Only Paveway IV, and Enhanced Paveway II+III in reality.
Technically GR.7As also had EPW, but it was kind of part of the JUMP upgrades to GR.9.
Brimstone (the MMW-only one) was trialled and had emergency clearance. Harrier retired before Dual Mode Brimstone was in service. ASRAAM was planned, but cancelled quite early on because of the missile’s delayed entry in to service, and AIM-9L was considered sufficient for Harrier. Storm Shadow was planned but Harrier retired before it happened.
Still the same one AFAIK. It’s main use was navigation, so hardly needed to be high-resolution. The nose FLIR was pretty much surplus to requirement with a targeting pod being carried.
ALQ-126 was for American AV-8B. Ours never used podded ECM since Zeus has transmitter modules for jamming that the American ones do not.
Again, still Zeus.
British RWRs have been programmable and upgradable since the 80s, so there’s just a progressive update of threat libraries, and LRUs if they need hardware replacements.
GR.9 was going to benefit from more situational information provided by the TIEC datalink, with other aircraft and ground radars adding to the “sensor fusion” to improve the air picture. TIEC integration was still ongoing when the Harrier was retired.
Positional accuracy of locating threats benefitted from the addition of GPS.
Ed for clarity:-
A lot of what GR.9 was about, was simply standardising the Harrier fleet. Because by the mid-2000s the GR.7s were a total mixed bag with some planes having Mk.107 engines and others Mk.105s, some could carry TIALD and others couldn’t, some had a GPS and secure comms and some didn’t (which meant some could operate from carriers and some couldn’t), some could carry Mavericks and some couldn’t, and now some were getting Mil-Std-1760 compliant stores management for EPWs.
The issue of “fleets within fleets” needed addressing if Harrier was really going to operate in the Joint Force concept from land and at sea, and be able to move aircraft between squadrons at home and abroad.
The GR.9s brought them to a standard where they could do all those things, and were all the same in terms of avionics. The only real persisting difference was engines on the 9 vs 9A - which was a cop out because originally they were all meant to get Mk.107s and there would be no GR.9A.
Some of the more boring improvements were a new Successor IFF system (SIFF), a very advanced terrain-referencing system that provided capabilities for ground proximity warning, navigation and weapon delivery, and the ability to use the Rangeless Airborne Instrumentation Debriefing System (a digital ACMI pod - RAIDS is the all-white one that everybody confuses for ASRAAM in photos) for training.