Some of the systems possibly are, but the stock control isn't. It's not run by the RAF anymore though, but as I'm at work I'd probably better not name the supplier!
It's actually not a bad little system at all, the latest version has a few (IMHO predictable) issues and I preferred the older version, but it's not bad in the least. When I was on a course relating to administration of the system, one of the RAF boys teaching proudly said that it had never successfully been compromised or hit with malware. Two seconds later he looked pointedly at me and said "and no, that's not a challenge!".
The biggest issue with the system now is the outsourcing of support. There are things that I could quickly fix when we had a server here, now that it's all centralised you have no choice but to use the call-centre. Still that's the way a lot of things are going!