Given that the Invincible class didn't start build until 1973, it's not surprising they didn't get to play.
My late father was on the PR9 at AKR at the time. He told me they had protested to the 'planners' at HQ NEAF* who were cleverly trying to task them down the same route and timings for days on end. It took a few days to sort out the madness but it took a strong intervention from the resident 1* to make it happen. He said they were given a Hunter escort, whose pilots had been briefed that they were not to engage if the PR9 was threatened and could only react under their own sovereign right of self-defence. The informal telephone briefing was allegedly rather different, the Hunter team making it quite clear that anything having a go at the PR9 would be engaged on the grounds that they themselves would obviously be next in line...
* This was the same HQ NEAF (same timeframe as Kuwait) that tasked a low-level oblique sortie to get imagery of a mysterious crate dropped off at Paphos by the Russians. Sqn calls the HQ: "Why don't we just send a photographer by road?" Silence at the other end of the call, followed by the tasker hanging up. Sortie cancelled shortly before launch.
