Forum: Technology

I'll avoid the issue of whether the 5th gen should have guns here. (IMO no).

What I'm interested in is the differences in aircraft guns.

It seems that a 30mm single barrel gun is close to ideal in terms of weight, firepower etc.

So why do we end up with the rotary guns and the other calibers?

The rotary gun has more weight and volume and needs electricity from the plane. It also takes time to spool up.

In the A-10 the ROF is lowered to 2100 rpm anyway. Why not use 2 Oerlikon KCA's?

I wonder why the F-35 uses the 25mm gun when the BK 27 and the Rafale's gun seem superior.

The you have the Russian gun GSh 30-1 at about half the weight although it is said that this gun only lasts 2000 rounds.

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shingen wrote:

So why do we end up with the rotary guns and the other calibers?

The rotary gun has more weight and volume and needs electricity from the plane. It also takes time to spool up.

1) 6 barrels vs. 1 equals less barrel wear and trauma to the airframe, even with the higher ROF. Yeah...the airframe buzzes but it's not like a MiG's big bore, single-barrel cannon that would actually slow the jet down when ya pulled the trigger.

2) In days of yore when pilots smoked unfiltered Chesterfields, wore silk scarves, turning fights were the norm, and turn rates didn't get much over 5G, you could get away with using a single barrel gun or multiple guns to get X-amount of rounds on the target. In a modern turning fight with modern fighters turning harder, faster, and with more maneuverability, the higher ROF is needed to get a lethal amount of rounds in the target zone for the oh-so-brief instant the pipper is on the bandit. And the spool-up time is on the order of milliseconds. Not a big deal.

I worked on the M230 single-barrel chain gun on Apache helicopters. While it was an AMAZINGLY effective gun for close air support, it vibrated the hell out of the airframe. In fact, so much that it would break things like the landing search light, the sighting system in the nose (TADS/PNVS) and jar loose circuit cards in the various black boxes which were only a few feet away. It seemed every time the gun was fired at least something broke. Older guys who used to work on the AH-1F Cobra, which has a 3 barreled derivative of the M61 found on most modern US fighters never complained about this. They only complained about the feed system. The Marines still use that same gun (the M197) in to this day in their AH-1W and AH-1Z aircraft. All the times we did training with the Marines, we never heard them complain that their gun screwed the aircraft up. That's the beauty of a multi-barrel system.

discofishing wrote:

I worked on the M230 single-barrel chain gun on Apache helicopters. While it was an AMAZINGLY effective gun for close air support, it vibrated the hell out of the airframe. In fact, so much that it would break things like the landing search light, the sighting system in the nose (TADS/PNVS) and jar loose circuit cards in the various black boxes which were only a few feet away. It seemed every time the gun was fired at least something broke. Older guys who used to work on the AH-1F Cobra, which has a 3 barreled derivative of the M61 found on most modern US fighters never complained about this. They only complained about the feed system. The Marines still use that same gun (the M197) in to this day in their AH-1W and AH-1Z aircraft. All the times we did training with the Marines, we never heard them complain that their gun screwed the aircraft up. That's the beauty of a multi-barrel system.

"Was"? Did they switch it out for something else?

Not sure what you're asking about. The Apache still uses the 30mm M230 gun similar to the Bushmaster design. The Cobras use the nothing but the M197 three barreled 20mm cannon as far as I know. Interesting enough, there are gun pods of various caliber that are capable of being mounded on hard points on both aircraft. I think this was mainly used on Cobras in Vietnam as the used to strafing runs much like the fixed wing aircraft did.

http://en.wikipedia.org/wiki/U.S._aircraft_gun_pods Wikipedia can give you an idea of what gun pods where used on various airframes.

Forum: Technology

Irrelevant Topic? Aircraft Gun Comparison