F-22 and F-35 vs. the infrared threat

F-22 and F-35 are definitely stealthy in the X-band, being able to slice off the enemy’s radar ranges to point blank where they have plenty of time to launch their AMRAAM. However in the infrared spectrum it is a different story. IRSTs are capable of finding targets tens of km away. IRST has some limits such as the narrow FoV, but as technology progresses, they should scan very fast like a narrow AESA.

The F-35’s EOTS sensor is said to have a range of ~70 km to form a fairly clear ID image. That means detection ranges are far greater even against frontal targets moving subsonically lets say 200 km. The Chinese claim their EOTS-ripoff can go up to 150 km to detect the F-22. The older PIRATE IRST is said to be capable of finding an F-22 around ~50 km.

F-35’s EOTS IRST:
https://www.youtube.com/watch?v=L2q65qOl1tM&feature=player_embedded

Chinese EOTS ripoff:
http://defence.pk/attachments/1507151009_86832-jpg.239664/

Although the F-22 and F-35 do have some IR countermeasures, such as skins and suppressed engines, they are no way going to be stealthy as the radar aspect. Flying very slow added with the skins may slice the detection range to a couple tens of km, but I doubt it would be enough to put the enemy at a firing range similar to the AIM-120’s effective ranges.

Would the F-22 and F-35 in the future have to fight at super low altitudes(like 6 km alt), where there are most atmoshperic vapor where IRST cannot see them? The AMRAAM’s range would be severely degraded at those altitudes lets say 10 km effective only. A very poweful radar like the PAK FA’s N036 may detect it at those distances. However I wouldn’t call it handicapped.

Of course the F-22/F-35 can fight at normal altitudes, the F-22 being very fast can outaccelerate most planes to throw its BVR missiles plus have a very powerful 2000 T/R module radar to jam most missiles fire control, however as newer missiles like ramjets and dual pulse, the US really needs to invest in better missile tech.

Stealth of course is really effective in the ground attack role, since ground IRSTs don’t really exist for systems like the S-400 due to clouds probably. Only short ranged SAMs like IRIS-T and SA-6 use infrared TV cameras.