IRS-T Or ASRAAM For RSAF?

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15 years 4 months

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The RAAF competition (1998) was between the AIM-9X, ASRAAM and Python 4. The US even offered to deliver AIM-9X to the RAAF at the same time as the USAF and USN.

The AIM-9X retains the airframe, warhead, fuze and motor of the AIM-9X. The seeker is the same as the ASRAAM, and of course it adds TVC.

Python 4 lacked an imaging seeker (yes the later Python 5 has one, but Python 4 was the one on offer). They improved Python 5 performance over Python 4 due to concerns with kill times - Python 5 has increased range due to improved servos and reshaped engine thrust (high thrust, low thrust, high thrust for end game performance).

I'm fairly sure the UK is sharing ASRAAM source codes so Australia could make its own upgrades if required. The HUG Hornets have a digital interface to the missile also.

Peter thanks for clearing a few things.

Given the options available, RAAF selected the best possible Missile. No doubt AIM-9x is a makeover of ancient missile.

I'd say that in 1998 the RAAF went with the better deal. You could argue Python 5 (2005), AIM-9X (2003), AIM-9X Block II (2010?) or IRIS-T (2006) is better than the the existing ASRAAM (entered service with RAAF August 2004; RAF was mid 2002), but we are talking apples and oranges:

Agreed.

The question is which is better WVR Missile NOW for RSAF?


Is the dual imaging/mechanical IRIS-T seeker better than pure imaging IR for the others in rejecting decoys? Does IRIS-T have the ability to select target aim point, say the aircraft cockpit (I'd say yes)?

Pretty much all the missiles use a low burn off the rail, then accelerate to max speed for intercept. ASRAAM is supposed to the one of the fastest short range missiles (Mach 3.5) - what are the tradeoffs of quick turn vs fast speed (note the Python 4 was felt to be too slow)?

Am sure RSAF don't visualize soviet bombers or the imagination of jewish papers 200 Iranian flankers threat.

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15 years 6 months

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ASRAAM and IRIS-T are both maneuverable enough to hit a target behind the launch aircraft, and that's no mean feat of physics.

ASRAAM demonstrated a kill on a target more than 7 miles away. That's hardly a demonstration of a good short-range turn radius that is needed in a dogfight with HMS.
Kind of, as it stands at the moment CAMM is ASRAAM with TVC.
CAMM is ASRAAM with TVC, a datalink and I'd bet they're going to add an integrated cooler because regularly filling up missile canisters with nitrogen is definitely not a great idea.

Once they've done that, they'll basically have reinvented the MICA. Might have been a tad more cost effective to start with the MICA frame and use their own seeker...

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ASRAAM already has integrated cooling.

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Peter all trade offs with regard to greater speed and acceleration can be translated into greater cost... there is no relevant agility(axial translation) trade off with regard to making a missile kinematically superior - if anything it increases its translational envelope.

The only problem that I could see becoming a small issue is in the very very very close game - a few hundred meters and depending on the shot attempt, ie whether the opponent is crossing your jet - depending on how the missile accelerates and how it utilises Pro-Nav; you may get to a point where the missile accerlerates to quickly to a speed that doesn't allow for optimum axial translation in the early off the rail game. So I suppose it depends on how controllable the acceleration is - how effective its Pro-Nav is - and only would be a problem in the very very close in crossing shots. Beyond that the greater KE should afford the ASRAAM some of the best axial translation in the business - a vital quality for nailing the high speed interceptors like a Mig-23/F-22 supercruiser or Mig-25 that might not go slow - meaning AIM-9 envelopes shrink to a few miles.

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Two other ASRAAM snippets (both from JALW):

"It is wingless, with clipped delta tail control surfaces and lifting body aerodynamics with relaxed stability for high manoeuvrability."

"The BAE Systems Royal Ordnance Defence solid propellant rocket motor uses a steel strip laminate case and has a boost/sustain thrust profile with low IR signature and low flame plume."

Relaxed stability is what modern fighters use for high agility. I have 50G for the ASRAAM, but I'm unsure of the source for this. Its not a slouch against AIM-9X or IRIS-T in other words.

The second quote almost sounds like the motor is looking to reduce MAWS detection ranges...

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swerve, Did you take it literally!! C'mon be a sport.;)

Now can we move on with which is better WVR Missile for RSAF??


I'll gladly stick to the topic. You're the one who introduced irrelevancies & factual errors. Do you mean by this that you will now begin to discuss this matter seriously?

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ASRAAM demonstrated a kill on a target more than 7 miles away. That's hardly a demonstration of a good short-range turn radius that is needed in a dogfight with HMS......

Are you saying that agility & a range of over 7 miles are mutually exclusive? Why?

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15 years 4 months

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I'll gladly stick to the topic. You're the one who introduced irrelevancies & factual errors. Do you mean by this that you will now begin to discuss this matter seriously?

