IRST debate still open?

I find the F-15C IRST program vindicates the European/Russian position on the matter.

 

http://www.lockheedmartin.com/products/InfraredSearchTrack/index.html

 

40 times more accurate than radar? This invites some discussion.

Very interesting indeed.

 

More here:

http://ericpalmer.wordpress.com/2010/04/03/irst-the-fa-18e-super-hornet-canada-and-australia/

 

Lockheed Martin brochure:

http://www.lockheedmartin.com/data/assets/IRST-FA18-Product_Card.pdf

 

The "40 times more accurate than radar" probably refers to the angular resolution. This is set by the diffraction limit which scales as the wavelength of the radiation over the diameter of the receiver. So for an X-band radar (3 cm wavelength), a 50cm diameter receiver has an angular resolution of order 3 degrees. This IRST pod is said to work at "long-wave infrared", so if we assume wavelengths of 100 micron, the 23cm sensor would have a diffraction limit of 0.03 degrees, so easily a 100 times better.

Edited May 9, 2010 by Case

radar has much wider wavelength no wonder IRST is more precise... ;) Nothing new (F-14D? hmmm).

 

Same technology applies to litening AT and sniper XR which can both lock onto and ID airborne targets as much as ground ones. The term "long range" is relative here (for an optical system).

 

Cant see through clounds and it doesnt work as, or replace the radar. Not by a long shot.

Edited May 9, 2010 by Pilotasso

Cant see through clounds and it doesnt work as, or replace the radar. Not by a long shot.

Where does it say it replaces radar?

 

In the future we'll probably see a synergy between ISRT tracking and AESA ranging. The ISRT would be used only for tracking targets, and their positions on the sky would be used to phase up the AESA so it needs minimal radar energy to obtain range and LOS velocity. It'll have to big advantages; first the AESA radar doesn't have to do tracking, so it'll be free to range more targets, and second, it'll use much less radar energy so it will be much harder for targets to detect they are being tracked and ranged.

Its just a product advertisement, I think they are going to always make it sound like the best product, they are trying to make sales. We can't really know how good or bad the system will be until you see it in action. Just my 2 cents

- it is not meant to replace radar but to be part of an advanced sensor fusion system that enhances SA;

- the fact that US Navy wants it for Super Hornet must mean it has different capabilities than eg ATFLIR.

Sniper etc can be slaved to a radar lock, but here the idea is to search and track with the IR channel. It can help to disambiguate a radar contact as being composed of two fighters in formation.

IRST has some inherent advantages that make it an ideal supplement for radar. It's passive, so you can sneak up on sombody more easily. The better resolution has already been mentioned. Also, AFAIK, current fighter generations do not carry IR jammers, therefore it would be jamproof (arguably, this is rather pointless, as the maximum range of the IRST might be inside the burn through range of the radar vs fighter sized jammers).

 

Still, i always wondered why western fighters have no IRST (save the F-14).

Same technology applies to litening AT and sniper XR which can both lock onto and ID airborne targets as much as ground ones. The term "long range" is relative here (for an optical system).

 

 

BTW is this increasing somehow the AA capabilities of A-10C, or the lock on an airborn target is the same as in A-10A?

BTW is this increasing somehow the AA capabilities of A-10C?

 

Yes, the lightning pod is AA capable.

Still, i always wondered why western fighters have no IRST (save the F-14).

 

They do now. Well the Typhoon FGRMk.4 block 5 and some block 8s do at least.

Yes, the lightning pod is AA capable.

 

Honestly I'm not sure about that. That would mean Litening can do something like Shkval? (Given that it is no IRST and there is no radar on board of A-10C?)

Honestly I'm not sure about that. That would mean Litening can do something like Shkval? (Given that it is no IRST and there is no radar on board of A-10C?)

 

It is more sophisticated at aquiring targets than the shkval, but basically yes. It is no IRST, but a rather advanced FLIR/DTV. In any case, it's a large improvement over the A-Hog.

Where does it say it replaces radar?

 

In the future we'll probably see a synergy between ISRT tracking and AESA ranging. The ISRT would be used only for tracking targets, and their positions on the sky would be used to phase up the AESA so it needs minimal radar energy to obtain range and LOS velocity. It'll have to big advantages; first the AESA radar doesn't have to do tracking, so it'll be free to range more targets, and second, it'll use much less radar energy so it will be much harder for targets to detect they are being tracked and ranged.

 

Current AESA's signals are hard to intercept to other fighters, you realy dont need IRST to track anything short of a heat seeker launch off boresight. Electro optical devices these days are best used to ID targets when rules of engagements requires it, or slave radars and other sensors from helmet inputs. This is the type of use pilots are commenting.

 

Not to open up the radar is a safe measure against ELINT in peace time. At war you want to use AESA for engagements. I just dont see the logic of keeping one target locked with IRST to track others with the radar, it wont need that at all. Further, IRST gimbal limits are much more limited than that or radars these days.

Edited May 9, 2010 by Pilotasso

I just dont see the logic of keeping one target locked with IRST to track others with the radar, it wont need that at all. Further, IRST gimbal limits are much more limited than that or radars these days.

