if the actual return form the target is swamped by jamming.
But does it really need the radar seeker then except for aerodynamics when you can just give the missile updates on the target via a rear facing receiver? Sorry if I'm being stupid.
 
I think you are exactly correct that the guidance system is modelled on the Aegis / Standard SM-2. Don't forget Standard was also a Convair (General Dynamics) Pomona product.

Combining rear and front antennas makes sense for various reasons. The front seeker can use monopulse to measure accurate single-pulse range and direction for starters. SARH "fixes" will be more accurate than INS + updates from a distant host aircraft. The host aircraft is moving, the target is moving, the missile is moving... some hard maths involved. SARH signal is much simpler and accurate - target is this way, moving in this direction.
 
But does it really need the radar seeker then except for aerodynamics when you can just give the missile updates on the target via a rear facing receiver? Sorry if I'm being stupid.
It sounds like they were using both for redundancy. "Launcher says target is here, missile seeker agrees. Launcher says target is here, missile seeker is jammed. Launcher says target is here, missile seeker says it's over here, splitting the difference."

Remember, this was intended to be going after the Naval Aviation Tu16s and Tu22Ms, which would be packing some of the heaviest jammer capabilities outside of a dedicated craft like an EA6B. Able to pump out enough static to black out New York City.

Edited to correct aircraft types.
 
Last edited:
It sounds like they were using both for redundancy. "Launcher says target is here, missile seeker agrees. Launcher says target is here, missile seeker is jammed. Launcher says target is here, missile seeker says it's over here, splitting the difference."

Remember, this was intended to be going after the Naval Aviation Tu160s, which would be packing some of the heaviest jammer capabilities outside of a dedicated craft like an EA6B. Able to pump out enough static to black out New York City.
In that context, it does make sense. Thanks for explaining.

Edit: could an IR seeker in the terminal guidance phase circumvent said jamming entirely?
 
Last edited:
Edit: could an IR seeker in the terminal guidance phase circumvent said jamming entirely?
Still would have to deal with flares and any decoys (equivalent to ADM-20 Quail) they might field, and IIRC they'd pop both chaff and flares at the same time.

Nothing is countermeasure proof. Just more or less resistant.
 
In that context, it does make sense. Thanks for explaining.

Edit: could an IR seeker in the terminal guidance phase circumvent said jamming entirely?
I guess it should be expected the Tu-160/22M would drop flares and chaff like there is no tomorrow, but having additional seeker would still help to solve some of the issues
 
Remember, this was intended to be going after the Naval Aviation Tu16s and Tu22Ms, which would be packing some of the heaviest jammer capabilities outside of a dedicated craft like an EA6B. Able to pump out enough static to black out New York City.
Even then, there were dedicated ECM squadrons in Soviet Naval Aviation. A full divisional-strength attack on a carrier group would be very demanding.
I guess it should be expected the Tu-160/22M would drop flares and chaff like there is no tomorrow, but having additional seeker would still help to solve some of the issues
Dual seekers force the enemy to deploy much more sophisticated countermeasures. Modern guidance logic is quite capable of discerning that the target did not (a) suddenly stop and massively increase its RCS, or (b) decide to make a 1g dive, making simple chaff and flares ineffective. There's a reason towed decoys have become a thing!
 
It would not fit into the F-22's bay, apparently, although word is it would fit into the F-23's
How so? The GDW design had an 8 inch maximum diameter, and the fins were just 5.5 inches, so the maximum diameter with fins included equals 11 inches, compared to the AIM-120Cs 7 inch body plus 18 inch fins (26 in max diameter). The AMRAAM-C is also 3660 mm long, compared to the planned length of 3607 mm for the GDW AAAM. So I don’t see how it would not fit into the bay. Or were you talking about the Hughes/Raytheon design?

Sources




AAAM.png
 
Last edited:
How so? The GDW design had an 8 inch maximum diameter, and the fins were just 5.5 inches, so the maximum diameter with fins included equals 11 inches, compared to the AIM-120Cs 7 inch body plus 18 inch fins (26 in max diameter). The AMRAAM-C is also 3660 mm long, compared to the planned length of 3607 mm for the GDW AAAM. So I don’t see how it would not fit into the bay. Or were you talking about the Hughes/Raytheon design?