Yes swerve, I do want to discuss seriously, but the comments like these won't help;


If it pulls over 30 gs, it's "perfectly fine"


The ASRAAM would be a good pick because of its capability to pull high G forces, against maneuvering Iranian aircraft.


it was designed with Britain's needs and dogfighting experience in mind (something Germany hasn't had since it the Battle of Britain...which it lost :P)

Apart form all the spin that is spewed here, you know that ASRAAM was designed to engage soviet bombers over extended range with ripple fire of asraam without merge, knowing very well agility of the tornados.

ASRAAM as you can see, hardly has any control surfaces nor the TVC to help it engage the target second time, which most Missile nowadays expected off. But instead what we hear from faithfuls is the good seeker, ECCM, algorithm Blah Blah.. Mumbos, as if these are found only in ASRAAM:eek:

I seriously hope RSAF select IRIS-T, but then again looking at the defence acquisition here, it is doubtful.

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15 years 6 months

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ASRAAM already has integrated cooling.

This goes directly against MBDA own brochures:

Cooling system

Accepts argon, nitrogen or air supplies

Every single source I've seen state the the ASRAAM (and IRIS-T) seeker uses a classic Joule-Thomson cooler.

Are you saying that agility & a range of over 7 miles are mutually exclusive?
Not at all. I'm simply pointing that intercept at such a large distance is not a proof of a good turning radius.

Physics tell us that even with a 50g acceleration the missile turn radius will still be quite large (>1 km), at close ranges missiles with TVC (IRIS-T, AIM-9X or MICA) will have the advantage.

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Not at all. I'm simply pointing that intercept at such a large distance is not a proof of a good turning radius.

Physics tell us that even with a 50g acceleration the missile turn radius will still be quite large (>1 km), at close ranges missiles with TVC (IRIS-T, AIM-9X or MICA) will have the advantage.

No mate, you are missing the concept of lateral translation... a missile that pulls 80G at mach 2.5 will translate at a slower rate and a cover a smaller lateral distance than the ASRAAM at Mach 3.5 and 50G... The only part of the envelope that could be inferior for ASRAAM - as I have stated - is within the immediate vincity of the aircraft... i.e. within the first few hundred meters... In most situations this won't be an issue at all seeing as the ASRAAM has 180 degree off the rail performance.

It might however be an issue in an over the shoulder shot where the two jets cross each other... i.e. whether the Pro-Nav system that handles over the shoulder shots points the ASRAAM in the right direction to where the crossing jet is going or if it points ASRAAM to where it is just before they cross. Then it depends on how quickly the ASRAAM accelerates as it might find itself to fast to turn within the required circle.

Also could you explain why TVC gives them more agility than ASRAAM?

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Apart form all the spin that is spewed here, you know that ASRAAM was designed to engage soviet bombers over extended range with ripple fire of asraam without merge, knowing very well agility of the tornados....

I don't know that. AFAIK, Soviet bombers were meant to be engaged with Sky Flash, & later (but the USSR went away . . . ) AIM-120.

IIRC ASRAAM was meant to fill the gap which was perceived to exist between the engagement range of AIM-120 (under development at the same time) & the short-range IR AAMs previously used, while remaining capable at short ranges. Any reduction in agility is supposed to be compensated for by its high speed: the target has less time to evade it.

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This goes directly against MBDA own brochures:

Cooling system

Accepts argon, nitrogen or air supplies

Every single source I've seen state the the ASRAAM (and IRIS-T) seeker uses a classic Joule-Thomson cooler.

You are correct: "The coolant supply system for the IR head is installed in the launcher, and the seeker can be cooled using argon, nitrogen or air. "

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Check out the Youtube video for AIM-9X scenarios:
http://www.youtube.com/watch?v=4g4_jzqBJnA&feature=related

Anyone have decent IRIS-T and/or ASRAAM videos?

Its turning very fast, almost directly off the rail. Its much easier to put the agility on the missile than the aircraft - although obviously aircraft agility is still important.

The US requirement was for something like 10000 AIM-9X, hence the need to reduce costs with AIM-9M component re-use. It has sold to at least South Korea, Switzerland and others.

For comparison the UK has ordered something like 1300 ASRAAM, Germany 1250 IRIS-T (reduced from 1812) - Germany also reduced Meteor from 1480 to 880.

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15 years 6 months

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No mate, you are missing the concept of lateral translation... a missile that pulls 80G at mach 2.5 will translate at a slower rate and a cover a smaller lateral distance than the ASRAAM at Mach 3.5 and 50G...
Well, in case of >90° shots shouldn't you try to minimize lateral translation?
The only part of the envelope that could be inferior for ASRAAM - as I have stated - is within the immediate vincity of the aircraft... i.e. within the first few hundred meters...
I agree. That's the part where TVC gives an edge, cutting the minimal engagement distance by half.
It might however be an issue in an over the shoulder shot where the two jets cross each other... i.e. whether the Pro-Nav system that handles over the shoulder shots points the ASRAAM in the right direction
I'm not sure I understand. Lock on after launch shots should rely on the trajectory fed in the missile INS, pro-nav is only used once the target is locked by the seeker. As IRIS-T or AIM-9X don't have an INS as far as I know, this is an advantage for LOAL shots if the seeker can't aquire the target within a couple of seconds.
The US requirement was for something like 10000 AIM-9X, hence the need to reduce costs with AIM-9M component re-use.
They might also not want to canibalize AMRAAM sales.

