I'm sure there will be dozens of questions on terms and abbreviations as I work my way through, but here are just a few that I haven't already been able to work out; Cat 1, Cat 3 This comes up quite a lot when the diary covers Allied response/defense to enemy action. Example:- "Result of engagement one Cat 1 to RAF and two Cat 3 to LAA." I.F.F. example: with regards to a friendly aircraft "it did not show IFF" AALO e.g. "...AALO reported that prior to this raid..." V/A This keeps appearing as a location, e.g. "5 aircraft were reported near the V/A" Stooging e.g. regarding enemy aircraft "Tactics: stooging over sea" Battery Troops: I know each Battery consisted of 2 Troops (e.g. "A" & "B" or "E" & "F") but there is one mention of "Right Troop & Left Troop". Example: "On 22 Jun 207 HAA Bty of 73 HAA Regt relieved 167 Bty at S5 and S7, BHQ and Right Troop of 167 then relieved 314 HAA Bty..." Thanks for any help with this.