iyer m8, i only have city guilds 2 5 9 and 11 / 2 5 9 13 and a few btecs and that qualifys me to work on them, the more technical jobs though one of the licensed guy has to come in ie radios,nav aids etc. i fink as well if its cessna, could be desil and you need some other qualification of extnetion to sign them of. ill have a word in work tomorrow and get some proper info back to you