You don't understand. You use IRST for tracking, and AESA for ranging. Once you know where the target is relative to your plane, and IRST gives you this to the arcminute level, you can just do a targeted send with the AESA and do a targeted receive, all this done with minimal radar energy.

Something doesnt add up with your post...while I inderstand the principle of it, it doesnt seem to follow the actual employment of low power modes of current AESA equiped aircraft because they are all western and with the exception of F-16 block 60 the rest have no IRST at all.

 

low power modes advantages have all been mentioned to be in in network context (you also cant locate source when aircraft hand off radar data to the other by turns serveral times a second), rather than with IRST, has never been used that way to my knowlege, and the comments I get from its usage by actual pilots suggest electro optical systems are used in different ways and for different purposes than that you described for AA combat.

 

Also cant see what practical advantage you would get since AESA pretty much can see detail down to centimeters and refresh it in real time... the difference between X band and IR is merely academic and should not have any meaning or be noticeable in combat.

Edited May 10, 2010 by Pilotasso

Something doesnt add up with your post...while I inderstand the principle of it, it doesnt seem to follow the actual employment of low power modes of current AESA equiped aircraft because they are all western and with the exception of F-16 block 60 the rest have no IRST at all.

That is why I said "in the future".

 

Radar warning receivers will obviously improve just like radars do. What may be common practice and hard to detect now will not stay like that for ever. That is why I think passive systems such as IRST will become more common place and will be linked with radars.

Honestly I'm not sure about that. That would mean Litening can do something like Shkval? (Given that it is no IRST and there is no radar on board of A-10C?)

 

Most TGP I know are A2A capable. At least I have seen several videos with TGP targeting aircraft

Look at 1:56, and it show tracking Aircraft in several other parts of the video

Look ate 0:38

http://www.youtube.com/watch?v=mTFcmlbn1GQ

There more, I just got to find them, gimme me a minute

 

Ok so it took more than a minute :D check 1:02

http://www.youtube.com/watch?v=mTFcmlbn1GQ

0:41

 

At any rate, I do not think it would improve the A-10 A2A capability, but the Pods are capable of tracking airborne targets.

Edited May 10, 2010 by mvsgas

That is why I said "in the future".

 

Radar warning receivers will obviously improve just like radars do. What may be common practice and hard to detect now will not stay like that for ever. That is why I think passive systems such as IRST will become more common place and will be linked with radars.

 

 

 

Ah we are in the nostradamus mode here then. :D I still think not, since IRST has much shorter ranges, prone to be bloked by moisture and IR signature is much lower on modern aircraft not to mention a few actualy supress it. You will have to swich on the radar or else risk seeing your oponents second, which is bad. ;)

 

Imagine you passively tracking a target and ping it like you do in lockon...then the target passes behind a cloud or swiches afterbutner off and your radar lits up in full force in the least convenient moment...or loose track alltogether. :)

Edited May 10, 2010 by Pilotasso

Pilotasso, if your analysis is right than I really cannot understand this:

 

http://www.lockheedmartin.com/news/press_releases/2010/MFC_042810_LM_DevelopingF-15C_IRST.html

 

(posted by Groove in news section)

 

This is recent: it is big money, it is poored into exactly what you claim to be not working and even more so, it is exactly what Pirate sensor is for on Typhoon.

...hhhmmmm where did I say it wasnt working in what way?

 

Further, the article pretty much reinforces what I wrote.

Imagine you passively tracking a target and ping it like you do in lockon...then the target passes behind a cloud or swiches afterbutner off and your radar lits up in full force in the least convenient moment...or loose track alltogether. :)

Yes, water vapour will absorb infrared radiation, but not at all wavelengths, and never for 100%. Yes, clouds are in the sky, but hardly at all times at all altitudes and in all directions. Yes, targets may change their throttle so IR radiation diminishes, but targets may be visible out of afterburners. Yes, radars may go STT on a target in LockOn, but perhaps they do not in the real world.

 

These systems ADD to the radar, and if you can do track targets passively, albeit not always, it will always be better than doing it actively.

Your post now is correct, but what you described earlier is simply not a doctrine in combat, specialy when considering LPI AESA's. Theres logic to what you said but its just speculation.

There is indeed almost nothing known about how Pirate sensor is used in A2A; Some Rafale pilots described tactics with OSF and MICA-IR; but first of all OSF has some issues with the IR channel and normally works DTV, and second there is no real sensor fusion; there is some master/slave integration with radar though.

 

I guess US ambitions are for tight integration with the AESA.

Your post now is correct, but what you described earlier is simply not a doctrine in combat, specialy when considering LPI AESA's.

Then you misread my post, as I said nothing about present doctrine.

didnt misread anything, both the quote you made, and your posts are not missdirected.

 

Tflash, we are talking about single digit to low double digit miles range figures for electro optical devices, AESA's go into realm of triple digit range, how far (sorry for pun) does your notion of IRST with AESA integration go? ;)

Edited May 10, 2010 by Pilotasso