The recent abort, and eventual successful launch, of the Space-X mission to resupply the space station is one of many bumps in the road to commercial space. One should not expect the road to be smooth, or that replacing a Russian supply system with over a half century and almost 1,000 missions in its heritage […]
The recent abort, and eventual successful launch, of the Space-X mission to resupply the space station is one of many bumps in the road to commercial space. One should not expect the road to be smooth, or that replacing a Russian supply system with over a half century and almost 1,000 missions in its heritage will be easy. While we all hope that the commercial efforts of such companies as Space-X and Orbital Science Corporation will succeed, we also know many problems will arise.
According to Ed Keith, an ATI teacher of rocket and missile design and technology, the NASA commercial space road is a major step in the right direction. On the other hand, he sees many bumps along that same road. Historically, American launch vehicles have been developed and operated with large government budgets. New commercial ventures have an incentive to do the same type of missions at much lower cost. This means that some short cuts are made, some new risks are accepted, and new ways of doing business are employed.
In Mr. Keith’s three day class on
Fundamentals of Rockets and Missiles, the questions of commercial versus government design standards are compared. The apparent effect is that a commercial rocket DDT&E (Design, Development, Test & Evaluation) effort, like the Space-X Falcon, should cost about one-fifth of what a government DDT&E program costs for a comparable sized rocket. This cost difference is documented in some cost models or
Cost Estimation Relationships (CER). These same cost models fail to explain why any but commercials should be chosen. Mr. Keith’s explanation is that the shortcuts have one major impact; lower initial reliability. Indeed, the first three launch attempts of the Space-X Falcon-1 launch vehicles all failed. Since then, there have been two successful launches of the Falcon-1 and three successful launches of the much larger Falcon-9. Commercial space ventures have the opportunity to take calculated risk short cuts that government programs are mandated to avoid, and the business incentive to make wiser trade-offs and choices.
This does not mean that the road to commercial space will be smooth from here on in. A more realistic expectation is for the road to be bumpy. Space-X has had five successful launches in a row, but their proven historical reliability is five successes in eight tries, or 62.5% reliability. The best we can say regarding the Falcon-9 rocket is that we can be confident it is at least 75% reliable at this time. If, or when, a Falcon-9 rocket fails in the future, it should be considered a bump on the way to commercial space, not a failure of this new way of doing business.
Even this latest successful launch cannot be counted as a victory for commercial space until the Dragon Space Capsule successfully docks with the Space Station. While the launch is the most risky six minutes of the mission, Space-X still must get the craft safely to a docking port with all the cargo intact. The difficulty and risks of rendezvous and docking of a spacecraft to the Space Station should not be underestimated.
There will always be critics of commercial space who will look for negative occurrences to undermine commercial style ventures. There is also a high probability that a number of future commercial space missions will include embarrassing failures. The criteria for success in commercial space should not be whether the road is bumpy with occasional failures. The success criteria should be whether access to space is better, faster and cheaper using commercial methods and incentives than is practical with the type of government bureaucratic methods and incentives that have dominated the final frontier for the past half century.
Dr. Tom Logsdon teaches
Orbital Mechanics and
Global Positioning Satellite technology classes for ATI. His colleague, Edward L Keith, teaches
Fundamentals of Rockets and Missiles,
Space Mission Analysis and Design and other rocket related classes for ATI. These instructors are available to reporters who need more information. Contact ATI at 410-956-8805.
The Soyuz TMA-06M spacecraft docked at the space station’s rooftop after a two-day orbital chase. Riding on the Soyuz were American astronaut Kevin Ford of NASA and Russian cosmonauts Oleg Novitskiy and Evgeny Tarelkin, who are beginning a five-month mission to the space station.
“We can see you, everything looks fine,” Russian cosmonaut Yuri Malenchenko, who was already onboard the station, told the approaching crew before the two spacecraft docked about 230 miles (370 km) over southern Ukraine.
Ford, Novitskiy and Tarelkin launched into space on Tuesday (Oct. 23) atop a Soyuz rocket that blasted off from the Central Asian spaceport of Baikonur Cosmodrome in Kazakhstan. They are the second half of the space station’s six-person Expedition 33 crew, which is commanded by NASA astronaut Sunita Williams. Malenchenko and Japanese astronaut Akihiko Hoshide round out the crew.
The Soyuz spacecraft is bringing some fishy friends to the space station in addition to its human crew. The spacecraft is ferrying 32 small medaka fish to the space station so they can be placed inside a tank, called the Aquatic Habitat, for an experiment to study how fish adapt to weightlessness.
Thursday’s Soyuz docking at the space station kicks off a flurry of arrivals and departures at the International Space Station.
A robotic Dragon space capsule built by the private spaceflight company SpaceX will depart the space station on Sunday (Oct. 28) and splash down in the Pacific Ocean off the coast of Southern California. The Dragon capsule will return nearly 2,000 pounds (907 kilograms) of science experiment hardware and other gear back to Earth.
On Wednesday (Oct. 31), an unmanned Russian Progress spacecraft will launch toward the space station and arrive six hours later to make a Halloween delivery of food, equipment and other Halloween treats.
Williams, Hoshide and Malenchenko are in the final weeks of their mission to the space station, and will return to Earth Nov. 12. At that time, Ford will take command of the space station crew to begin the Expedition 34 mission.
Space Exploration Technologies, better known as SpaceX, has announced plans to launch its Falcon 9 rocket and Dragon spacecraft on 7 May.
SpaceX had originally planned to launch the spacecraft next week, but it postponed the launch to give engineers more time to complete preflight testing and analysis. According to the company, the launch is set for 6:38am PT, weather permitting, at Cape Canaveral Air Force Station in Florida.
If all goes well, SpaceX’s spacecraft will be the first privately built and funded spacecraft to rendezvous with the International Space Station. The goal is for SpaceX to conduct regular commercial cargo missions to the space station.
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