I've edited my earlier post about the belly gun to correct a few errors.
On the subject of Schrage Musik and Freeman Dyson's oft-quoted assertion that the Operational Research people at Bomber Command never discovered this method of attack, I can only say he was wrong. My understanding is that he never worked on the study of damage to our bombers by enemy defences and he may therefore not have been privy to the information that some of his colleagues were.
As I've already stated, Operational Research staff at B.C. produced monthly reports "Enemy Tactics Against Bombers" which contained a mass of intelligence information and which duly noted the increasing ratio of night fighter attacks from below as against on the level or above, etc.
In January, 1944 the report included a description of the S.M. method :-
" In view of the relative frequency of attacks by unseen aircraft, attention is drawn to four reported cases this month in which the enemy fighter was seen to make its attack from almost vertically below. One, a Ju88, followed a Lancaster for a considerable time, positioning itself underneath the rear turret so that the gunner could not bring his guns to bear. From this position the fighter was able to open fire several times."
By July, 1944 Bomber Command had been handed an accurate description of a S.M. equipped night fighter:-
"Some fighters are carrying 20mm. upward firing cannon mounted at an angle of 70deg. to the horizontal. Aiming is done with a Revi gunsight inclined at the same angle as the guns. A tentative estimate of fighters so equipped was 10% or 20%."
I'll leave the last words to the big man himself, in correspondence with the Air Ministry:-
