Two consecutive chaotic and dangerous landings by Soyuz space capsules, including one with an American astronaut aboard, have NASA and space experts concerned about the spacecraft's reliability in ferrying astronauts to and from the international space station.
The worries are compounded by the fact that starting in 2010, when the space shuttle fleet will be retired, the United States will be entirely dependent on Russia's Soyuz capsules and rockets for transporting all astronauts and most cargo to the station -- until at least 2015.
The Soyuz has been a remarkably safe and reliable spacecraft for four decades, and the recent failures do not appear to have anything to do with new technology or new procedures. Rather, the two very similar reentry failures point to malfunctioning parts or faulty workmanship, space experts say.
"These are the same kinds of warning signs that occurred on the shuttles before the Columbia accident but were ignored," said James Oberg, a former NASA mission control specialist and now a media consultant on NASA developments. He recently wrote an article on the Soyuz problem for the magazine IEEE Spectrum based on, among other sources, internal NASA documents related to Soyuz.
"We're asking a lot of the Russians -- a doubling of their Soyuz production -- and we may well be overstraining their capacity," he said.
Recovery site on April 19, 2008
The Russian-made Soyuz capsule touched down at 4:51 a.m. Eastern time about 260 miles off target, the spokesman said, which was highly unusual given how precisely engineers plan for such landings. It was also about 20 minutes later than scheduled.
Officials said the craft followed a so-called ballistic re-entry — a very steep trajectory that subjects the crew to extreme physical force. Mr. Lyndin said the crew had experienced gravitational forces up to 10 times those on Earth during the descent.
Congress has decided to start asking questions about the safety review of the Russian program:
Sen. Bill Nelson (D-Fla.) has asked NASA whether Americans will be on the investigative commission and, if not, whether they can be added. Nelson said he has not yet received an answer.
"This is very worrisome, and makes it all the more important to get new American spacecraft ready to fly sooner than 2015," he said. Nelson and his colleagues in the House and Senate have sought an additional $2 billion over two years to speed design and production of NASA's new Orion and Ares systems -- which are being built to service the space station and carry astronauts to the moon and beyond-- but the White House has not supported the additional spending.
Adding to the concern, three usually dependable Russian Proton rockets, used to send satellites into orbit, have also failed in the past two years.
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The United States has entered into a $719 million contract with the Russians for crew and cargo transport services to the space station from 2007 to 2011, and is now negotiating a second long-term transport contract.
The Russian company that makes the Soyuz, the Korolev Rocket and Space Corp. Energia in Moscow, is having difficulty attracting and retaining skilled aerospace workers, a problem that has been widely discussed and lamented in Russia. The company has historically produced four or five single-use Soyuz capsules a year, but it now must manufacture nine or 10 a year to make up for the 2010 retirement of the U.S. space shuttle fleet.
Soyuz Capsule Diagram
Oberg says that there is good cause to worry about the safety of the Russian space program in light of the April 19 incident:
A Russian source first broke these stories onto the news wires. 'It was very lucky that all members of the crew survived,' an unnamed space engineer told Interfax. ?Everything could have ended much worse. It was a very narrow escape.'
He provided additional technical details that enhanced his credibility. 'As a result of excessive thermal overloads, the hatch was significantly burnt. Besides, the transmitter antenna melted and the contact was lost. The exterior part of the pressure equalization valve was burnt,' he continued.
The significance of the failure alarmed him, he explained: 'Judging by the fact that the contingency situation occurred again, it is clear that the technological discipline in preparing space equipment for flights is declining,' he concluded. 'There is no guarantee that the crew of the next Soyuz capsule landing six months from now will not face the same problems.'
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