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17 years 10 months

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Well, in case of >90° shots shouldn't you try to minimize lateral translation?

No - there is no point in minimising translation as it is the measure - of the missiles anti-dodge capability.

I agree. That's the part where TVC gives an edge, cutting the minimal engagement distance by half.

It is not so much about TVC as about speed - the only reason ASRAAM could be weaker here is because it might accelerate to a point where it is traveling to fast to react... which is what I tried to hightlight with regard to your response below.

I'm not sure I understand. Lock on after launch shots should rely on the trajectory fed in the missile INS, pro-nav is only used once the target is locked by the seeker. As IRIS-T or AIM-9X don't have an INS as far as I know, this is an advantage for LOAL shots if the seeker can't aquire the target within a couple of seconds.

Sorry what I am trying to say - doesn't just relate to > 90 deg shots - I am talking about crossing shots - if the pilot fires within very close proximity of the 2 jets and the missile is then sent straight for where the target is at the point of firing but the 2 jets and the missile cross - resulting in the missile needing to turn 180 degrees - IF the ASRAAM has got to a point where it has accelerated to quickly and is already up to say Mach 2.5-3.5 the resulting arc and turning circle might limit its engagement envelope... if on the other hand it is accelerated slower to turn its body around and then futher accelerated... it will have no problem.. I am just highlighting where this extra speed might become a problem...

On the other hand if the seekers Pro-Nav or the onboard LOAL + missile inertial nav system forces the missile off the rail into the correct trajectory immediately then again it will have no problem...

Cheers

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ASRAAM demonstrated a kill on a target more than 7 miles away. That's hardly a demonstration of a good short-range turn radius that is needed in a dogfight with HMS.
CAMM is ASRAAM with TVC, a datalink and I'd bet they're going to add an integrated cooler because regularly filling up missile canisters with nitrogen is definitely not a great idea.

Once they've done that, they'll basically have reinvented the MICA. Might have been a tad more cost effective to start with the MICA frame and use their own seeker...

The catch with MICA is its a rather pricey system and a French solution.

CAMM will be easier to integrate with Typhoon and is a British project, it should also offer a choice of seeker radar/IR. The Radar seeker option will also make it a rather attractive budget alternative to METEOR and AMRAAM.

The RAF will also find CAMM attractive as the RN and ARMY will stump a proportion of the development costs for the naval and land versions. Well I say the naval and land versions as they will retain the rail lugs from the aircaft version.

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Aim-9x Block 2 has LOAL, a GPS INS, 3rd party targeting, lofting profiles, and a Data Link.

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I thought CAMM is currently planned as TARH only?

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The catch with MICA is its a rather pricey system and a French solution.

CAMM will be easier to integrate with Typhoon and is a British project, it should also offer a choice of seeker radar/IR. The Radar seeker option will also make it a rather attractive budget alternative to METEOR and AMRAAM.

The RAF will also find CAMM attractive as the RN and ARMY will stump a proportion of the development costs for the naval and land. Well I say the naval and land versions as they will retain the rail lugs from the aircaft version.

...I'm not 100% sure on this, but wasn't CAMM included within the 'enhanced missile cooperation frame-work' WITH France? (I had been under the impression that CAMM would be more analagous to a MICA Mk.2, with France on-board. Or not?)

tredging on with the not-invented-here provincialism makes zero sense while claiming to want to maximize procurement efficiency. that's it's the same company (MBDA) just makes it more absurd. if MoD does end up treating CAMM as a purely UK project, it looks like France will at least feel FLATTERED by the gesture.

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Cheers
Many thanks for the explanations.

But you stated:

if on the other hand it is accelerated slower to turn its body around and then futher accelerated... it will have no problem..
Is the ASRAAM engine throttable? Because otherwise the problem is the same whether the aircraft just crossed or is simply "sitting" at 10 hours less than a kilometer away. A missile without TVC won't be able to turn sharply enough to engage the target (not that it's a very likely scenario).
The catch with MICA is its a rather pricey system and a French solution.
Yes, I understand that and I'm not suggesting the UK procures a 100% French weapon. But it would seem smarter IMO to work on common platform as it would reduce the validation and integration costs by a large amount. It would also boost export sales by giving the customer more options which would reduce price through competition (e.g. do you want a French or a UK seeker on your missiles?).

On the system side both solutions use Seawolf containers so there might be some economy of scale at least.

Aim-9x Block 2 has LOAL, a GPS INS, 3rd party targeting, lofting profiles, and a Data Link.
And won't enter service for another two years. But it does make it a very compelling solution vs ASRAAM & IRIS-T.
I had been under the impression that CAMM would be more analagous to a MICA Mk.2, with France on-board. Or not?)
AFAICT, the evolutions for the MICA are covered by the MICA NT "Nouvelles Technologies" and are mainly related to seekers. VL MICA is now fully qualified after a 15 firings test campaign so there's no reason for France to invest in CAMM.