BVR, Datalink, Aim 120 and Meteor

[sinistercabbage]

Hi guys, I m new to the forum and was just curious if anyone would be able to answer my questions.

First of all my understanding on the subject. Aim 120C can be programmed to be fired onto a target using data transmitted from a friendly, be it another fighter or AWACS. Normally mid course guidance updates would be provided by the airplane's radar via data link. Is there anything stopping the plane from uploading data link (mid course) info from AWACS to the missile or is this only possible using data from the planes own radar? As to my understanding AWACS can continuously keep updating aircraft (128?) around it on location of enemies.


AIM 120D and Meteor, from what I have read definitely have these third party capabilities. I.E AWACS or other ally can transmit the mid course data updates to the airplane that has launched the missile. Can the launching airplane therefore take evasive action and just relay targeting data to the missile? Or is the transmitting done via the FCR? There is no direct link from third party to the missile? Its always through the launching aircraft?

Another question is, F22 cannot transmit with Link 16, it can only receive. Instead it has IFDL. Can it use this system to provide mid-course updates to its missiles?

I'd be really thankful for answers on these if you can of course. I can't figure it out myself

[wrightwing]

Hi guys, I m new to the forum and was just curious if anyone would be able to answer my questions.

First of all my understanding on the subject. Aim 120C can be programmed to be fired onto a target using data transmitted from a friendly, be it another fighter or AWACS. Normally mid course guidance updates would be provided by the airplane's radar via data link. Is there anything stopping the plane from uploading data link (mid course) info from AWACS to the missile or is this only possible using data from the planes own radar? As to my understanding AWACS can continuously keep updating aircraft (128?) around it on location of enemies.


AIM 120D and Meteor, from what I have read definitely have these third party capabilities. I.E AWACS or other ally can transmit the mid course data updates to the airplane that has launched the missile. Can the launching airplane therefore take evasive action and just relay targeting data to the missile? Or is the transmitting done via the FCR? There is no direct link from third party to the missile? Its always through the launching aircraft?

Another question is, F22 cannot transmit with Link 16, it can only receive. Instead it has IFDL. Can it use this system to provide mid-course updates to its missiles?

I'd be really thankful for answers on these if you can of course. I can't figure it out myself

A- yes. 3rd party targeting allows evasive action.
B- F-22s don't use Link 16 to guide missiles (or IFDL for that matter.)

[sinistercabbage]

A- yes. 3rd party targeting allows evasive action.
B- F-22s don't use Link 16 to guide missiles (or IFDL for that matter.)

A- But the guidance is still through launcher aircraft?
B- So I presume no one bothered giving them ability to guide missiles like that because they could close in to the enemy without need for longer range bvr shots?

[hornetfinn]

A. I'm pretty sure all current air to air missiles with data links get the data from launcher aircraft or possibly from wingman. AFAIK, all such data links use somewhat directional antennas looking back towards the launcher and are not omnidirectional. So that alone restricts how updates to the missile can be transmitted. This method makes it more difficult to detect and jam the data link though and allows using lower power levels. "Real" data links need too big and heavy hardware (terminal, radios, antenna) and need too much power for air to air missile use at least currently. Link 16 especially also has large latencies which makes it poor choice against fast moving targets like aircraft. Air to ground munitions are getting Link 16 networking capabilities

The data link is usually done using the fire control radar or using specialized antenna (Mirage 2000 uses this method as well as ground launched systems). Fire control radar usually transmits the data in the sidelobes (especially with mechanically scanned radars) or using dedicated beams for that (especially AESAs can use this method).

B. All aircraft including F-22 use dedicated missile data links to "talk" with air to air missiles. Nobody currently uses such data links like Link 16, IFDL or MADL for air to air missiles. AFAIK, F-22s are being upgraded to use AIM-120D with two-way data link and that they have always had one-way data link for earlier AMRAAM models.

[sinistercabbage]

So the logical consequence of mid course updates being given via FCR is that the launcher has to point its nose towards the missile and the target (roughly). Turning back whilst providing mid course updates is therefore not an option unless you were to install a rear facing transmitter. But would then the datalink connection need to be reestabilished? From what I know once you turn back connection with the missile cannot be reestablished.

