Advanced US short-range AAMS for the 1970s - AIM-82, AIM-95 Agile, CLAW

[overscan (PaulMM)]

AIM-95 Agile started out in 1968 as a project of the Naval Weapons Centre, China Lake to explore new technologies for short range, manouvreable AAMs. The US Navy requirement asked for greater agility, shorter minimum range, and greater off-boresight capability. Under the "QuickTurn" program, in 1970 a China Lake test TVC (thrust vectoring control) system demonstrated 55g turns and 118 deg AOA (angle of attack) capability. The USAF AIM-82 project was shelved due to the progress of the Agile program.

In 1973 Hughes were given responsibility for guidance, and Thiokol the propulsion system. The principal guidance system was to be IR, but an EO seeker was also tested and an passive radar seeker was planned. Millions of simulated firings were made, and missiles and seekers were tested, but the program was cancelled in 1975 on cost grounds.

Sources

• R. T. Pretty & D. H. Archer, Jane's Weapons Systems 1974-75 p147
• Bill Gunston, Illustrated Encyclopaedia of the Worlds Rockets & Missiles Salamander 1979, p231
• https://web.archive.org/web/20090315114221/http://airpower.callihan.cc/HTML/mrb.htm

 

[overscan (PaulMM)]

Here is the only possible picture of AIM-82 I've found

Source: Aerofax F-15 and Warbirdtech F-15, both by Dennis R Jenkins

[image later removed - Overscan]

 

[elmayerle]

Here's the AIM-95 entry in my favorite online missile database:

Hughes AIM-95 Agile

And the AIM-82 entry:

AIM-82

 

[overscan (PaulMM)]

The webmaster, Andreas Parsch, visits this forum from time to time.

 

[Andreas Parsch]

The webmaster, Andreas Partsch, visits this forum from time to time.

Indeed .

I assume that in your picture the small missiles carried in tandem in front of the Sparrows are supposed to be AIM-82s. Is this just a "notional design", or does it show a specific design submitted by one of the AIM-82 study contractors?

 

[overscan (PaulMM)]

I'm not sure. The image is obviously the winning F-15 proposal with ventral fins, etc, which places it in the right timeframe, and is an image I've seen before, but I didn't spot the IR missiles myself- Dennis R Jenkins specifically calls it AIM-82 in his WarbirdTech F-15 book. I don't know on what authority, and he certainly doesn't say whose AIM-82 proposal it might represent. It must be quite a small missile, though I haven't yet tried scaling it from the AIM-7; its a little like an R-60 (AA-8 APHID) without the fixed fins in front of the canards.

 

[sferrin]

I'm not sure. The image is obviously the winning F-15 proposal with ventral fins, etc, which places it in the right timeframe, and is an image I've seen before, but I didn't spot the IR missiles myself- Dennis R Jenkins specifically calls it AIM-82 in his WarbirdTech F-15 book. I don't know on what authority, and he certainly doesn't say whose AIM-82 proposal it might represent. It must be quite a small missile, though I haven't yet tried scaling it from the AIM-7; its a little like an R-60 (AA-8 APHID) without the fixed fins in front of the canards.

I also recall reading a book back in the 80s on the F-15 in which this same photo was used and they also captioned that it was an AIM-82.

 

[overscan (PaulMM)]

Another picture of Agile.

According to Friedman, Agile was cancelled in 1975 as it was "judged overexpensive and technically immature".

Source:

• Norman Friedman, The Naval Institute Guide to World Naval Weapons Systems, 1989

 

[overscan (PaulMM)]

AIM-82 was studied from 1969. Definition contracts were awarded to Hughes, Ford and General Dynamics (Pomona) in July 1970. It was cancelled in September 1970, as improved Sidewinders were thought to give similar results, and the Agile program became officially a joint services project.

The USAF studied another missile called CLAW (CLose-range Attack Weapon), a "low cost weapon about quarter of the weight of Agile".

The Agile seems to have been substantially heavier than the Sidewinder.

