NigG,
Welcome to our Old Crewroom in Cyberspace - and well met, Sir !
.... In fact, they did continue to operate after the other VV squadrons had been withdrawn. The vertical dive started at about 12000', the aircraft finishing at maybe 200', and the pilot had to aim at the target, so low cloud made it unworkable. However, 84 developed a low level dive, which was less accurate, but still pretty effective..
This puzzles me. I believe the decision to halt VV operations (on the onset of the '44 monsoon) was a policy one made by "Command" (in our case AHQ, Delhi). As to the exact date the axe fell, I cannot really help, as I was away recuperating from injuries sustained in my forced landing on 24th February, and did not come back until it was all over. Mistaken policy though it was (IMHO), I see no reason why it should not have applied to all the Squadrons.
We had all tried shallow dives (ca 45°) in monsoon weather, but discarded the idea because the famed VV accuracy had gone (the enormous nose of the VV plus the extra AoA from the zero AoI made for very poor forward visibilty) - and in any case the Hurricane and Beaufighter could do the job better, as they could see where they were going, and were much more agile - both important considerations when you are dodging round the jungle hills low level in pouring rain !
To carry out a "standard" VV dive, the drill was to start, as you say, from 10-12,000 AGL. You
must be able to see your target from there (the leader above all, as unless he starts his dive absolutely vertically, the rest will be "off" increasingly as they follow him down). Trial and (lethal !) error had shown that if the average chap pulls as hard as he can (to the point of "grey-out") as the altimeter passes 3,500 AGL, he will finish level at 1,000 or so. That sounds a fair margin, but as you were coming down at terminal velocity (300 mph with dive brakes out), it works out at 400 ft/sec - or 2½ seconds leeway. You hadn't a lot to play with ! Of course, you would not pull to be level at 1,000 (making yourself a fine target !). but eased off at the end to get down to the treetops ASAP with most of your 300 mph, you would be very unlucky to be hit then.
...You question why the VV didn't have more problems with Oscar fighters. In fact, the Allies had nine times the number of squadrons as the Japs, over Burma, in support of the '44/'45 offensive ... definite air superiority! Squadrons of Spits and Hurricanes were doing an excellent job of knocking down enemy aircraft...
So they were (but not until the Spitfires came on the scene !) And they cannot be everwhere at the same time. But Burma is a big place; there were no "Early Warning" systems; the Vengeance "boxes" on Army Support simply took off to reach target at a time fixed by the Army. Then the troops would close in to 100 yards on the Jap bunker or other strongpoint, ready to fire the mortar smoke bomb onto it when they saw and heard us coming. 24 bombs, four tons of HE, would go into the bunker area in 20 seconds, any surviving Jap would be so dazed by noise and blast that he could offer little resistance when the troops rushed in with grenade, rifle and bayonet to mop up.
...rarely flew with fighter cover...
True !
...So if enemy aircraft were sighted in the target area, the mission would be delayed until it was 'safer' to operate...
Never heard of that - ever (except in the case of the Jap high level .air raid on Khumbirgram - my Post on "Gaining a RAF Pilot's Brevet in WWII" Thread p.136 #2710 -"Danny loses an Elephant").
Enough ! I must go now, will be off line....I may be gone some time...
Danny42C.
PS: Agree - you Dad should have got the DSO (unless he got the DFC for shooting down the Oscar ?)