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January 31, 2005

I may be ugly, but...

Anybody remember the movie Blazing Saddles? Of course you do. Well, there's a scene where Alex Karras' character Mongo ("...just pawn in Great Game of Life...") doesn't like the way a horse is looking at him and decks the animal with one punch. Mongo is, of course, a fraction of the the horse's size and weight, but nevertheless slowly and relentlessly plods up to him, cocks his fist and BAM!...horsie go to sleep.

When I saw that again after several years in the Hog, I thought, "What a superb analogy. 'I may not be the prettiest thing you've ever seen on the battlefield, and it might take me awhile to get to the fight, but don't even THINK about letting me connect if we ever go toe to toe.'"

So John sends me this clip from Montieth, one of our more frequent and always-interesting reader/commentors. (Note: PLEASE Right Click and Save As to keep the bandwidth use under control)

OK...a couple of things. Yes, it's impressive but here's a couple of things to consider when you watch...

- The HEI round has about as much explosive content as the soldier's hand grenade, except that it's going about 3200 feet per second and 70 of them exit the barrels in your general direction every second (after the first second of firing and the the gun has reached it's full rotation speed).
- "General direction" is, actually, a misleading term. The gun has a mil dispersion of 5. In English, that means that at one thousand feet 80% of the bullets remain inside a 5-foot circle. As range increases, that circle widens in an essentially linear way--at 2K, 10 feet; 3K 15 feet; 5K; 25 feet. Sound like a lot? Imagine the assault platoon you're facing being able to throw, simultaneously, 70 hand grenades at you from a mile away and getting them all to land in the space of your mess tent...and when they hit they're somewhere north of supersonic.
- The GE/Philco-Ford cannon they came out of has, roughly, 6 billion moving parts. OK, maybe not 6 billion, but more than, say, your car's engine. So what. Wellllll...when I pull the trigger, the gun goes from a standing start to 3900 RPM in just under 1 second and fires from the barrel directly in line with the jet's fuselage centerline. When I release said trigger, the gun spins down to zero, reverses, counts the empty shells in the seven-barrel breech assembly until it senses a live round, and stops when the breech is reset with the next live round is in the firing barrel...in 1.5 seconds. Next time you go for a drive, stop in the driveway and rev her up to 3900 RPM. See if you can do it in a second...then shut it down and see how long it takes to stop (much less reverse the crankshaft rotation)...it'll probably take longer than a second-and-a-half. OK, I don't expect you to try to give your car engine whiplash (our visitors usually aren't DemocraticUnderground types), but you get my drift.
- Did I mention the thrust rearward the gun generates? 18,000lbs. With both engines producing about the same amount of thrust (which is why it takes us so long to get to the fight), well, thank God for physics...it keeps us airborne.
- The gun is loaded with special equipment that attaches to the front underside of the forward fuselage...we call it the dragon...and belts/links are not used. The bullets are fed into the system and carried along a conveyor that goes into the back of the ammo drum. The rounds are held by a groove in their cartridge bases on a helix assembly the corkscrews through the drum; the tips of the bullets are pointed at the center of the drum and when they reach the front of the drum are picked up and fed into the breech assembly as individual rounds. They travel through the firing sequence, are pulled from the barrel and placed back on the conveyor to travel back to the rear of the ammo drum and back into the helix. Elegant, closed-loop, beltless system.
- Of course, when the thing breaks it's freakin' spectacular. No, it doesn't explode, but the sudden stop of a mechanical jam can really screw up all that metal. Fortunately, most failures are in the electronic control system. When the jet senses the unload/recock process didn't work right (took too long(!), post-firing bullet count was off, etc.) you'll get a "Gun Unsafe" light in the cockpit. You play it safe and bring it back IAW emergency procedures but usually it turns out to be a bad chip or whatever. In the 20+ years I flew the jet, I can't remember a serious mechanical failure...and I think I would.

...and one last thing...
The GAU-8/A is NOT a Vulcan...it is the Avenger. To equate the two would be like equating a 9mm with a .44 magnum.

So there you have it...my 2 cents. Thanks again to Monteith and now John will get off my a$$...or not.

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