Of rocketships and paper clips
by Jeff Foust
|After reading about the X Prize while living in Hong Kong “I turned my battleship left and went for it,” Feeney said. “It had been a dream all my life to do something like this.”|
The design of da Vinci’s vehicle has changed considerably over time, and Feeney said that he has been influenced by both science fiction and aircraft design: the vehicle bears an overall resemblance to rocketships from the golden era of science fiction, while the cockpit window design is derived from that of a B-29. While much of the basic design has remained largely intact over the years, Feeney said they have taken a number of excursions, including a new design called SFORZA that could launch from the ground but carry only a single passenger. They also considered adding winglets to the basic Wild Fire design that could elevate to add stability—similar to the “feathered” mode on SpaceShipOne, but developed independently before SpaceShipOne was publicly unveiled in April 2003.
The current design, Wild Fire Mark 6, consists of two parts: a passenger capsule in the front with passive static stability and a “rocket block” that deploys aft flaps for stability during reentry. “It hearkens back to the original Vostok design,” Feeney said of the passenger capsule, “where a lot was known about aerodynamics, but there was no experience in bringing a manned rocket in from space. We wanted something that was completely passive, almost self-righting, and all the analysis that we did in the computer suggested that that this was the right approach, the simplest approach.” Both stages use parachutes and airbags for landing.
One unique aspect of da Vinci’s effort has been its reliance on a large team of volunteers to help develop and build the vehicle. Feeney said that over 600 people are part of the team. Most of them are in Canada, but there are some in the US, UK, Russia, and elsewhere. Those people have formed virtual teams, communicating by email, to work on various aspects of the project. “I’ve only ever met maybe five percent of the people in the entire project,” Feeney said.
Those volunteers have provided over 150,000 man-hours of volunteer labor to the effort, Feeney estimated. That has been crucial to the project in large part because of the difficulties the team has faced trying to raise money. He noted that when he started the effort, he estimated that he needed to raise about C$5 million (approx. US$4.2 million): a modest amount compared to what Paul Allen reportedly spent on SpaceShipOne but “we found that there had never been a five million dollar sponsorship financing in Canada ever.” The largest, he said, had been for C$3 million (US$2.5 million) for a Grand Prix race in Montreal, something far more mature and understood by potential sponsors than da Vinci’s suborbital vehicle.
|Feeney said he needed to raise C$5 million to fund the project, but “we found that there had never been a five million dollar sponsorship financing in Canada ever.”|
“At the end of the day we never got five million dollars, and never got fully funded in Canada,” he said. Through the middle of this year the team had raised just $200,000 in cash since the program’s beginning eight years ago. The development that had been done to date relied primarily on volunteer labor and in-kind donations. Those donations ranged from software to workspace for building vehicle components to a control panel from a Dash 8 aircraft, donated by Bombardier.
The project’s fortunes improved—literally—in July, when Feeney appeared at a press conference in California alongside Burt Rutan, who announced his team’s plans to fly SpaceShipOne on its X Prize flights. At that time Feeney said his team needed a half-million dollars more to complete and fly his vehicle. Over the course of just a few hours, he said, the team received four sponsorship offers, including one from the online casino GoldenPalace.com, whose offer the team accepted. The others, Feeney said, came from another online casino, the National Federation of the Blind, and “someone who was a friend of Paul Allen’s who wanted to back us simply so he could beat his friend.”
That sponsorship has eased some of the fiscal pressures on the project. Feeney said there are currently 22 people working full-time on the project, which is now based in an old hangar at Downsview Airport in Toronto. By the time Wild Fire completes its two planned test flights, Feeney estimates the project will have spent about one million dollars, plus several million dollars’ worth of in-kind donations. Had the project worked exclusively from a cash budget, without the need to solicit in-kind donations, Feeney estimates that it would have cost between $2.5 and 3 million.
The da Vinci Project’s fiscal limitations, and willingness to tackle new approaches, can best be seen in the evolution of Wild Fire’s engine, a process that Feeney, in a bit of understatement, called “interesting.” Originally the project planned to use a liquid oxygen/kerosene engine provided by Microcosm, a small aerospace company in southern California that has focused on developing expendable launch vehicles. Microcosm offered to provide not just the engine but the tanks, flight guidance system, and “the works”, according to Feeney. The problem was that this would cost over a million dollars, a price the project could not afford.
