How effective was Schrage Musik?

[Stephan Wilkinson]

I have seen accounts that suggest the effectiveness of Schrage Musik gun installations on a variety of night fighters was exaggerated. To the casual observer, the upward-firing device looks deadly and suggests that it was a piece of cake to fly under a Lancaster and blow it away, but I wonder...

Some have written that the installations were heavy and were often stripped out in the field, others have said that they had the unfortunate side effect of firing at an angle (typically 65 degrees, I think) that led to the attacking aircraft being hit by pieces of the bomber. They should have fired vertically, it has been suggested.

What is the truth of the matter? Was Schrage Musik deadly and effective, or did it look better than it actually was?

[VtwinVince]

I'm no expert on this installation, but I did talk to Guenther Bahr about it over dinner many years ago. He left no doubt as to the efficacy of this device in the right hands.

As I see it, it was deadly and effective when it was introduced. Allied aircrew often reported explosions of unknown source then, since they didn't see the fighter. Later, when this type of weapon became known to them, they knew what to watch out for and how to evade, so efficency and deadlyness might have decreased. And of course, flying just below an allied bomber and causing the bomb load to go off by hitting it with incendiary ammo would cause some trouble to the german Nachtjäger...

[Graham Boak]

In engineering terms, the installation of long guns vertically into a shallow fuselage, whilst ensuring feed mechanisms and low drag, doesn't seem achievable. In flying terms, aiming directly upwards wouldn't be particularly easy, nor maintaining formation on a bomber that could be carrying out unpredictable changes of direction. Both are much easier with the fighter positioned a little behind. Sometimes idealised theories don't work out for good practical reasons.

I suspect the choice of angle came from trials, and it is what it is because that worked best.

As for its success, I think that would need a good statistical study which, if it exists, I haven't seen. However the more successful fighter pilots seem to have favoured it, which is a fairly strong hint.

[Stephan Wilkinson]

All of the He-219s that flew in 1./NJG 1, the only squadron to be fully equipped with that aircraft, had their Schrage Musik guns removed. They weren't worth the weight penalty,the pilots apparently decided.

[Bruce Dennis]

I understand the angle was chosen after studying the movement of the pilot's head that was needed to keep track of both his instruments and the target: tilting his head all the way back was a no-no in night flying.

Bruce

[Denniss]

Originally Posted by Stephan Wilkinson

All of the He-219s that flew in 1./NJG 1, the only squadron to be fully equipped with that aircraft, had their Schrage Musik guns removed. They weren't worth the weight penalty,the pilots apparently decided.

Are you able to back this claim up with data or documents?
Would be more logical to remove the underfuselage weapons bay than the SM guns.

[he219research]

Actually (AFAIK), the angle of the guns (about 60-65 degrees) was choosen as this proved to offer the least risk of debris from the target hitting the attacking night fighter.

The actual aiming of the guns was done using a separate Revi 16 A-N sight: this was usually mounted in the upper part of the canopy, slightly above and in front of the pilot.
During an attack using the S/M, the pilot of the night fighter didn’t actually look straight up at the target, but instead taking aim through the mentioned Revi 16 A-N sight.

It can be worth noting that the weight of the S/M (2 x MK108 w. 100 rounds each) in the He 219 was enough to prevent full use of all four weapon stations in the fuselage tray: when S/M was fitted to the He 219, the two rearmost (centre) under fuselage guns had to be removed in order to keep the total weight down, as well as to not upset the aircraft centre of gravity.
Each MK108 with 100 rounds weighed roughly the same as one MG151/20 with 300 rounds (standard ammunition load for the He 219).

[Graham Boak]

I disagree. However useful against slow heavy bombers, the SM installation would be totally useless against Allied night fighters in the stream, or for intercepting fast Mosquito night bombers. Whether that was a factor in their removal in this particular case I cannot say, but the belly guns are more flexible operationally.

[Denniss]

He 219 had more than sufficient forward armament, even the 2x20mm gun in wing roots were sufficient, no need for four more. The 219 wasn't fast enough to catch Mosquitoes or night fighters and their main target were bombers anyway.

He 219 weapons manual does neither mention weight or CoG issues for removal of the center bay guns. Judging from the manual Section IIB the MK 108 uses the attachment points of the center bay guns.

For weight calculation one needs to add 2x compressed air bottles required for the MK 108.