Next month, a V-shaped airship bigger than a baseball diamond is due to rise from the West Texas desert to an altitude of 100,000 feet (30.5 kilometers), navigate by remote control, linger above the clouds and drift back to earth.
For the U.S. Air Force, the feat will demonstrate the feasibility of a new kind of semi-autonomous craft that could hover in "near space," to do reconnaissance and relay battlefield communications.
That vision is ambitious enough. But for JP Aerospace, the California-based company that built the airship for the military, the flight would represent just one more small step toward an even bigger conceptual leap: a system of floating platforms that gossamer spaceships could use as high-altitude way stations.
"The full-size station in our grand vision is 2 miles across," John Powell, the company's founder, told MSNBC.com. "But that's down the road a bit. We take baby steps."
For almost a quarter-century, Powell and his volunteer team have been working away at what he calls "the other space program." Over the next few years, he hopes to test a three-part system that could put people and payloads in orbit without rockets.
Not that Powell has anything against rockets. In fact, JP Aerospace is using small-scale rocket flights to test the equipment for the "Airship to Orbit" scheme.
"We also do some bread-and-butter work with rockets to pay the bills," he said last month in Phoenix at the Space Access '04 conference.
But if Powell's system works, it could dramatically reduce the costs associated with rocket-based launches.
Near space for low cost
The cost factor is one reason why the Air Force is interested in the first part of JP Aerospace's plan: The roughly $500,000 cost of building the 175-foot-long (53-meter-long) Ascender airship is far less than the price tag for any piloted airplane or robotic drone, said Maj. Robert Blackington of the U.S. Air Force Space Battlelab project, at Colorado's Schriever Air Force Base.
"You could probably roll about 40 of these off the line for the price of one Global Hawk," Blackington told MSNBC.com.
But the Pentagon's primary motivation is strategic rather than strictly financial. The altitudes best-suited for the helium-filled Ascender are virgin territory for the military. It could take a payload higher than any spy plane, above the weather and well beyond the reach of virtually any attack from the ground or the air.
"We've exploited [altitudes of] about 60,000 feet and below, and also low Earth orbit and above," Blackington explained. "We in the Battlelab are looking at a ‘near space’ regime. ... The technology allows us to sit in a regime that we can use now."
What would it be used for?
"We're looking at satellite-like capabilities," he said. The Ascender could loiter over, say, a suspected weapons research site and watch for trucks moving in and out — or provide a high-altitude relay for battlefield communications.
"A commander can talk with his troops on the other side of a hill or a mountain range," Blackington said.
He said the Ascender would complement a much larger military airship being developed as a separate project. Last year, the Missile Defense Agency awarded Lockheed Martin a $40 million contract to work on the High Altitude Airship, a 500-foot-long (152-meter-long) blimp, that could loiter at altitudes above 65,000 feet for as long as a year. Blackington said the HAA — which would be 25 times larger than, say, the Goodyear blimp — would be much more capable than the Ascender, but also much more expensive and somewhat more vulnerable to attack.
It will be at least a couple of years before such airships float over battlefields. The objective for next month's Ascender test is merely to demonstrate that the unmanned airship can safely reach the 100,000-foot level, respond to commands beamed up from the ground to navigate between two points, loiter in position for five minutes, then come down safely.
The window of opportunity extends from June 7 to 21 at the Pecos County/West Texas Spaceport at Fort Stockton, but the liftoff is dependent on the weather.
"We actually had the first flight window in February, but we sat there and stared at 30-knot West Texas winds for two weeks, so we're going back in June," Powell said.
The demonstration would mark the end of the project's first phase, and the Air Force would then decide whether to go on to the second phase. Phase 2 would likely call for developing an Ascender craft capable of flying a five-day mission by the end of 2005, Blackington said.
Next ... the final frontier
The Ascender is just the first leg in JP Aerospace's three-legged race to space. Powell and his team of almost 50 volunteers are also working on two other balloon-based craft that go beyond the bounds of the current Air Force program: a high-altitude platform dubbed the "Dark Sky Station," and a 6,000-foot-long (1.8-kilometer-long) Orbital Ascender that would travel from the station to orbit.
In Powell's scheme, piloted Ascenders would sail up to a Dark Sky Station at an altitude of 100,000 to 140,000 feet (30 to 42 kilometers). "It supplies literally a space station, but not in space. It's parked at the edge of space, as a permanent manned facility," he explained.
Small-scale tests have already been conducted with balloons rising to the 130,000-foot level. In the next 18 months, Powell foresees sending a two-person crew to a 100-foot-wide (30-meter-wide) station at an altitude of 30,000 feet (9 kilometers). The first missions would last only three hours or so, but as the stations grew, they would be staffed for longer periods.
Over time, permanent stations would be buoyed by mile-long cells sheathed in tough composite material and filled with helium. The electrical power could come at first from fuel cells, and later from solar-cell material sprayed on the station's surfaces. Powell speculated that the stations could drift slowly with the thin air currents around Earth's polar regions. At that altitude, the outside temperature would be about 130 degrees below zero Fahrenheit (-90 degrees Celsius).
Getting to orbit
Like the military Ascenders, the stations could serve as remotely operated telecommunication relays. But Powell also sees them as construction facilities and way stations for the third and least-tested part of his space program, the Orbital Ascender. This craft would look like the atmospheric Ascender, only much bigger and lighter, with a few extra twists.
"What if you flatten it out and give it a little bit of aerodynamic shape, and point it up a little bit so you have some of that thrust turned into lift?" Powell asked. "As you climb up, your drag is dropping, and now you're accelerating. The question comes, can you get aerodynamically clean enough, while still supporting the lift enough to slowly get faster and faster ... to get all the way to orbit? Is there a drag-power combination to do that? We think there is. It looks like there's a wide margin."
The three-part trip to orbit is aimed at getting around the fact that one helium-filled craft could never make the whole trip: Any balloon strong enough to weather the trip up to 100,000 feet could never be made light enough to go higher.
To achieve orbital flight, the craft would require a spaceworthy propulsion system — something more substantial than helium and propellers. Powell would turn to the type of continuous-thrust ion propulsion system used on NASA's Deep Space 1 and the European Space Agency's SMART 1 moon probe. Based on computer simulations with different configurations, he contends that such engines could drive the mega-balloon to orbit in three to nine days.
Powell intends to conduct an ion engine test at an altitude of 100,000 feet by the end of this year.
As the timeline stretches toward its latter stages, the details get fuzzier: Can JP Aerospace, which is pursuing the problem on a pay-as-you-go basis, get enough helium to fill miles-long balloons and keep them replenished? Could such a craft really attain the Mach 25 velocity required for orbital flight? How would the Orbital Ascender deal with micrometeoroids and the other inclement weather that takes place outside Earth's atmosphere? How would JP Aerospace's tests be regulated?
"We're working on a regular aircraft certification," Powell said, "which is a big bear, and it's expensive, but it's known."
Powell projected that the system could be spaceworthy in seven years — depending on how the testing and the fund-raising efforts go. For now, he is just concentrating on one baby step after another. And even if there's a misstep along the way, Powell believes his unconventional approach to spaceflight provides a far wider safety margin than the "tried-and-true" methods.
"Say you're on the shuttle, and you're screaming up to orbit, and something goes wrong. You have about a tenth of a second to discover the problem and fix the problem, or you lose the crew," he observed. "Here, something goes wrong — complete power failure. Well, calm down. You're floating up here, you start drifting down, you have a meeting or two, you have some engineers walk down and work on the thing. ‘OK, we can't fix it — come on down.’ ... You've taken the danger out of space travel."