I thought the RAF already has (had?) NCA who aren't SNCOs?
I thought some junior ranks (stewards?) operated as cabin crew on VC-10s and Tristars?
I also thought that at one stage there were some of them on Herc Sqns. There was a legal requirement for there to be more than one person in the back once there were more than so many pax (50?). Rather than take two loadmasters it was considered more cost effective to take one loadmaster and some air stewards.
I'm not sure if either of these is still the case today.