Seeking a more cost-effective solution, the project turned to a hybrid engine developed by Environmental Aeroscience Corporation (eAc) and Cesaroni Technology, an engineering company located north of Toronto. Both companies had experience developing hybrid motors, with eAc best known as one of the two finalists in the competition to build SpaceShipOne’s hybrid engine. The two companies offered a package that cost about $500,000. “Once again, we could not afford to do that,” Feeney said.
|“Unlike SpaceShipOne, which had the capital to do it their way, we had to keep it simple,” Feeney said.|
The project ended up creating a tiger team to look at alternative approaches, and over the course of four weeks designed and started work on their own hybrid engine. This engine, like other hybrids, uses nitrous oxide as liquid oxidizer, but uses paraffin rather than rubber as the engine’s solid fuel. One reason for the switch in fuels, he explained, is that it allows them to use a simpler single-port injector spray nozzle. “The focus of the program was to keep it as simple as possible,” he said. “We don’t go for peak performance: 85 percent or better in terms of performance factors, which is poor by current aerospace standards” but good enough for the project.
The result is a program that, while started just this summer, is nearly done. A ground test engine capable of generating over 57,800 newtons of thrust has been built, with test firings scheduled to begin this month. Wild Fire itself will use a larger engine that generates 80,000 newtons of thrust. Feeney noted that the team has been in contact with researchers at Stanford University who have test smaller paraffin hybrid engines; they have been “very helpful” to the project, but declined to tell the da Vinci team what additives they put in their paraffin fuel.
The engine development program has also cost just a fraction of the price of commercial hybrid or liquid propellant engines. Feeney said they have spent about US$50,000 on the engine to date. The most expensive single component was a large butterfly valve, which cost $7,000. “Unlike SpaceShipOne, which had the capital to do it their way, we had to keep it simple,” he said.
Despite deciding in the middle of this year to develop their own rocket engine, Feeney insisted that their vehicle could have been ready to fly in early October had everything gone according to plan. However, the project fell behind schedule and had to delay their launch attempt in late September. Of course, SpaceShipOne completed two successful flights by early October, winning the X Prize and taking the schedule pressure off the project.
However, Feeney said that his team is still planning on launching the vehicle later this year, if all goes well. The team’s launch insurance, which originally expired at the end of October, has been extended through the end of the year. They currently plan to perform an unmanned test flight in the third week of December from Kindersley, Saskatchewan. That would be followed by a manned flight, although he said it’s not clear yet how long it will take to turn around the vehicle for a manned flight. “Because we’re volunteer-based, as we get into the Christmas season it’s a two-edged sword: some people are extremely available, and others are not,” he said.
|“Burt [Rutan] is probably saying that he did his program for the cost of one of those NASA paper studies,” Feeney said. “Well, if that’s the case, then we’re doing ours for the cost of the paper clips to hold those studies together.”|
After the Wild Fire test flights the project plans to move ahead with a larger suborbital vehicle. Although Feeney had previously described plans for a vehicle that would be launched from an airplane, like SpaceShipOne, he has since moved in a different direction. At the conference he showed off the design of a vehicle called the Tiger Shark TS3. This eight-person vehicle would take off and land under jet power, in much the same way as Rocketplane Ltd.’s XP vehicle, using Wild Fire’s rocket engine for the suborbital portion of the flight. That vehicle could be ready to demonstrate commercial suborbital flights as early as 2006. After that, Feeney said he believes he could fly a manned orbital vehicle by 2009.
Those sounds like overly bold plans to most, but if da Vinci can successfully demonstrate its Wild Fire vehicle next month, they will show that suborbital spaceflight can be accomplished with a surprisingly modest amount of money. “I could never let a lack of money be an excuse for not getting this project done,” he said. “This vehicle is there to simply prove that it can be done… Burt [Rutan] is probably saying that he did his program for the cost of one of those NASA paper studies. Well, if that’s the case, then we’re doing ours for the cost of the paper clips to hold those studies together.”