Talk:1.1-inch/75-caliber gun

Some personal recollections

I was a Navy fire control tech. between 1954 and 1958, trained on the Mk. 37 and Mk. 63 systems. Along the way, I picked up a bit of lore about the 1.1" guns (which I had thought were 50 caliber). Their pointing servomechanisms ("power drives", in Navy lingo) used friction clutches, but were so poorly designed that one story said the friction surfaces had to be replaced typically every six hours of service. I have some reason to believe that the drive motors ran at constant speed, and pairs of clutches, one for each direction of rotation, provided torque to the load. (See also the original torque servos, with cords wrapped around rotating cylinders, in the Bush differential analyzer.)

The mounts had a third axis, called cross-traverse, perpendicular to the elevation axis and to the gun barrels. For a fixed bearing and elevation, the four barrels could be swung sidewise, so that at high elevations, geometry approaching gimbal lock wouldn't cause grief.

(I'd dearly love to know about the fire-control system that generated the cross-traverse gun order! Dummy gun, by any chance?) Nikevich (talk) 17:57, 9 February 2011 (UTC)

Rowland and Boyd, p379, state:

"In the 28 months of grace afforded the United States before the war spread from the European continent, the Bureau initiated a series of projects to develop a heavy machine gun director. Equip- ments with designated mark numbers from 45 to 49 were placed on the drawing boards, and production was rushed on a Director Mark 44 which was to serve as a stopgap design for use on 1.1" and 40-mm guns. This was not an ambitious project. The Mark 44 was simply a target designator that could be used to control ma- chine guns in train and elevation. Its principal advantage was that it allowed the weapons to be aimed from a more advantageous location than at the mounts themselves, though it did utilize a large spotting glass that increased the effectiveness of tracer con- trol. The Naval Gun Factory rushed into production of the equipments in late 1941, but only 85 of the directors were ever built. Installations had to be confined to large ships that offered a fairly stable platform, and production difficulties were so great that adequate delivery schedules seemed impossible."

The confidential BuOrd volume on fire control states: "...that it was a simple dummy gun type of director...and...had no lead computing elements..." The production problems with the Mk44 are somewhat surprising as this director appears to be similar in function to the the RN's Mk I to III pom-pom directors, which appeared in the mid 1930s.Damwiki1 (talk) 22:26, 9 February 2011 (UTC)

Consistency

The History sections opens by saying this gun "was developed when the United States Navy's Bureau of Ordnance (BuOrd) decided that the M2 Browning was not adequate for future AA duties," but then quotes a BuOrd finding that the M2 and this gun were both "far from satisfactory."

So something has to change here. We need some reference from the 20s or 30s that explains why the 1.1" gun was developed, or maybe something that says that the 1.1" was never actually effective. Something where the explanation in Wikipedia's voice is consistent with the cited reference, anyway. 71.197.166.72 (talk) 20:37, 21 May 2016 (UTC)

I've added an additional quote to provide more information. Since most source material comes from the USN, longer quotes are useful. More to come.Damwiki1 (talk) 22:22, 21 May 2016 (UTC)

That helps a lot! Thanks. 71.197.166.72 (talk) 06:25, 24 May 2016 (UTC)

this is a bad cite for info

References

Chicago piano

The text notes that the weapon was referred to as the "Chicago piano" though nobody appears to know why. "Chicago piano" was also a nickname for the Thompson M1921 .45 cal submachine gun favored by Prohibition-era Chicago mobsters (cf. "Chicago overcoat" for coffin), so the name may be a carryover generically referring to a full-automatic weapon with a high cyclic rate. — Preceding unsigned comment added by Death Bredon (talk • contribs) 19:40, 18 September 2018 (UTC)