In Thrust We Trust
To Tim Pickens, rockets are the only way to go.
- By Peter Garrison
- Air & Space magazine, July 2007
It probably never occurred to Wernher von Braun that salami could be a rocket fuel. But it occurred to Tim Pickens. “We used a drill bit to bore a hole in the center, and lit it with a Fourth of July sparkler,” he recalls. The aroma reminded Pickens of being at the state fair, and he fed what was left of the fuel to his cat.
For a guy who plays a leading role in the push toward commercial access to space, Tim Pickens has garnered a lot of publicity for goofy stunts. There was the rocket canoe, actually a Pickens-assisted project of Tim’s friend Glen May, who produced 70 pounds of thrust using two small engines and rolled-up notebook paper for fuel. The canoe would hiss along at 20 knots or so, trailing a plume of dirty purple smoke, for as long as the fuel held up—not long enough to get May into trouble, or even to the middle of a small lake.
More fraught with peril was the rocket backpack Pickens built, then sold to an adventurous airline pilot before getting to fly it himself. During one tethered test the throttle got stuck and the contraption tossed the poor pilot around like a rodeo rider. Miraculously, he was not hurt. Pickens is still tinkering with that design.
There’s the rocket pickup truck, a cobalt-blue Chevy SS with a rocket engine bolted to the bed and “In Thrust We Trust” emblazoned on the bumper.
Then of course there’s the rocket bicycle. Popular Mechanics magazine awarded it a Breakthrough Award in 2005, triggering a flurry of copycat press coverage. Pickens and his daughter Sarah, for whom he had originally built a “cold” carbon-dioxide-powered rocket bike when she was 10, found their way onto Comedy Central’s “The Daily Show.” It was hard to tell from the interview, during which Jason Jones suggested that a rocket bicycle would be a great way to get around on Mars, whether the deadpan Pickens was in on the joke or the butt of it.
To Pickens himself, the silly stunts have a serious purpose. “It’s not about trying to break the land speed record,” he says. “It’s just going 20 or 30 mph down the road and feeling that acceleration and saying ‘Wow, this is cool!’ If you can’t do something real once in a while, you’re just running tests and looking at data, and it’s way over there and it’s 500 feet away. You could be an expert and never fly, and say, ‘I’ll tell you how to do it.’ I want to do stuff, make it happen.”
Pickens’ gift as an engineer is, in fact, exactly that: making it happen, often in ingeniously simple and primitive ways. People already know how to get to space. “We’ve got all this data, we’ve got all this knowledge, but we still don’t have a commercially viable, affordable launch system,” he laments. “Right now it could cost from 15 to 20 thousand dollars a pound to get something into orbit. Affordable would be a quarter of that.” His goal is to bridge that gap.
Pickens was born in the rocket town of Huntsville, Alabama, in 1964, the last of six children. His father was, like him, a talented technician who had naturally drifted into engineering. While working on a degree in physics he taught ground support and electronics at the Army’s Redstone Arsenal in Huntsville. Later he worked for NASA on the inertial navigation system for the Saturn V moon rocket. Except for what he calls four “dark years” during which the family moved to his mother’s hometown, Jackson, Tennessee—compared to Huntsville, a technological wasteland—Tim grew up in the shadow of NASA’s Marshall Space Flight Center, among the engineers and scientists who were sending larger and larger payloads farther and farther into space. But he was by inclination a hobbyist, not a professional engineer. When he earned a college degree, it was not in physics but in business.
His secret love was rockets, however, and he read about themcompulsively, sucking in knowledge from far and wide, whether it was Rocket Propulsion Elements by Sutton and Biblarz or articles in popular magazines. Personal passion sometimes enables a spellbound amateur to surpass a bored professional. Pickens was mixing black powder before he was 10, and had designed and built a rocket motor at 12. By the time he was 16 he already counted a hang glider, a hovercraft, and an airboat among his engineering accomplishments.
In 1994 Pickens became involved in the efforts of HAL5—the Huntsville chapter of the grassroots National Space Society—to build the first privately funded rocket to reach an altitude of 50 miles. He learned about the project at a chapter meeting. “They were talking about putting a roach, or whatever they could, in space, and they had a little money. They had like $10,000,” Pickens recalls. “I thought, ‘This is really cool!’ ” He approached the program’s director, Greg Allison, an engineer who had worked for several NASA contractors. Allison quickly recognized “innate capability” in the shy, 30-year-old Pickens, who at the time worked for an equipment rental company. He was a master machinist and a resourceful scrounger who “could look in a garbage can and come up with a rocket,” says Allison. The practical-minded Pickens was a breath of fresh air in a field where, Allison says, “there are a lot of people who are really good at flying viewgraphs and PowerPoint presentations.”
