Student's Research Could Put Lasers on Ships
By Petty Officer 1st Class Diane Jacobs
Naval Postgraduate School
MONTEREY, Calif., May 7, 1997 U.S. Navy ships may one day defend against missiles by zapping them with a laser, and a Naval Postgraduate School graduate could take some credit for this accomplishment.
Lt. Douglas Small, who earned a doctorate in physics in March, conducted research on making free-electron lasers small enough for shipboard use under the guidance of Bill Colson, who has worked with free-electron lasers for more than 20 years. Small's thesis work has allowed researchers to shorten the distance between mirrors that bounce the laser beam across the ship and into the sky.
The problem is the mirrors have to be spaced quite a distance apart to allow the laser beam to spread out because a more intense beam would "fry" the mirrors, explained Small.
"This [free-electron] laser makes a beam so small that there's no mirror on Earth we could use; it would evaporate," Colson explained. "Doug ... worked out a way the free-electron laser could be redesigned so the spot on the mirrors is much bigger; otherwise the mirrors would have to be 20 or more meters apart, and you just don't have that kind of room on a ship, "Doug worked it out so mirrors could be only 10 meters apart and still not be damaged."
By using computer simulations, Small proved his new design would work. A 100-million-volt electron beam would travel at almost the speed of light and be capable of cutting through more than 100 feet of steel in a fraction of a second, explained Colson. A prototype is in the development stage, and he believes they could be on ships early next century.
"I think it would change warfare forever as we know it," said Small. "It would make missiles obsolete. It would make an enemy think twice about launching a missile because you'd have a shield on your ship. 'If you're going to try to shoot a missile at me, I'm going to kill your missile for sure, and then I'll know exactly where you are, so I'm coming after you.'"
Small said the laser is perfect for the ship defense, especially since the Navy's changed the way it thinks in terms of fleet protection.
"It used to be that defense was thought of to protect the entire battle group, Small explained. The high-value ship would be protected first and then your ship, but now the Navy is thinking autonomous -- ship self-defense -- as single ships are sent to do missions."
So the possibility of a shipboard laser exists in a computer simulation. Where does it go from there?
"We've already proven they work and can shoot down missiles," said Small. "It's just a matter of getting Navy leadership to cough up, not just money ... but crack the missile mind set that exists."
"It took a long time to get missiles on ships," added Colson. "Historically, the Navy is fairly conservative about making serious changes. We could be a lot further in development if more effort and money were spent."
Small has already shown some military, scientific and industry leaders his work. He's given presentations in Rome, New York, at Stanford (Calif.) University and the Navy's department for directed-energy weapons programs.
Small is now assigned to the Naval Surface Warfare Center in Dahlgren, Va., where he works with the Surface Combat in the 21st Century program.
"They're thinking about direct-energy weapons in the future, and I've got the first one, with a laser being on it, so they are thinking about it. I can contribute to it. I think it's important to get these ideas on direct energy into the Navy management," said Small, who added he enjoys working with the research. "If staying in this field my entire career does that, then I'll have served my purpose."
(Petty Officer 1st Class Diane Jacobs is from the Naval Postgraduate School)