Rigga, 431 MU would never have repaired CAT 4 or CAT 5 aircraft, CAT 4 was manufacturer repair using production / special jigs by CWP or back at their plant and CAT 5 = beyond economical repair/ totally fooked.. CAT 3 was the level they worked to, same as RSS did in the UK (bar all choppers that was the preserve of MARTSU then DARA Fleetlands). RSS did all the CAT 3's on the navy fixed wing fleet mind.
RSS still exists in some form based at St Athan... Been there 21 years in June (I escaped to Colt when it moved from Abo.) Any repairs to RAF fixed wing that is catorgorised beyond CAT 2 used to go through them for further assessment or repair (any repair over 250 hours to do was the old trigger) although I'm no longer in the loop if BAE have taken this over within their maintenance contracts for CAT 3 work during maintenance, as rumoured when I was leaving.. But you know more about that than I do!
