USAF Launch Supersonic Bomb Firing Technology

coondoggie writes "Boeing and the US Air Force today said they have tested new technology that for the first time will let military aircraft launch bombs from aircraft moving at supersonic speeds. Researchers from Boeing Phantom Works and the Air Force Research Laboratory used a rocket sled in combination with what researchers called "active flow control" to successfully release a smart bomb known as MK-82 Joint Direct Attack Munition Standard Test Vehicle (JDAM) at a speed of about Mach 2 from a weapons bay with a size approximating that of the U.S. Air Force B-1 bomber, Boeing said. Active flow control is a tandem array of microjets upstream of the weapons bay that, when fired reduces the unsteady pressures inside the bay and modifies the flow outside to ensure the JDAM munition travels out of the bay correctly."

Re:Very very incorrect.

[tjstork]

The F-22 can not 'cruise' at Mach 2. That would be even more buck rogers than the aircraft is already.

Actually, the big poop is that, in fact, it probably can. I've read that the engines on that thing are so powerful that with afterburner the aircraft would be capable of Mach 3 but the airframe simply isn't strong enough to take it, so the flight control software intentionally limits the speed so the plane doesn't break up. It's a very aerodynamic design coupled to a fantastically powerful engine, and the result is that the F-22 is quite a burner. One has to wonder if there might be a covert block with a stronger airframe for reconaissance.

Re:Very very incorrect.

[jafiwam]

Rumor has it some laser guided bombs were filled with cement and used as k-kill devices during the last Iraq war to take out tanks next to civilian targets.

At sub-orbital re-entry speeds, you don't need an explosive to fark up a tank. And if you can hit it reliably you don't need to go boom, it just shatters because a big block of stuff just came through the top, out the bottom and into the dirt below.

Re:Very very incorrect.

[Runefox]

Actually, it's not structural, it's more the fact that the air inlets are fixed rather than variable, so the engines can't get the optimal amount of air intake at different flight envelopes. Because of this, pushing the aircraft beyond mach 2.0 for any extended period of time will cause structural failures in the air intake. Presumably, this is a feature designed either to increase stealthiness or decrease overall weight and/or surface area, or perhaps to optimize air intake for supercruise. I'm not a flight engineer or rocket scientist, only an aircraft buff, so I can't really say.

Well

[Sycraft-fu]

Please remember that military spending isn't without benefit. Often technologies are developed there that then later become useful for civilians that are just the kind of thing you aren't likely to see developed on the commercial market.

Best example is GPS. No way a company was going to build something like that. Even a government wouldn't do that for civilian reasons. However the military felt it was worth it. Out of that we now have an awesome navigation system used the world over, and finally because of its success there IS interest in building a civilian system in Europe (though it is not going well).

While military spending isn't what one would call the best use of money, let's not pretend like it is a black hole that nothing comes out of. There are an amazing amount of technologies that are directly owed to the military (trauma surgery would be another, the Internet yet another).

Also there's just the sad truth that there are assholes in the world and nations have a need for defense. Don't think for a second North Korea would be nearly so well behaved if South Korea just disarmed their allies all left.

You're quite mistaken..

[caveat]

Capt. John Stapp withstood a 46.2G decceleration [ejectionsite.com] when his rocket sled going 632 mph plowed into a water brake. His eyeballs were completely filled with blood, but cleared overnight.

They don't do it like they used to

Re: bomb accuracy in WWII

[CodeShark]

Not 100% true in terms of WWII history, at least in some places. High altitude bombing was never very effective, but the naval bombers in the Pacific theater got very very good at hitting their targets with less civilian casualties. How do I know? Because I lived in Japan for two years about thirty years ago, and once had friends nearby who took me to the site of an old, bombed out munitions factory that was completely surrounded by really really old Japanese houses and a nearby religious temple. I was told by WWII generation Japanese people that lived there that the day the factory was bombed was quite amazing because sometimes they would see the "little planes" come in at really quite bizarre angles to literally pitch their bombs past the temples, etc. into the factory area only.

Their kindness towards me is probably the highest compliment that I can give a military flyer -- the so called enemy noticing that the American's weren't out to kill all of them, and describing it to a youngster like me that wasn't even there, 30+ years after the fact.