Posted: December 2, 2007

Military lab thinks large, small to develop munitions of future

(Nanowerk News) Something about the nature of the work at the Air Force Research Laboratory Munitions Directorate can be deduced from the badges people without appropriate security clearances must wear.
The badges sport a skull and crossbones graphic with "Escort Required" printed boldly beneath.
There's no one way to characterize what the Munitions Directorate, which recently celebrated its 10th anniversary, and its several hundred employees do. They're prognosticators and theoreticians, assemblers and disassemblers, inventors and exploiters of existing technologies.
Although imagining weapons of the future is a big part of their mission, Munitions Directorate workers often handle immediate needs.
They were instrumental in fielding the "Bunker Buster" laser-guided bomb during the first Persian Gulf War and playing mind games with Saddam Hussein before the second war by dropping the nearly 11-ton "Mother of all Bombs."
Ten or 15 years ago, the emphasis at the directorate was precision hitting a target dead-on.
Today, the focus is "nano" and "bio," among other "os," says John H. Pletcher, associate director for weapons.
None of the categories are mutually exclusive. Someday, the directorate might demonstrate a nano-energetic, robo-plane based on a hummingbird's physiology that flies itself into the head of a terrorist drinking thick coffee on a balcony in Beirut, Lebanon, and then explodes.
"Nano" refers to scale. It's one-billionth of a unit. A nanometer. A nanoliter. A nanogram.
Nano-energetics relies on microscopic particles to achieve hyperefficient explosions.
The prospect of tiny granules going boom with much greater energy than now available makes it more likely that smart munitions even smaller than the Air Force's current lightweight bomb, the 250-pound-class GBU-39, will be developed.
"As we look to the future, (we ask) can we build a 10-pound-class system and can we achieve the same effect," said directorate commander Col. Kirk Kloeppel.
Achieving the same outcome might be fostered by making the entire weapon detonate. Nothing would be wasted if its wings or fins, CPU or fuses, engine or seeker somehow enhance the nanoenergetic explosion.
And maybe that weapon's design will be based on biology, or bio.
"It's us taking a look at how Mother Nature designs systems," Pletcher said of the directorate's bio-effort.
The directorate, along with outside biologists, would like to know how insects fly and see.
To figure out how to build morphing wings which would bend to change the heading and altitude of an aircraft rather than rely on ailerons, flaps, elevators and rudders it has partnered with Oxford University in England.
"We've put cameras on the backs of eagles to watch how they fly, how they maneuver," said Pletcher.
Cameras have also been strapped to Peregrine falcons, regularly called the fastest animals on Earth.
Among the researchers' goals is to determine how raptors continuously adjust their wings and tails to fly. Of particular interest is their ability to compensate for sudden wind gusts to stay on course.
The ability to sense a wind shift, process it and alter the shape of flight surfaces would be handy for a robotic, or "robo," MAV flying between skyscrapers or in mountain valleys.
Making a weapon work demands information processing.
Directorate researchers figure two-way data links would greatly enhance a machine's usefulness.
With this type of data link, a munition or some other vehicle could receive updated mission goals, including new target sets, and allow people to monitor what it's detecting and aiming for.
Communicating with a data link aboard a weapon would likely happen through radio or lasers.
The Air Force is testing lasers that can "excite molecules" at levels from causing skin discomfort to blowing apart machines. But light can also carry information.
Directorate commander Kloeppel added that lasers, whether weapons or data carriers, would be another tool in America's arsenal but would not substitute for explosives.
He also said that nanotechnology isn't a replacement for macrotechnology. Weapons would range from small to large, as indicated by the directorate's effort to build the Massive Ordnance Penetrator.
MOP is a gyroscope- and Global Positioning System-guided bomb that weighs nearly 15 tons and is 20 1/2 feet long. Its purpose is to burrow deep the maximum depth hasn't been disclosed to collapse tunnels, underground bunkers and whatever hard-to-reach, reinforced target needs to be hit.
MOP would deliver a conventional warhead packing 5,300 pounds of explosives.
Eglin Air Force Base's directorate, one of 10 in the Air Force Research Laboratory, also wants to make weaponeering the process of choosing the correct munition for a target easier.
Directorate scientists are thinking about bombs or missiles with options, including "dial-a-yield."
A bomb that could be used to hit a warehouse with one ton of blast effect or nail an enemy general inside a villa near a busy market where collateral damage must be avoided by detonating with the force of 40 pounds of explosives would be very useful. The munition would be even more helpful if its yield and fuse could be re-programmed while it's slung aboard a warplane.
Warfighters have "made it clear to us that they don't want niche weapons," said Kloeppel. "They want one weapon that can do everything."
Source: Sarasota Herald Tribune