Flights of fancy meet Air Force scientist

Reporting from Eglin Air Force Base, Fla. — 

Werner J.A. Dahm was strapped into the co-pilot’s seat of a B-1 bomber as it shot straight for the sky and into a paralyzing barrel roll. An expert on aerodynamics, Dahm’s mission was to determine whether the Cold War-era bomber could be outfitted with a futuristic laser beam capable of knocking out cellphone towers, disabling vehicles or destroying air defense systems.

The most pressing issue: Could airmen crammed in a tiny cockpit control the high-tech weapon during the rigors of combat flight? Dahm figured the only way to tell was to go to Dyess Air Force Base in Texas and haul his 52-year-old body into a B-1 cockpit, in the process subjecting himself to the G-force that pilots feel every time they fly.

Dahm is the chief scientist for the Air Force, and his job is to separate promising ideas from the stuff of “Star Trek.” He advises generals in an era of tightening research and development budgets which scientific innovations are worth pursuing -- or not. Weapons systems take decades to develop and accrue powerful advocates along the way. Dahm’s mission is to judge the technology early on and independent of any advocates. Sometimes it means disappointing those in charge.

The chief scientist is a participant-observer, someone who takes part in big decisions while offering an outside perspective. It combines the duties of an anthropologist and a court jester, said Mark Lewis, a University of Maryland professor and Dahm’s predecessor as chief scientist.

“The jester was the only one who could be honest with the king without getting his head lopped off,” Lewis said.

The chief scientist has only a skeletal staff and no direct authority over the service’s research labs.

“His authority is moral authority,” said Maj. Gen. Curtis M. Bedke, who oversees the labs.

After spending decades preparing primarily for confrontations with other heavily armed nations, the Air Force now must search out technologies to help not just in the conventional wars but also for low-intensity guerrilla wars and counter-terrorism strikes.

Which makes the current list of projects that Dahm is scrutinizing -- miniature drones that coordinate attacks, hypersonic flight and, one of the more promising at the moment, the laser beam -- all the more crucial.

Dahm developed a love of science, and an ability to explain it to people with little technical knowledge, at his boyhood breakfast table.

“I grew up in an environment where science was anything but scary. Shock waves at breakfast, aerodynamics at dinner,” he said.

His father had something to do with that. During World War II, Werner Karl Dahm was drafted by the German army to create an intercontinental missile capable of hitting New York from Europe. After the war, the elder Dahm was among the 130 German scientists selected to come to America to work on the U.S. rocket program.

The elder Dahm was skeptical of militaries. He initially balked when his son wanted to join the Junior ROTC program in high school because the uniforms and drills evoked the Hitler youth of Nazi Germany.

The younger Dahm attended college in Huntsville, Ala., got his doctorate at Caltech and was hired in 1985 at the University of Michigan to teach aerospace engineering. After serving for three years on the Air Force scientific advisory board, Dahm was tapped for the chief scientist’s position. He has been on the job since October 2008. If tradition holds, he probably will serve for two to three years, before returning to Michigan.

Dahm is rarely in his Pentagon office. He spends much of his time at Air Force bases and research labs around the country. The scientists welcome his visits: Dahm offers the possibility for more attention -- and more resources -- for their work.

Last year, Dahm’s research into ever smarter smart bombs, which can come within inches of a selected target, took him to Eglin Air Force Base in Florida, where researchers are working on “netted munitions,” weapons that can communicate with one another.

One version involves miniature airplanes. At a bench, a technician loaded electronics into a foot-long fuselage. In another room, a man was creating a set of small wings from carbon fiber -- a light but strong material. Across the hall, one of the planes was mounted at the center of a wind tunnel where cameras measured its aerodynamic performance.

The planes, with wingspans of 2 feet or less, resembled radio-controlled toys. But they could carry bombs and sensors that would enable them to hover over a target, waiting for the right moment to detonate their ordnance, or aborting the attack altogether.

Dahm asked technical questions about the wind tunnel and the prototype planes. He gently pushed the scientists and technicians on incorporating other technologies into their research. Dahm tries not to be heavy-handed, but he has to make sure the labs stay on the cutting edge.

One Air Force project remains particularly close to Dahm’s heart: the creation of a hypersonic aircraft engine that can fly faster than the speed of sound.

Sitting on a table in Dahm’s office is a model of the Air Force scramjet, the X-51, which looks like a missile with the nose of a shark. The scramjet works without the turbines of conventional jet engines, and instead rams air through its engine at supersonic speed.

The Air Force has been working on hypersonic engines since the early 1960s. But traveling beyond Mach 6 -- more than 4,500 mph -- poses a number of enormously difficult challenges, such as the extremely high temperatures generated.

This year, Boeing Co. and the Air Force will conduct the first of a series of scramjet flight experiments Dahm hopes will be groundbreaking. A B-52 will take off from Edwards Air Force Base, north of Los Angeles, and then launch the scramjet over the Pacific. The test is supposed to demonstrate that the jet fuel used to power the scramjet can also cool the vehicle and keep it stable.

The scramjet project was developed before Dahm arrived; his role is to explain to skeptical Air Force generals what it can do. The practical application -- at least initially -- is to create the world’s fastest cruise missile. The typical cruise missile now travels at Mach 0.8, about 600 mph. A scramjet missile should be able to travel at more than 5,000 mph.

Dahm has told Air Force generals that by striking more swiftly and from much farther away, the scramjet technology could reduce the number of bases and bombers needed, potentially a large savings.

“It takes a while to understand that this wouldn’t just do what we do today faster,” Dahm said. “We could do things differently.”

Airborne lasers for years were regarded as impractical. But the Air Force has been captivated by the laser’s capability to minimize deaths and unintended damage. As militants try to induce strikes that will kill bystanders and deepen anti-U.S. sentiment, they routinely place weapons and communications gear on mosques, schools and hospitals -- where even the smallest U.S. munition would result in civilian deaths.

“A laser is potentially game-changing,” Dahm said. “Imagine a car, in a marketplace, carrying known terrorists on their way to detonate a car bomb.

“Today, you might not strike that car because you would endanger innocents,” he continued. “But soon, you may be able to safely take the car out with a laser weapon, with no danger to bystanders.”

Over the years, military scientists have solved some of the laser’s problems: beam control, energy use and size. The laser, they think, is not sci-fi kitsch anymore.

The question that remains is how to deliver the laser to the battlefield. That’s why Dahm climbed into the B-1. The Air Force has to determine whether the airmen who enter targeting coordinates into the onboard weaponry would have enough time to operate a laser in addition to their other duties. Dahm became convinced they would.

“He’s flown the airplane, he’s asked really good questions, so that his opinion was truly, independently formed,” said Bedke, the head of Air Force research labs.

The Air Force is working to build a prototype of the laser by 2014 for the B-1. The laser would be less than 15 feet long and 8 feet wide -- far smaller and lighter than the previous generation of lasers that take up much of a Boeing 747. It would have a rotating turret that protrudes below the plane and enables the laser to hit targets in all directions.

Mounting the laser on the B-1 would be tricky because the plane flies at high speeds and was designed to hug the ground to avoid detection by radar. Flying fast and low subjects the laser’s turret to more shaking, making it more difficult to control the beam.

But if a laser can be made to work on the B-1, Dahm reasoned, it would give the service the option of installing it in the AC-130 gunship, the workhorse of the Special Operations forces.

“This is a pivotal time for the Air Force, unlike any we’ve had since we started as a service,” Dahm said. “Science and technology are changing far more quickly now than they were even 20 years ago.”

julian.barnes@latimes.com