Source:

• Norman Friedman, The Naval Institute Guide to World Naval Weapons Systems, 1989

 

[overscan (PaulMM)]

Agile/QuickTurn (QT) The 8-inch-diameter QT system was a highly maneuverable, short-range air-to air missile that had a fast-response, 15-degree omni axis capability gimbal ring/ball-in-socket nozzle TVC system, which was supplied by Thiokol Corp., Wasatch Division.
NWC provided the control system and integrated the rocket motor TVC system into the complete missile assembly.

After highly successful flight demonstrations, including controlled angles of attack greater than 90 degrees, the complete propulsion system was transitioned to Thiokol Corp. for the Agile portion of the program. Tactical planners questioned the need for development of a highly maneuverable, short-range, air-to-air missile; some technical problems arose during development of the advanced, high-off-boresight-capability seeker, and the program was canceled.

J. M. Robbins & R. W. Feist AIAA article 92-3612 The China Lake Propulsion Laboratories

The AIM-95A (Agile) is a short-range air-to-air missile with high-angle thrust vector control (TVC) and is currently in the engineering development phase. The system envelope is approximately 8 inches in diameter by 100 inches long. Thc propulsion/steering system is comprised of a solid-propellant boost-sustain rocket motor, an omniaxis gimbal nozzle with a 20-degree gimbal angle, and a “warm gas” generator to pressurize the nozzle actuating hydraulic system.

AGILE Gimbal Nozzle Mechanics Investigation AIAA article 73-1205

 

[overscan (PaulMM)]

Agile is mentioned in the following Aviation Week issues if someone has access via a library etc.

Vol 92, p. 19, Mar. 2, 1970
Vol 99, p. 51, July 23, 1973

 

[overscan (PaulMM)]

From chinalakealumni.org

 

[overscan (PaulMM)]

Interesting size comparison

 

[TinWing]

Agile/QuickTurn (QT) The 8-inch-diameter QT system....

So now we know that Agile had a diameter of at least 8 inches (203mm)! This is a great find, and the first dimension data I have ever seen for this program.

 

[sferrin]

I wonder how well it would do today with the seeker of an AIM-9X. At 8" diameter it should have had a lot of impulse.

 

[overscan (PaulMM)]

The system envelope is approximately 8 inches in diameter by 100 inches long

Thats 203mm diameter, 2.54m length. Looks correct from the picture comparing to Sidewinder & Sparrow - shorter than Sidewinder but as fat as Sparrow.

 

[overscan (PaulMM)]

Flying Review, March 1969, mentions a close range missile called "Dog Fighter" similar to the UK Tail Dog project. $90m was sought in the 1969 budget but not approved. AIM-82?

 

[overscan (PaulMM)]

Confirmed.

AIM-82 "Dog Fighter"
Highly manouverable missile (to substitute for 20mm cannon)
Feasibility study only
300m-3.2km range
IR or Optical homing
Similar to Navy "Quick Turn" program

Flying Review International Nov 1969

 

[overscan (PaulMM)]

Flying Review March 1968

Dog Fighter
TV and all aspect IR guidance considered
Preliminary design on project (RAD-225) performed by Raytheon on the basis of a "short range Sparrow"
Recent effort focussed on growth version of AIM-4D Falcon

 

[SOC]

That Falcon growth version was the XAIM-4H. It was to have been configured for fighter v fighter combat including dogfighting, and would have featured a proximity fuze, among other improvements.

 

[overscan (PaulMM)]

Thc AIM-95A (Agile) is a short-range air-to-air missile with high-angle thrust vector control (TVC) and is currently in the
engineering development phase. The system envelope is approximately 8 inches in diameter by 100 inches long. The propulsion/
steering system is comprised of a solid-propellant boost-sustain rocket motor, an omniaxis gimbal nozzle with a 20-degree gimbal
angle, and a “warm gas” generator to pressurize the nozzle actuating hydraulic system.

Source:

AGILE Gimbal Nozzle Mechanics Investigation AIAA article 73-1205

 

[overscan (PaulMM)]

According to Davies & Thornborough AIM-82 Dogfighter contracts were issued to General Dynamics, Philco-Ford and Hughes to design and build a prototype. It was cancelled after 5 months of "extravagant claims" and "heated unarmed combat between manufacturers, politicians and cost analysts".

