I'm sad that the AF wants to retire this plane. This plane was defined with one purpose: build a plane around this gun, that being a 30mm autocannon firing depleted uranium shells (not radioactive) that fires at such a rate that it retards the velocity of the plane carrying the gun, and would melt the gun if it fired from full to empty continuously.

The plane was built for survivability. It can withstand an engine being shot off (why the engines are external on "pods"). The cockpit is (I think) surrounded by a 2 inch titanium tub.

I'm not sure the JSF, i.e. F-35 will be capable of taking over this role, as is intended.

As a side note, depleted uranium is certainly still radioactive. "Depleted" refers to the percentage of U-235, the isotope used for making nuclear weapons. Only about 0.7% of naturally occurring uranium is U-235, with the rest being mainly U-238. U-238 emits alpha particles, with a half life of about 4 billion years.

The radioactivity is unrelated to its use as bullets, which relies on its high density, but it is radioactive.

I am told the gun is also quite good at shooting ground troops. A relative of mine had an A-10 stay with his group most of the night. Every time the enemy decided to go after them the A-10 came back and made them rethink their actions.

That zipper noise: To think that those are 30mm rounds being fired at that speed is just plain scary. http://www.xdtalk.com/attachments/img_7014-jpg.34438/

If one of those is lingering, I wouldn't even fight if I was the enemy.

It might not be able to kill a modern main battle tank, but I bet spraying it with rounds like that would fuck it up pretty seriously.

The A-10 delivers rounds at a rate that the individual shots are indistinguishable to the the human ear.

Another story that I've heard is that a B-1 flying at operational altitude (200 ft above ground level, mach 2) was often as effective as dropping munitions.

> Another story that I've heard is that a B-1 flying at operational altitude (200 ft above ground level, mach 2) was often as effective as dropping munitions.

That very topic is being discussed right now on the Aviation Stack Exchange: http://aviation.stackexchange.com/questions/35771/is-it-corr...

The B-1 can not even reach Mach 1 at such a lot altitude. It's maximal operating velocity (at any altitude) is Mach 1.25.

People tend to really underestimate how much harder it is to go faster once you reach 0.90 or so, especially at low altitudes.

It's also going to present zero obstacle to a meteorite travelling at six times the speed of sound. It'll rip through that armor like it's not even there.

Mach 6 is a heck of a slow meteorite.

But the if a small meteorite (only a few grams) were traveling that slow, 1.5 inches of titanium would do quite a bit.

I'm not sure how fast these go once they hit the atmosphere. I've seen numbers in the 15 to 25km/hr range, which is pretty damned fast, but how much do they slow down in the thicker atmosphere closer to the ground?

15 to 25km/hr is a running speed of human, probably you meant 15 to 25 km/s here (actually, some meteorites hit atmosphere >70km/s). Seems like they decelerate pretty fast after that[0]:

"At some point, usually between 15 to 20 km (9-12 miles or 48,000-63,000 feet) altitude, the meteoroid remnants will decelerate to the point that the ablation process stops, and visible light is no longer generated. This occurs at a speed of about 2-4 km/sec (4500-9000 mph). From that point onward, the stones will rapidly decelerate further until they are falling at their terminal velocity, which will generally be somewhere between 0.1 and 0.2 km/sec (200 mph to 400 mph). Moving at these rapid speeds, the meteorite(s) will be essentially invisible during this final “dark flight” portion of their fall."

0. http://www.amsmeteors.org/fireballs/faqf/

> 15 to 25km/hr

just btw, 25 km/s is almost 100.000 km/h.

That depends on the size. Smaller ones just never make it to the ground - take a look at this table:

https://en.wikipedia.org/wiki/Impact_event#Airbursts

One they get big enough, they slow down from ludicrously fast to still ludicrously fast. The smallest impactor shown in that table enters at 17 km/s, loses 90% of its energy traversing the atmosphere and smacks the ground at nearly 5km/s. You'll probably want to take your titanium armour and stand somewhere else.

We took a couple of minutes off this afternoon to watch some Warthogs pulling some tight maneuvers... to think, USAF wants to sell them all to Poland...