Help With Abbreviation on WW2 record

[JTT]

I have just received my fathers RAF record from 1943-1947. There is one abbreviation that I can't find anywhere including the abbreviation list they send with the record.
It is mentioned in two places in his record, under Trade, and also under descriptions of promotion, he also mentioned it in his letters home that I have just found.
I'm attaching images of the letters, but it's AMA. I have drawn a black square(ish) round them. Thanks in advance.
And if anyone want to translate the Special Qualification section that would be good.
If it helps he was a Wireless Operator/Air Gunner

[rafcommands]

A very short lived 1947-50 method of describing aircrew ranks.

Aircrew (1 to 4) Master Aircrew

Everyone onboard the aircraft was an AMA

https://elliottmilitary.com/product/raf-master-aircrew-badges/

Captain and first pilot A1MA - first WOp/AG A1MA - first nav A1MA
2nd pilot A2MA - 2nd WOp/AG A2MA - 2nd nav A2MA

etc

not a liked system - became Master Signaller, Master Air Loadmaster ...

only rank to survive into modern usage is Warrant Officer Master Aircrew

Ross

[JTT]

Thank you so much Ross. It has been driving me crazy for months trying get an answer. No body seemed to know it. Thank you again.