The only time 3.7 inch was used for direct support was in the breakout from Tobruk. They were also used in d/f mode by the Germans against a particular landing (canadian?) in the Sheldt estuary (germany liked the gun and used any captured ones, and had an ammo manufacturing line for them). Some may have fired in d/f mode in the rear areas in France 40 as well.
Ahah - the germans used them to defend Walcheren Island
Walcheren
The 3.7 inch gun had precisely
no sights fitted. Non, nada, zilch. I have seen a picture of one used in detached mode at Tobruk harbour - where the Australian(?) gunners had brazed a rough and ready AAA wheel ring sight to the bore.
The 3.7 inch AA gun only had pointer dials to follow from the central director for barrage fires. Direct (e.g AT) fire was done firing pairs of guns following the director sights in the rare circumstance of some of these things firing direct. The gun was sen as a theatre AA asset - for use in rear areas to protect areas against high altitude bombing.
It was very heavy, as it employed powered elevation etc, and needed to be emplaced on a solid platform, in cases where it was to stay about for a while - it was preferred to lay a concrete base for this. it was also rather big, and hence not easy to hide if used tactically. (In fact - the majority were the semi-mobile mk 2, as these were strategic assets - and this
required a concrete base to be bolted down to).
The 2 guns used to support the breakout from Tobruk were moved into place to overwatch the are of operations during the preceeding night, to use darkness to hide the emplacing. They seem to have been used for direct fire HE support, not as ATG.
In the far East, once the Japanese air threat had virtually disappeared, the 3.7 inch AA guns were used as additional artillery. Limitations (not modelled in SP) were the extremely flat trajectory which meant they really could only engage targets in LOS (e.g. hilltops say). If needed, then just add a 25 pdr battery, and call it a "3.7 AA battery" (rename it in the sceanrio editor) or just assume some of the 25pdr in the XIV army locker were actually 3.7 firing as arty. Effects will be similar for game purposes.
As to why we dont bother with high level bomber AA guns firing in barrage mode:
- use of level bombers is extremely rare. (the level bomber class was really only introduced for "flying artillery" scenario use e.g in the Normandy attacks).
- The use of level bombers over the front lines will be well out of range of any medium and higher calibre guns, which woud be way back covering divisional and higher operational or strategic targets (railheads and so on).
- There is no way to code for director-only barrage fire. It could be done, but it is not worth the time and effort, as any such guns would be dead weight
unless the opposition brought level bombers to the party, and even if they did - the bombers will be there and gone in a move or 2. As I stated above - the level bombers are there for scenario designers to use in specific tactical-use scenarios where loads of bombers prepared the battlefield. In all these cases, having special heavy AA (which would not be there, or the bombers would not be used so) and the code would be worthless additions so that maybe 1 of 60 odds bombers just might be hit.
Paratroop transports can be engaged by e.g 37mm guns (regular AAA) as they are not flying at super-high bomber altitudes. And any folks left dangling under silk hankerchiefs will be gleefully shot at by all available riflemen etc as they drop..
Cheers
Andy