I'm pretty sure all current air to air missiles with data links get the data from launcher aircraft or possibly from wingman.

Now, does that mean older missiles like AIM 120C can also receive mid course updates from AWACS via launching aircraft? If so why would this be so heavily advertised for Meteor for example.

A two-way datalink enables the launch aircraft to provide mid-course target updates or retargeting if required, including data from off-board third parties.

- the quote can be found on Saab website.

Two way data link, cool thats certainly a new capability, but are mid course updates from third party data new?

[marauder2048]

JLENS was able to execute forward-pass and engage-on-remote with essentially unmodified AIM-120Cs.

The typical issue for older missiles is that the midcourse update data was missile-centric which means
that the FCR has to translate the offboard target tracks into the missile's frame of reference.

For the smaller airborne FCRs that was a burden but the newer missiles with more computational
power, better IMUs, GPS and two-way datalinks can to this translation locally on the missile which
unburdens the FCR.

[element1loop]

But would then the datalink connection need to be reestabilished? From what I know once you turn back connection with the missile cannot be reestablished.

Besides probably not being correct, (as jamming could achieve similar) if it was once correct, it's also a 4th-gen tactical thought construct. There's no reason to tactically turn-away or stop supporting the datalink to higher pk intercept if you've been maximizing stealth tactics all along, and thus have not been detected, tracked, targeted, nor fired at yet (plus have outstanding EA and MDF support cues). A pilot could shallow spiral towards, in a combined further flanking move that likewise manages aspect and thus VLO profile, or else can zig-zag towards, to manage a more ideal angle to the target's vector (i.e. to leverage MDF data on the target's sensor FOV and range and remain in a more ideal angle to the target) and also to maintain radial distance longer. And thus to reduce the relative closure speed, thus providing enough time for at least two separate HOBS BVR shots to fly out if the first optimal pk % shot had actually failed, missed or else was trashed by MAWS directed maneuvers.

i.e. tactically dropping the missile datalink is unnecessary and fairly unlikely.

Particularly when your wingmen assist or distract an attacked target, using EA or even popping CMs. Hey,why not given they can't get a track or a lock and the wingmen can likewise be flanking on a radial track, or else slowly spiraling in towards to attain a second optimal firing position whilst also managing their VLO aspect. Thus simultaneously moving out of the target's detection sensor FOV and reducing the target's SA, and simultaneously lighting-up the targeted flight's MAWS sensors with a random flare-pop, or else a radar sensor with chaff to distract and bother the targeted pilot and his wingmen.

Pretty soon they'll either be hit, or else running away with low SA.

[element1loop]

Is there anything stopping the plane from uploading data link (mid course) info from AWACS to the missile or is this only possible using data from the planes own radar? As to my understanding AWACS can continuously keep updating aircraft (128?) around it on location of enemies.

RAAF's Project Jericho (transforming RAAF into a 5th-gen enabled Joint-force) implemented a "cooperative engagement" capability and tested it in Jan-Feb 2015 on E-7A Wedgetails with classic Hornet and AIM-120C5 (if I remember the open-source test schedule correctly, it could have been early 2016).

[wrightwing]

A- yes. 3rd party targeting allows evasive action.
B- F-22s don't use Link 16 to guide missiles (or IFDL for that matter.)

A- But the guidance is still through launcher aircraft?
B- So I presume no one bothered giving them ability to guide missiles like that because they could close in to the enemy without need for longer range bvr shots?

No. The guidance can be the launch aircraft or from a 3rd party. Link 16/IFDL/MADL is how platforms share data with other platforms. It's how F-35s can provide targeting data for SM-6 missiles over the horizon, or for HIMARS/MLRS, or other fighter aircraft.

[wrightwing]

Put differently the launch aircraft can immediately evade, while a 3rd party guides the weapon.

[marauder2048]

Confusingly, sometimes there's a distinction made between third-party targeting and offboard targeting.

In the former, inflight target updates are transmitted to the shooter via a non-weapons datalink (e.g. MADL)
and then to the weapon via the weapons datalink.

