WI - 1.1 inch developed as a Gatling type weapon

Just a random thought....

What if someone in the Navy looked at the 1.1 inch gun and thought about adapting it to a Hotchkiss revolving cannon and adding a motor drive...sort of predating the Vulcan by about 15-20 years...

Would this have a basis for an improved AA gun design that was far more reliable?
 

Driftless

Donor
Motor drive with ejecting all cartridges cyclically, whether fired or misfired, would have eliminated one of the historic problems with the weapon.
 
Just a random thought....

What if someone in the Navy looked at the 1.1 inch gun and thought about adapting it to a Hotchkiss revolving cannon and adding a motor drive...sort of predating the Vulcan by about 15-20 years...

Would this have a basis for an improved AA gun design that was far more reliable?

Good idea. Externally-powered guns can be more reliable than self-powered.
The 1.1in was a powerful cartridge, class of the German ammo for MK 101/103, or with about 50% heavier shell than French & Japanese 25mm AA. Or, 2/3rds of shell weight of the US or German 37mm AA from late 1930s/early 1940s.
Spin it to modest 2000 rpm and USN has a nifty AA gun.
 
Motor drive with ejecting all cartridges cyclically, whether fired or misfired, would have eliminated one of the historic problems with the weapon.

that's along the lines of what I was thinking, along with reducing complexity and weight...

If you could get it to fire 3-400 rounds per minute and add some sort of a powered mount as well...

then what about a smaller version to put on PT boats? sort of like the three tube 20mm used on Cobra gunships? Would have played havoc as a Motor Gunboat weapon...
 
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If you could get it to fire 3-400 rounds per minute and add some sort of a powered mount as well...

Your are referring to these available in bulk 1940-41?

Even at 1500 RPM it would be effective vs aircraft. Tho my question would concern range. Would it reach out and touch Japanese torpedo bombers long enough before they could release their payload?
 
Would an aircraft mount be possible? Sure, it’d weigh a bit and it’d need power, so not an air-to-air weapon, but perhaps an interesting anti-surface weapon (anti-tank, shipping, surfaced U-boats...)
 
Your are referring to these available in bulk 1940-41?

Even at 1500 RPM it would be effective vs aircraft. Tho my question would concern range. Would it reach out and touch Japanese torpedo bombers long enough before they could release their payload?

Wiki has a maximum range of 7000 yards...NavWeps talks about the tracer round having a max range of 3000 yards visibility...

I'm no expert on aerial torpedo delivery, but from what I've learned on here I guess 2000 yards is about the max distance for a drop...
 
Would an aircraft mount be possible? Sure, it’d weigh a bit and it’d need power, so not an air-to-air weapon, but perhaps an interesting anti-surface weapon (anti-tank, shipping, surfaced U-boats...)

could be possible with a 3 tube version....and as I said earlier, something that could be mounted on a PT boat as well with a manual mount...
 

Driftless

Donor
could be possible with a 3 tube version....and as I said earlier, something that could be mounted on a PT boat as well with a manual mount...

Think of the potential against the smaller craft of the "Tokoyo Express" and other Japanese resupply efforts in the Solomons.
 

SsgtC

Banned
Your are referring to these available in bulk 1940-41?

Even at 1500 RPM it would be effective vs aircraft. Tho my question would concern range. Would it reach out and touch Japanese torpedo bombers long enough before they could release their payload?
IIRC, most torpedo bomber pilots trained to drop their fish from inside 1,000 yards of the target. Or at least the IJN did. From 2-3,000 yards, that gives ships a lot of time (realitively) to comb the tracks and avoid them. So anything with an effective range of 3-4,000 yards should be plenty. At least for a close in weapon.
 
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IIRC, most torpedo bomber pilots trained to drop their fish from inside 1,000 yards of the target. Or at least the IJN did. From 2-3,000 yards, that gives ships a lot of time (realitively) to comb the tracks and avoid them. So anything with an effective range of 3-4,000 yards should be plenty. At least for a close in weapon.

Then there's the psychological effect for the pilot of having to fly into a storm of tracer rounds. I believe this is what is known as a significant emotional event.
 

trurle

Banned
that's along the lines of what I was thinking, along with reducing complexity and weight...

