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It amazes me that anyone thought this Airacucumber would actually go 300 MPH. Fat Albert personified.
The engineers apparently didn't consider boundary layer.
Are we talking flight instrument gyros here, or some sort of fire control system? Remember, Jimmy Doolittle's instrument flying escapades were relatively recent history, and the technology was still in the development and tweaking phase.Given that the gyroscopic system was based on an anti-aircraft gunnery platform: What kind of gyro did it use?
Fully functional remote control turrets were still nearly a decade in the future. I suspect the only viable option might've been fixed forward firing cannons as in conventional fighters of the time.Was it possible to have produced a gyroscopic gun-sighting system with the technology of the time of the aircraft's development to the pre-production stage that could have allowed the system to be operated with simply the pilot alone?
I think we might have had the conceptual knowledge. Whether that would translate easily into reliable hardware is another question entirely. When I went to work at GE, the trash bins were littered with the detritus of failed iterations of feed mechanisms for the Vulcan cannon and Minigun. Every new application required a reengineered feed mechanism, and every new feed mechanism developed it's own unforeseen catastrophes. When feedpath turning sprockets start punching holes in 20MM cartridge cases and spraying propellant around next to a gun firing 6,000 rounds/minute, it makes a mess. The insides of the test range firing stand shelter huts looked like war zones.The two gunners could operate the guns as a backup, but their primary role was to feed belts of 37mm rounds into the cannon: Was there any need for this? Did we have the knowledge in the United States to produce a feeding system that would have allowed the full ammunition capacity intended without the need for multiple belts to be fed into the cannon without jamming?
Fire-control system: It was used for controlling the guns. While I could be wrong, the turrets were generally controlled from the cockpit, but as a backup, could be controlled from the nacelles.Are we talking flight instrument gyros here, or some sort of fire control system?
Was this gyro a gimbal system? Was there ever serious issues with the matter of tumbling the gyro?MIFlyer said:I would assume that any control system for the 37MM guns on the Airacuda was similar to that used on ships, where the gyro platform defined "Level" and adjusted the guns to compensate for the rocking of the ship. You would see the guns moving up and down before they fired and in reality that was the barrel remaining "level" while the ship moved under it. This same approach was adopted for tank guns. Our tanks did not have to stop to fire but could fire on the move even as the tank pitched and rolled over rough terrain.
If this was based on a shipboard artillery stabilizing gyro, I would expect it to have those issues. The range of motion of a fighter plane is a bit broader than that of a battleship. OTOH, the Airacucumber looks more like a battleship of the sky than a fighter plane, so maybe not an issue. The early 50s gyros in our club's T34 would tumble at the drop of a hat if you exceeded 60° in roll or 30° in pitch and forgot to cage them.Was this gyro a gimbal system? Was there ever serious issues with the matter of tumbling the gyro?
Perhaps the ones at Bell and North American did not, but those at NACA did. Of course, a few years later engineers at NA didn't notice NACA and Robert T. Jones work on swept wings, so one does wonder...The engineers apparently didn't consider boundary layer.
If you think about it a bit, the answer becomes obvious. Rate gyros (aircraft rate of turn instrument) rely on the gyroscopic property of precession, while the integrating type utilize the property of rigidity in space. Now which do you think would more useful in providing a stable platform for aerial gunnery?
Given that you used the term "stable platform for aerial gunnery", I'm guessing integrating type.If you think about it a bit, the answer becomes obvious. Rate gyros (aircraft rate of turn instrument) rely on the gyroscopic property of precession, while the integrating type utilize the property of rigidity in space. Now which do you think would more useful in providing a stable platform for aerial gunnery?