In the latter, inflight target updates are communicated directly to the weapon via a weapons datalink
from a platform other than the shooter.

[Scorpion1alpha]

To the OP, please post future topics in the correct forum.

[hornetfinn]

Whether missile can be guided from third party or off-board is more about the aircraft capabilities and not that much to do with missile data link. The missile doesn't really care where the commands come from if they are in correct format and pass through crypto etc. So if the aircraft avionics has the ability to pass third-party target data to missile, the missile data link is not a problem.

For offboard targeting, the launcher and targeting aircraft need to communicate enough to have mutual understanding about the launch and how to communicate with the missile. Launcher needs to tell the missile initial target parameters and what data link settings are used. Guiding platform needs to know these same things and also know when the launch has happened so it can start sending guidance information with correct settings at the right time to right direction. The missile likely doesn't have any idea that it's actually guided by someone else than the launcher.

[sinistercabbage]

Whether missile can be guided from third party or off-board is more about the aircraft capabilities and not that much to do with missile data link. The missile doesn't really care where the commands come from if they are in correct format and pass through crypto etc. So if the aircraft avionics has the ability to pass third-party target data to missile, the missile data link is not a problem.

For offboard targeting, the launcher and targeting aircraft need to communicate enough to have mutual understanding about the launch and how to communicate with the missile. Launcher needs to tell the missile initial target parameters and what data link settings are used. Guiding platform needs to know these same things and also know when the launch has happened so it can start sending guidance information with correct settings at the right time to right direction. The missile likely doesn't have any idea that it's actually guided by someone else than the launcher.

So do we know if the capability for offboard targeting exists with main platforms that will carry the Meteor or AIM 120D? The little information there is seems to point to third party targeting rather than offboard targeting.

Also does the guiding platform really need to know all this info? After all the missile should know its position, especially with addition of GPS.

The missile doesn't really care where the commands come from

But as you said that would also depend if the datalink antenna is omnidirectional.

No. The guidance can be the launch aircraft or from a 3rd party. Link 16/IFDL/MADL is how platforms share data with other platforms. It's how F-35s can provide targeting data for SM-6 missiles over the horizon, or for HIMARS/MLRS, or other fighter aircraft.

Thats interesting, do you any info on the mechanism of this. I did find several articles which were perhaps not very clear.
The best I found is this quote from Raytheon.

During this capability demonstration, the SM-6 received continuous updates from the network, including the fighter aircraft, leading to the successful intercept of the target.

Now, I could still be a little pedantic and say thats its still a little ambigous. After all network updates from the F35 could have always went through the ship. The only source I found directly stating offboard targeting from F35 is vice news so..but I m still interested if you have any interesting sources.

Another questions is does Meteor and Aim 120D also work the same. As per Raytheon this was a capability demonstration. Would that mean the in service SM 6 missiles at the time of the test did not have that capability? As said previously the direct quotes we have about Meteor seem to point to third party updates rather than total offboard targeting.

RAAF's Project Jericho (transforming RAAF into a 5th-gen enabled Joint-force) implemented a "cooperative engagement" capability and tested it in Jan-Feb 2015 on E-7A Wedgetails with classic Hornet and AIM-120C5 (if I remember the open-source test schedule correctly, it could have been early 2016).

We are definitely talking of mid course updates relayed using data from E7A? In any case older missiles probably did not have a need for such ability. If we are launching an Aim 120B or C from 30 km away (so roughly their effective range against fighter) using AWACS or wignman data and the target is not aware of the need to manoeuvre the missile should have no problem to acquire the target just via its inertial navigation and seeker head. And even if the target manoeuvres its only c.10s between launch and when the missile goes pitbull. TBH in those 10 seconds, even if the aircraft was to manoeuvre I think it be quite unlikely for it to escape the detection range of the Aim 120.

You were also talking of 4th generation thinking. Indeed I was thinking of a situation where a 4th generation aircraft is flanking an enemy force and to avoid alerting enemy of their presence it can use AWACS to provide its long range missile with mid course updates, or even better complete offboard targeting.

[quicksilver]

hmmm...a newbie, eh?