Source:

Peter E. Davies & Anthony Thornborough, McDonnell-Douglas F-15 Eagle (Crowood, 2001)

 

[overscan (PaulMM)]

http://www.chinalakealumni.org/1972/1972.htm
http://www.chinalakealumni.org/1972/1971.htm
http://www.chinalakealumni.org/1972/1970.htm

 

[overscan (PaulMM)]

http://www.marvellouswings.com/Aircraft/Missile/M-095/M-095.html

 

[sferrin]

Look at the FOV behind the two guys on the picture. It's huge.

 

[pathology_doc]

According to Bill Gunstron LCLM was a Ford proposal within the ASRAAM program

Source:

Bill Gunston, The Illustrated Encyclopaedia of the World's Rockets and Missiles

Heh. IIRC Gunston also quoted the Vickers Red Dean as having about ten times the useful range it actually possessed, so I'm inclined to take anything on cancelled or paper projects from that source with a pinch of salt. That's not to say he isn't right, or wasn't writing reliably from what was known at the time, but much of what is known now seems to march well beyond the books of that era.

 

[overscan (PaulMM)]

Bill Gunston had no actual hard facts on Red Dean / Red Hebe when writing the book and was merely extrapolating from e.g. US missile designs. If you didn't know Red Dean was "engineering archaeology" even in the 50s you might wonder why its range was so pitiful.

 

[Abraham Gubler]

At this time one of the biggest limitations on semi active radar homing missiles was the power of the illuminator. The illuminator’s effective range was dependent on reflecting enough radiation from the target right back to the launcher so the missile seeker could begin homing right from launch. Since the missiles only flight control system was provided by the seeker without a sniff of radiation it would just fly off out of control if launched. The development of missile auto pilots that could fly to an interception point without seeker guidance meant that range for the same seeker could be almost doubled as the illuminator’s radiation would only need to reflect back a much smaller distance from the target to enable the seeker to home in (not to mention more efficent flight paths thanks to the auto pilot). Which is why from a target illumination perspective beam riding makes a lot more sense as all things being equal it needs much less radar power. So you could have a rocket motor able to power the missile out to 100 miles but if the seeker can only pick up the illuminator reflecting back from the target at 20 miles that is you maximum range.

 

[Sea Skimmer]

And the downside of radar beam riding guidance is accuracy decreases steadily with range, and is still dependent on the transmitter antenna design and size to make a sufficiently narrow beam to have any useful accuracy at all. End result is unless you have a nuclear warhead any range advantage gained over a comparable semi active system is likely to be useless against more then a target drone, and maybe not even that. However it will make for a much cheaper and simpler missile, which was the main reason to use it on early AAM projects, as well as some later point defense SAMs.

 

[sferrin]

Did any use a combination of beam riding and SARH to get around the limitations of both?

 

[Sea Skimmer]

I've never heard of it, it would be an awful lot of trouble for very marginal gains. Among other things it would be difficult to project a beam suitable for both semi active and beam riding guidance at the same time, which means either two transmitters, or switching over modes in mid flight, which sounds to me like a good way to make the missile fail.


Meanwhile illuminator technology improved very rapidly and soon outpaced the performance the rocket motors could provide anyway. Beam riders were for the most part only emergency weapons, Sparrow 1 for example only had about 2,000 missiles produced. Outpacing rocket motor performance what made mid course command guidance and autopilots attractive in much later 70s era SARH AAMs and SAMs, because they could allow the missile to preserve some of its energy by not following very last twitch the target aircraft made, until it mattered. Beam riding could never do this. Beam riding is the total opposite, it makes the missile waste massive amounts of energy as it swings from one edge of the beam to another constantly. That's why most beam riding air to air missiles missiles only had a rated range of 4-6nm or even worse such as the Soviet K-5 which only went about 3nm, though it was also rather small. These weapons all had the pure speed to go further, but it was massively wasted bouncing around. The rare longer ranged beam riders, such as Sea Slug, had large sustainer motors to keep them going, and took advantage of large naval or ground radars to generate narrower beams then was possible from a fighter set.

