The Alpha's are used for training on small Helo's (Kiowa's), we also wear them as test flight crew techo's on BH's.
I think it has something to do with NVG's, but all the BH drivers and sandbags (loadmasters!) all wear HGU's..
Would have to ask someone in ALS for more info, doesn't Jane's tell you?!
The MRH and ARH have different helmets again..but thats because they have lots of electronic goodies in them