HAL5 was largely populated with technical types who longed to escape the stultifying rocket bureaucracy: engineers who wanted to make a difference, idealistic engineering students eager to take what they were learning in school and apply it in the real world. Few of them, however, had Pickens’ special combination of theoretical knowledge and mechanical experience.
It was Pickens who proposed using hybrid rather than solid rocket motors (see “The Right Fuel for the Right Rocket,” p. 62), meaning that the engine would combine liquid and solid propellants. And he suggested using as a fuel asphalt rather than the conventional—but much more expensive and harder to handle—hydroxyl-terminated polybutadiene, or HTPB. The asphalt idea wasn’t new with Pickens; he had gotten it from reading about an eccentric rocket pioneer named Jack Parsons, an early principal at NASA’s Jet Propulsion Laboratory in Pasadena, California, who practiced black magic in his spare time. Eventually Parsons blew himself up while conducting backyard experiments, but not before he had demonstrated that ordinary paving asphalt was a pretty good rocket fuel.
Working on HAL5’s HALO project, an acronym for high-altitude lift-off, Pickens recalls, “I knew that asphalt has a real low heat of vaporization, which means that you can easily heat it a little and get an ignitable vapor. You can pour it, you can cast it, and it’s $17 for 100 pounds. Everybody laughed. I said, ‘Okay, let’s just test it.’ Turned out it had as good a performance as the HTPB. But with the HTPB you had to mix the hardener, you had to do vacuum casting—it was just a pain in the rear.”
Against advice from professional engineers, project director Allison decided to go the hybrid route for the HALO vehicle. “So we were going to use asphalt and laughing gas,” Pickens relates. “We said, ‘We’re going to pave the way to space, and we’re going to laugh all the way.’ ”
Pickens, who ended up in charge of HALO’s propulsion system, assembled the motor from inexpensive components. For the oxidizer tank, he joined two donated aluminum fire extinguisher bottles, neck to neck. Drilling and tapping a hole in the bottom of one tank, he screwed directly into it the motor assembly: a cylinder of hand-wound graphite-epoxy with the fuel “grain” cast inside and the control valve and injectors at one end. The recovery parachute nestled in the depression between the two oxidizer tanks. Avionics and cameras perched on the nose of the rocket, under a conical cap. The rocket, enclosed in a wooden trusswork gondola, was to be carried to 100,000 feet beneath a helium-filled balloon. On firing, it would shoot up through the balloon on its way to space. The launching system—called a rockoon—was an old one that had been used for scientific sounding rockets in the early 1950s. Pickens nicknamed the team the “rockoon buffoons.”
He built test stands and associated equipment, and would eventually log more than 300 static firings of the HALO motor. In March 1997, the group launched its rockoon from a beach in North Carolina. Unfortunately, the balloon split open before reaching its peak altitude, and the rocket, hastily fired from a vertical position as it fell, attained an altitude later calculated to have been 36 miles. As often happens with rocket development, the failure had its up side. The HALO rockoon reached the highest altitude ever for an amateur-built rocket, earning it an entry in the Guinness Book of Records.
A year earlier, Allison and Pickens had founded the High Altitude Research Corporation, and one of its early projects was to go after the CATS (Cheap Access To Space) prize, offered by the Space Frontier Foundation for the first amateur-built rocket to lift a two-kilogram (4.5-pound) payload to an altitude of 200 kilometers (124 miles). The team’s entry—“HALO on steroids,” Allison calls it—blew itself apart 100,000 feet over the Gulf of Mexico in 2000, only days before the $250,000 CATS prize expired unclaimed.
It wasn’t long, though, before Pickens had another project to work on, for even higher stakes.
In 1999, Burt Rutan, who had launched his aeronautical engineering career 25 years earlier with an arresting series of canard designs for amateur airplane builders, came to Huntsville to speak to a chapter of the Experimental Aircraft Association. The visit had an ulterior motive; Rutan was scouting companies involved in rocket propulsion because he wanted to compete for the X Prize, a $10 million award awaiting anyone who could launch a reusable passenger vehicle into space twice within two weeks.