 

[chuck4]

Wonder if anyone thought about laser beam riding for AAM. One could create a much tighter beam with same aperture using laser than using RF.

 

[SpudmanWP]

A beam rider (like StarStreak) is different than laser spot tracker (like Hellfire).

A beam rider has to travel in a straight line but cannot be jammed while a spot tracker can fly in intercept profile but can be jammed with DIRCM.

 

[chuck4]

A beam rider (like StarStreak) is different than laser spot tracker (like Hellfire).

A beam rider has to travel in a straight line but cannot be jammed while a spot tracker can fly in intercept profile but can be jammed with DIRCM.

I actually mean laser beam riding, a missile traveling inside a very narrow, conical laser beam, and steering itself by detecting the edge of the beam. Since the laser receivers points at the launch aircraft, it would be impossible for a target to jam.

I believe Russians use this mode of guidance for short range surface to air missile.

 

[Yellow Palace]

Did any use a combination of beam riding and SARH to get around the limitations of both?

Talos apparently did - of course, it had an entire cruiser to support its' trackers, and the missile wasn't much smaller than some fighters.

 

[sferrin]

Did any use a combination of beam riding and SARH to get around the limitations of both?

Talos apparently did - of course, it had an entire cruiser to support its' trackers, and the missile wasn't much smaller than some fighters.

Pretty sure with Talos it was either/or not both. The nukes were beam riders with the conventional Talos being SARH.

 

[SpudmanWP]

I actually mean laser beam riding, a missile traveling inside a very narrow, conical laser beam, and steering itself by detecting the edge of the beam. Since the laser receivers points at the launch aircraft, it would be impossible for a target to jam.

This is how StarStreak works.

The problem of having a BR AAM is that to get the best range out of a AAM it needs to fly an intercept course. This is not possible with a BR since the laser beam could not move quick enough to compensate for rapid movements of the target aircraft.

Besides, between GPS based updates, HOJ, and a solid datalink, an AAM should have little problem locking onto a target.

 

[TomS]

Pretty sure with Talos it was either/or not both. The nukes were beam riders with the conventional Talos being SARH.

I think it actually was both -- most descriptions of conventional Talos talk about the SARH terminal guidance coming on late in the engagement, with beam riding being used to put the missile close enough to the target for terminal guidance. That's how Talos could do things like attack from above, if the operator steered it over the target before going to terminal homing. For example:

http://www.astronautix.com/lvs/talos.htm


Edit: OK, even better description here:

Talos Missile Guidance and Homing History

Very interesting reading. The beam-riding phase used some very neat tricks to keep the missile from snaking around as much as it might.

 

[chuck4]

I actually mean laser beam riding, a missile traveling inside a very narrow, conical laser beam, and steering itself by detecting the edge of the beam. Since the laser receivers points at the launch aircraft, it would be impossible for a target to jam.

This is how StarStreak works.

The problem of having a BR AAM is that to get the best range out of a AAM it needs to fly an intercept course. This is not possible with a BR since the laser beam could not move quick enough to compensate for rapid movements of the target aircraft.

Besides, between GPS based updates, HOJ, and a solid datalink, an AAM should have little problem locking onto a target.

If the laser beam is steered by some high pixel optical or IR sensor, then it should be able to respond very quickly to target movement. Since the laser beam riding guidance is in effect a command guidance system with much of processing done onboard the launch aircraft instead of onboard the missile, it should be possible to point the beam not always directly at the target, but in a direction that would move the missile toward the target along an efficient intercept course.

With spherical coverage distribute aperture optical sensor of the type on the F-35, there ought to be the basis for a spherical coverage, optically searched and tracked, laser based beam-riding/command guidance based guidance system for short range missiles.

 

[SpudmanWP]

For beam guidance to work, the beam can only move as fast as the missile is capable of moving. If you move the laser too quickly the missile will lose track of it. This means that not only will the fighter have to track the enemy, but also his own missile. He will also need to be able to project the laser all around the aircraft unless he is willing to fly straight at the enemy.

Then there is the issue of only being able to fire one missile at a time (unless he has multiple laser projectors).

It's just not feasible or practical.