Sources




View attachment 727668
Fins were folding.

AIM-152cc.jpg

 
IMO it was extremely shortsighted that the AAAM was cancelled and no official in the USN and DoD are deeply regretting that decision. However the project could be resurrected by being based on the AMRAAM.
 
IMO it was extremely shortsighted that the AAAM was cancelled and no official in the USN and DoD are deeply regretting that decision. However the project could be resurrected by being based on the AMRAAM.
It was, but the Soviet Union imploded so fast that I think everyone was kinda stunned.

If the USSR had stuck around as a larger entity for longer (late 1990s or early 2000s), I suspect that the AAAM would have been developed. Which may have lead to upgraded radars for F15s and maybe F22s to carry the beasts as well. I think the GDW design would likely have taken the competition, it's really hard to beat 12-15 long range missiles per Tomcat!
 
It was, but the Soviet Union imploded so fast that I think everyone was kinda stunned.

If the USSR had stuck around as a larger entity for longer (late 1990s or early 2000s), I suspect that the AAAM would have been developed. Which may have lead to upgraded radars for F15s and maybe F22s to carry the beasts as well. I think the GDW design would likely have taken the competition, it's really hard to beat 12-15 long range missiles per Tomcat!
If the USSR had stuck around longer, the AAAM would probably have prototypes built and tested. The rapid collapse of the USSR in our timeline caused the whole “Peace Dividend” tornado, which swept up a lot of forward thinking defense projects (AAAM) or stalled existing ones like the B-2/ATF.

Anyway, in my opinion, the choice could be either one. The HR design offered proven propulsion methods (ramjet) and relative simplicity, while the GDW design offered significantly more advantageous form factor (as small as a sparrow without fins), and could be the base for a significant leapfrog in AAM technology with its thrust vectoring and dual pulse motor.

I personally prefer the GDW design, because the form factor could have made it compatible with a lot more platforms, especially those with internal bays and in larger numbers. The AMRAAM was a good missile when introduced, but it was not really a BVR capable missile in the A and B versions. It also relies on coasting to its target at longer range, whereas the GDW AAAM had that second stage that would start near the target for maximum energy and low escape chance. IR terminal homing also would not set off the targets RWR, so there was less warning compared to terminal radar homing. The front end of a GDW missile could also be a dogfight missile if the radar seeker was removed, or if desired, could function as a long range IR missile similar to the R-27T/ET.
 
Correct me if im wrong, because the whole post is based upon the assumption that it is possible for ramjets to be restarted in flight.

Could you increase the range of the Hughes/Raytheon missile by changing the flight profile to this:

Launch: the missile accelerates to Mach 1, ignites its ramjet, and accelerates to top speed (Mach 3.5 to 4?), then coasts until it reaches Mach 2/2.5 reignites the ramjet and accelerates back to top speed. Repeat until it reaches the target or runs out of fuel.
 
Correct me if im wrong, because the whole post is based upon the assumption that it is possible for ramjets to be restarted in flight.

Could you increase the range of the Hughes/Raytheon missile by changing the flight profile to this:

Launch: the missile accelerates to Mach 1, ignites its ramjet, and accelerates to top speed (Mach 3.5 to 4?), then coasts until it reaches Mach 2/2.5 reignites the ramjet and accelerates back to top speed. Repeat until it reaches the target or runs out of fuel.

One problem is that the ramjet doesn't do the accelerating. It's an integral ram-rocket, so there's a solid motor in the combustion chamber that has to burn up before the ramjet can operate. The solid rocket motor takes the missile from launch to max velocity. The ramjet is effectively a sustainer motor. You could presumably throttle it down at mid-course but I'm not sure you'd gain much.
 
Correct me if im wrong, because the whole post is based upon the assumption that it is possible for ramjets to be restarted in flight.

Could you increase the range of the Hughes/Raytheon missile by changing the flight profile to this:

Launch: the missile accelerates to Mach 1, ignites its ramjet, and accelerates to top speed (Mach 3.5 to 4?), then coasts until it reaches Mach 2/2.5 reignites the ramjet and accelerates back to top speed. Repeat until it reaches the target or runs out of fuel.
Ramjets can be restarted in flight. Apparently the RJ43 in the D-21 would flameout in turns at times but then would relight when it straightened out. Don't know if they had to do something special to make it happen or if the engine interior was still so hot that when conditions were right it spontaneously reignited.