“You know, I’m getting bored with flying,” Pickens recalls Rutan announcing to the homebuilders (which must have been like Jesus saying to the apostles, “I’m getting tired of religion”).
“I’m really thinking about rocketships,” Rutan said. “I’ve looked at solid [fuel]s, I’ve looked at liquids, I’m looking at all options. If there are any rocket people out there who can steer me….” Rutan had been talking to the big players in industry—Aerojet and Thiokol—and both had offered existing engines. They even offered to send out guys in spacesuits to fuel it. “Spacesuits?” Rutan said. “We’re not even going to have spacesuits inside the ship!”
After the meeting, Pickens introduced himself. “I’m really concerned,” he said. “If you go to the big guys, you’re gonna lose your shirt. And you ain’t never gonna come out of the woods.”
They talked at length, and Rutan, himself a maverick engineering prodigy, discerned in Pickens the same capability that had struck Greg Allison. Pickens convinced Rutan that he could make the X Prize motor happen. Returning to his company, Scaled Composites, in Mojave, California, Rutan gathered his team in a conference room for a working lunch and announced, “I’ve found the guy who’s going to put us in space.” He then played a video of the rocket bike and the rocket canoe. One Scaled engineer remembers the incredulous reaction. “ ‘Burt,’ everybody says, ‘you have lost your mind!’ ”
At that point it was still not a foregone conclusion that the engine for Rutan’s spaceship would be a hybrid. For a year the e-mails flew back and forth between him and Pickens, who was still only an unpaid advisor. In 2001 Rutan, having pared an initial list of 21 possible rocket engine suppliers down to six or seven, visited Space America, a now-defunct Huntsville-based company for which Pickens was then working. Space America intended to build a launch system for putting small payloads into orbit and had built a 12,000-pound-thrust regeneratively cooled liquid-fuel engine. But something unexpected happened during the presentation for Rutan. The wrong video somehow found its way into the VCR, and rather than a successful test firing Rutan was treated to the dramatic spectacle of the liquid engine blowing itself to smithereens. “Whoa!” Rutan exclaimed. “There went my crew.”
“That hosed it for liquid [fuel]s,” says Pickens, laughing.
Rutan, a fanatic for simple systems that use as few parts as possible, was looking for a “bolt-in” propulsion system like the manufactured engines he used on his airplanes. But he was finally won over by Pickens’ arguments for hybrids, even though the choice meant designing an engine from scratch and making a new one for each flight. Rutan was willing to accept those penalties, along with the reduced performance of a hybrid motor, in exchange for tossing out all the tricky plumbing and valves and hassle that liquid oxygen required, not to mention reducing the risk of an explosion like the one he’d seen on the videotape.
According to Rutan, Scaled came up with the concept for SpaceShipOne’s motor and designed, built, and tested its main components, including a massive flange on the tank and motor case from which the motor was cantilevered. Scaled also built the nozzle and the carbon-wound fuel casing. Only a few internal components, including the injector, igniters, and motor controllers, were outsourced, because Scaled had no experience in those areas. Rutan got a couple of small companies, eAc of Miami and SpaceDev of San Diego, to build and test the subsystems. “We did not have full confidence that any small shop could do an adequate job with these components,” he says, so Scaled awarded two contracts, “hoping that at least one would work.” Ultimately, SpaceShipOne included hardware from both SpaceDev and eAc on its historic test flights. (SpaceDev founder Jim Benson tells a different story, and is still arguing with Rutan over who should get credit for the vehicle’s propulsion system.)
Pickens finally went to work for Scaled Composites in 2002, with the title Propulsion Lead Engineer, or, as he likes to put it, Herder of Cats. He remained at the Mojave headquarters for a year before returning to Huntsville and his wife Melanie and their daughter Sarah. “He chose his family over his career,” Rutan says with a slightly disapproving tone. Pickens puts it differently. “A country boy from Huntsville, we just don’t go off and chase too big of dreams. You gotta eat mama’s cooking at night, you know what I mean?”
But Pickens’ year designing the engine for SpaceShipOne at Mojave had been decisive for the project. He was, test pilot Mike Melvill recalls, Rutan’s “golden boy.” And his thinking permeated every detail of the engine. The common bulkhead between oxidizer tank and motor, which had been a basic design feature of the HALO and CATS rockets, became a key element of SpaceShipOne’s design, one that Rutan patented. Without Pickens, Melvill thinks, SpaceShipOne might not have worked.
