Block 40 IFF and SEAD

I've been looking through several of the Aviano and Kunsan AFB Block 40s and I've noticed that in all of the photos, there are no traces of Block 40s carrying the HARM and even more interesting is that Block 40s fly without IFF interrogators. I know that the Block 40 can carry HARMs but does the USAF even use the Block 40 for SEAD and why don't Block 40s carry interrogators?

USAF Block 40s never received the AIFF interrogators due to either lack of requirement or lack of budget.

Budget requests from back in the day only show newer Transponders for USAF Block 40/42 (to replace the older Transponders). Whereas AIFF was listed for Block 50/52 only.


South Dakota ANG Block 40s do have AIFF - probably due to an Air Defense requirement - and this is fairly recent. There are some photos kicking about.

36FS 51FW PACAF has a SEAD mission and carry AGM-88 HARM. Not many other block 40/42 units who has the same mission, but the 36FS does.

Nearly all the ANG block 40/42 units have received the transponders. This is funded by the ANG budget state by state, which is a typical ANG feature of making the most of what they have. In addition ANG block 30/32 units have the same.

As for the SEAD mission, it is only the 148FW 179FS Minnesota ANG which has it, however they fly the block 50 so not subject for this thread.

SCANG still have SEAD don't they with Block 52s?

All F-16s have Transponders - I think you mean ANG Block 40 / 42 got AIFF which combine the Interrogator/Transponder. There is only one Block 40 ANG unit left that I can see (and 2 x Block 42).

You're right, forgot about 169FW 157FS. But I did write ANG