071025-F-1234S-009.jpg
 
One problem is that the ramjet doesn't do the accelerating. It's an integral ram-rocket, so there's a solid motor in the combustion chamber that has to burn up before the ramjet can operate. The solid rocket motor takes the missile from launch to max velocity. The ramjet is effectively a sustainer motor. You could presumably throttle it down at mid-course but I'm not sure you'd gain much.
What I meant was that you get the missile up to max velocity, let it coast, (re)ignite the ramjet to get it back to max velocity, coast, repeat.
 
Two things really stood out to me on the GDW design.

1. The Illuminator pods radars, despite being clearly some sort of phased array, most likely PESA, still had mechanical steering up to seemingly 30± degrees horizontal and vertical . This indicates to me that the Pod was designed with Notching/Beaming in mind for cases in which the target aircraft was capable of fighting back or had escorts that could fire at the launch aircraft. It also seems to be of similar size to the LANTIRN pod.

2. This picture shows the internals of the proposed missile along with a bunch of photos of parts of the missile, clearly indicating that GDW had already built some of the technology planned for the missile. I don’t know if i am being naive here about the authenticity of the pictures, but it seems real to me. GDW seems to have proposed a system that while offering a lot of capability, has the real world demonstrations to back its claims up.
 

Attachments

  • ATI 2.jpg
    ATI 2.jpg
    655.2 KB · Views: 49
  • AIM-152b 2.jpg
    AIM-152b 2.jpg
    231.1 KB · Views: 49
Two things really stood out to me on the GDW design.

1. The Illuminator pods radars, despite being clearly some sort of phased array, most likely PESA, still had mechanical steering up to seemingly 30± degrees horizontal and vertical . This indicates to me that the Pod was designed with Notching/Beaming in mind for cases in which the target aircraft was capable of fighting back or had escorts that could fire at the launch aircraft. It also seems to be of similar size to the LANTIRN pod.
Most likely both arrays could steer to achieve omnidirectional targeting-I'd expect a decent size Backfire/Oscar attack to have some "slippers" that manage to get past the first kill wave. So combining both mechanical steering and dual hemisphere arrays you have more allowance in intercept geometries.
2. This picture shows the internals of the proposed missile along with a bunch of photos of parts of the missile, clearly indicating that GDW had already built some of the technology planned for the missile. I don’t know if i am being naive here about the authenticity of the pictures, but it seems real to me. GDW seems to have proposed a system that while offering a lot of capability, has the real world demonstrations to back its claims up.
Both of the contracted teams did. At the very least the HR design is probably more matured and technologically feasible. The larger form factor could also means greater growth margins.
 
Most likely both arrays could steer to achieve omnidirectional targeting-I'd expect a decent size Backfire/Oscar attack to have some "slippers" that manage to get past the first kill wave. So combining both mechanical steering and dual hemisphere arrays you have more allowance in intercept geometries.

Both of the contracted teams did. At the very least the HR design is probably more matured and technologically feasible. The larger form factor could also means greater growth margins.
Omnidirectional targeting would only work to one side though, unless you find a way to carry the pod under the engine nacelle, or in the space between the engines on an F-14.

I really want to see the tech validation the HR team did. With growth opportunity, it's probably true. The only way to increase range on the GDW design would be to increase the diameter of the second stage.
 
2. This picture shows the internals of the proposed missile along with a bunch of photos of parts of the missile, clearly indicating that GDW had already built some of the technology planned for the missile. I don’t know if i am being naive here about the authenticity of the pictures, but it seems real to me. GDW seems to have proposed a system that while offering a lot of capability, has the real world demonstrations to back its claims up.

As far as I know both teams got as far as ground tests of test articles (Including rocket-motors) before the programme was cancelled, I suspect that if the Cold War had lasted a year longer we'd have seen flight-tests of XAIM-152A prototypes.
 

Similar threads

Please donate to support the forum.

Back
Top Bottom