What were the weight savings from removing FW 190 outer wing cannons?

[Kutscha]

The RAE report on 5313, which can found summerized in the Swanborough/Green book on the 190, says 57kg for 2 MG FF cannons and 41kg for the ammo and mags.

I have also seen it claimed that the 115l aux tank was often removed to save weight in fighters but that the fighter-bombers kept it for some reason.

[George Hopp]

"The guns by themselves didn't weigh anything like that much - the 'Waffen' weight must include associated equipment, presumably to do with mounting the guns."

You're right, Tony, the basic MG-FF with EA-FF, ZVKS-FF, DS-FF, and EPD-FF weighs only 28kg (from the handbook of 1939, reprinted in October 1940). But, I imagine, that you also need to take into account the weapon mounting and its wiring and firing indicator, as well as the air bottle with its mounting and plumbing.

I have found no speed loss yet for the mounting of the MG-FFs in the Fw 190. But, I have a report on the difference in speed for a Bf 109E-3 with and without its wing-mounted MG-FFs. The difference was considered as Zero. There were 4 test flights, which gave the following results: 31.1.39 w/o 467 km/h, 8.2.39 w 467 km/h, 15.2.39 w/o 467 km/h, 16.2.39 w 466km/h. When the MG-FFs were removed, the openings in the wing leading-edge were covered.

[George Hopp]

"The RAE report on 5313, which can found summerized in the Swanborough/Green book on the 190, says 57kg for 2 MG FF cannons and 41kg for the ammo and mags."

I think that the weight stated for the cannons, was for the cannons alone, since each weighed 28kg, without taking into account all the ancillary equipment that the cannons needed to function. These would include the mountings, the wiring, the hot-air ducts, the cockpit rounds counter, as well as the air bottles with their plumbing.

[John P Cooper]

Just to add a bit more to this to for those whom want it:


MG FF/M Gewicht 28 kg Gewicht Trommel mit 60 Schuss 20,3 kg
(page 436 Peter Rodeike's book)

[Kutscha]

Originally Posted by George Hopp

I think that the weight stated for the cannons, was for the cannons alone, since each weighed 28kg, without taking into account all the ancillary equipment that the cannons needed to function. These would include the mountings, the wiring, the hot-air ducts, the cockpit rounds counter, as well as the air bottles with their plumbing.

Would the 'black men' go to all the trouble of removing all the ancillary equipment?

[George Hopp]

"Would the 'black men' go to all the trouble of removing all the ancillary equipment?"

It probably depended on the pilot. But, sometimes they would go to great lengths to increase the capability of their a/c, including stripping out everything that added weight, polishing the a/c for more speed, installing rear-view mirrors, and telescopes. So, they might or they might not.

[kb]

Having viewed several gun camera films showing FW190s suffering fatal damage resulting from explosion of the outer wing cannon ammo bays, I think I can see a reason why they would remove them.

[Josh Osborne]

Removing weight would have more of an impact on climb and maneuverability than top speed. For example, the lightened "Gypsy Rose Lee" version of P-40F only flew 4 mph faster than the standard version, yet more than a thousand (IIRC) were produced which saw heavy action in North Africa.