Formation sign on Airborne Helmet HSAT

[DougSA]

Any ideas on which formation/unit this one would have belonged to? White number 2 on red triangle.

It is on a 1956 dated helmet. Original wearer evidently a "Jones" "...922" of " A Sqn" (although also worn by a "Wood" at some point).

Interesting to see the battered - not so symmetrical - shape of this one! Seems to have had a hard life.

Insights appreciated!