If you could get it to fire 3-400 rounds per minute and add some sort of a powered mount as well...

then what about a smaller version to put on PT boats? sort of like the three tube 20mm used on Cobra gunships? Would have played havoc as a Motor Gunboat weapon...
The technological bottleneck was mostly powered mounts. The technology for powered AA mounts was new, first adopted about 1930. The typical power available in 1940 was just few kilowatts or even fraction of kilowatt per mount, and size scaling problems were severe.
Following problems happens:
1) Rotary gun on motorized mounts will exert a significant gyroscopic forces on its mount if steered
2) To counter these forces, either counter-rotating flywheel or oversized traverse/elevation actuators are used, in both cases increasing mount weight.
2) Increased recoil due high fire rate forcing further over-sizing of mount mechanical parts

Overall, 1.1-inch Gatling (rotary) motor-steerable gun mount in 1940 will weight more, will be prone to failure, expensive, maintenance-heavy and less autonomous compared to a battery of automatic cannons of same firepower.

It is not an accident the first modern applications of Gatling (rotary) cannons (including M61) were on fixed mounts. Technology for rotary gun on motors-steerable platform was likely not practical until at least 1960, when much more lightweight and reliable motors, solid-state control circuits and stronger mechanical parts would be available.

Regarding non-motorized 1.1-inch Gatling mounts, these are definitely not manageable. Even much lighter and 1-inch automatic cannons required a heroic levels or above of physical strength to operate fast enough to track incoming aircraft, as Japanese experience with Hotchkiss-derived 25mm cannons demonstrated.

20mm manually steerable Gatling cannons around 1940 are theoretically possible, although
1) These would be short-ranged enough to only retaliate to torpedo or dive bomber which already released ordnance
2) Accuracy will be extremely marginal due gyroscopic effects, resulting together with high rate of fire in ammo shortage. I remember IOTL Japanese were limited in 25-mm mounts installation by ammunition supply, not by number of available guns. Going to have much worse ammunition shortage with rotary cannons, may be even beyond capability of more capable states like British.
 
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You know, there was a 1 inch Gatling circa 1870. They were adopted by the Army for land use and the Navy for anti-torpedo boat defense.
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in vietnam UH-1 choppers with a gunner firing a 7.7 mm gatling managed to cut a sanpan boat in two. I just can imagine the devastation brought by that much bigger weapon... cut a PT or even a Destroyer in two with one salvo...
 
The technological bottleneck was mostly powered mounts. The technology for powered AA mounts was new, first adopted about 1930. The typical power available in 1940 was just few kilowatts or even fraction of kilowatt per mount, and size scaling problems were severe.
Following problems happens:
1) Rotary gun on motorized mounts will exert a significant gyroscopic forces on its mount if steered
2) To counter these forces, either counter-rotating flywheel or oversized traverse/elevation actuators are used, in both cases increasing mount weight.
2) Increased recoil due high fire rate forcing further over-sizing of mount mechanical parts

Overall, 1.1-inch Gatling (rotary) motor-steerable gun mount in 1940 will weight more, will be prone to failure, expensive, maintenance-heavy and less autonomous compared to a battery of automatic cannons of same firepower.

It is not an accident the first modern applications of Gatling (rotary) cannons (including M61) were on fixed mounts. Technology for rotary gun on motors-steerable platform was likely not practical until at least 1960, when much more lightweight and reliable motors, solid-state control circuits and stronger mechanical parts would be available.

Regarding non-motorized 1.1-inch Gatling mounts, these are definitely not manageable. Even much lighter and 1-inch automatic cannons required a heroic levels or above of physical strength to operate fast enough to track incoming aircraft, as Japanese experience with Hotchkiss-derived 25mm cannons demonstrated.

20mm manually steerable Gatling cannons around 1940 are theoretically possible, although
1) These would be short-ranged enough to only retaliate to torpedo or dive bomber which already released ordnance
2) Accuracy will be extremely marginal due gyroscopic effects, resulting together with high rate of fire in ammo shortage. I remember IOTL Japanese were limited in 25-mm mounts installation by ammunition supply, not by number of available guns. Going to have much worse ammunition shortage with rotary cannons, may be even beyond capability of more capable states like British.

The technical know how for a robust 20mm-30mm ship based Gatling gun was not effectviely realised really before the 70s - now you might possible get something up and running before then but the previous systems such as the Bofors 40/60 and the Quad/Octol 2 pounder pom pom became realtively robust weapon systems that were hard to beat in terms of reliability and effectiveness and both had a very high ROF.
 
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