A year after leaving Scaled, Pickens did something unexpected: Under the aegis of the corporation he had formed with Allison, he entered the X Prize race himself. He called his project Liberator. It was a conventional single-stage, liquid-fuel rocket, about two-thirds the size of the Huntsville-made Redstones that had lofted America’s first satellites into orbit in 1958. “I’m sitting at home with a lot of rocket hardware—engines and tanks and valves and stuff,” recalls Pickens. “I had one 12,000-pound-thrust regeneratively cooled kerosene-LOX [liquid oxygen] engine, and parts for another. And I’m thinking: I could do a mission like this.”
The crew capsule was a tall metal tube in which the occupants sat one above the other. It was not for the claustrophobic, but the X Prize did not stipulate that the passengers be comfortable, nor that anyone but the pilot be on board for the test flights—just that the vehicle had to have enough room to seat three people.
It was very late in the game, but despite having worked at Scaled for a year—or perhaps because he had—Pickens had doubts about Rutan’s vehicle. At the time its key technologies, especially the idea of folding the wings to increase drag during reentry, had not yet been tested at supersonic speed. To Pickens’ knowledge, there had been no wind tunnel work; all of the aerodynamic analysis of the SpaceShipOne design had been done on a desktop computer, and for fun, the early flight simulations were run on X-Plane, a $70 home entertainment program for airplane buffs. “There were performance issues,” Pickens recalls. “We figured SpaceShipOne would probably slide—who knows what can happen, we can’t worry about them, let’s move forward.”
Instead of Rutan’s plan to drop his vehicle from another airplane, “I was banking on a traditional rocketry approach,” says Pickens. “Ocean landing. I’d done ocean launches with the NASA barge program and also the HALO program. We definitely were in the right town with the right talent pool. In my opinion we were certainly one of the two or three most technically competent teams.”
The showstopper turned out to be not technology but money. “Boy,” laughs Pickens, “did I learn a lot about reality. Somebody might want to give you $10,000, but if he’s only got $100,000 to start with he’s gonna annoy you just as much as somebody who had 10 million dollars and gives you a million.”
Liberator didn’t have time to turn into a full-fledged debacle, because Scaled won the Ansari X Prize in 2004. “In the last months they pulled a lot of rabbits out of their hats,” says Pickens. But Rutan’s former employee had learned a precious lesson. “I realized my business is not gonna be based on selling rides. I’m gonna sell shovels to the miners.”
Selling shovels to the miners means doing what he’s always done best: putting together practical rockets and related hardware such as test stands, using existing, robust, proven technologies. He set up a new company, Orion Propulsion, borrowing the name from his father, who had started a telecommunications test equipment business called Orion in 1982. Orion Propulsion has already become a small but steady player in a field where startups come and go at a dizzying rate. In its second year of business, the company had 11 employees and revenues of more than $2 million, and had landed several NASA contracts and subcontracts. If another big contract comes through this year, the company will add about 30 employees; Orion is on a Boeing-led team bidding to build the upper stage for NASA’s new Ares 1 crew launcher. The company’s most ambitious current project is Responder, a multi-stage rocket designed to put up small satellites—five kilograms or so—at low cost and on short notice. The project will be funded by Orion and a consortium of government partners.
Responder’s engine is not a hybrid. “Orbital [space travel] is an order of magnitude harder than suborbital,” Pickens observes, and that’s where the difference in propulsion systems comes into play. Fuel efficiency is not critical for suborbital tourist vehicles like Rutan’s; instead, reliability and safety are paramount. For the much more difficult task of lofting payloads to low Earth orbit, hybrid engines are significantly less efficient than the time-honored pairing of kerosene and liquid oxygen.
The project demands all of Pickens’ ingenuity and everything he’s learned in his dozen meteoric years in the rocket business. “You ask yourself: What can I do to support the industry without sticking my neck way out? And that’s how we’ve come back to ‘Well, we can do propulsion, do testing, and we can do ground support,’ ” he says. “Right now the company doesn’t have any debts. We made a profit last year and this year. It’s working. And I think it’s really gonna work once NASA’s budget is turned on. Because at the end of the day, somebody’s gotta build ’em.” And somehow, you know Tim Pickens will be right there among the somebodies.