With the world’s second personally funded human space flight under way, questions have surfaced about a mysterious malfunction during the landing of the last flight, one year ago. Something went wrong with the spacecraft guidance system, subjecting the three space travelers to higher than expected G-forces when they hit Earth’s atmosphere.
If not fixed, a similar problem on a future flight might turn out to be even more hazardous. “You could at least miss the touchdown point,” noted Dennis Newkirk, author of the Almanac of Soviet Manned Space Flight and owner of an Internet Web site on Russian space technology. “Or you could end up not coming home at all — really bad news.”
There’s no sign that last year’s malfunction threatened California millionaire Dennis Tito, the world’s first paying space tourist, or the two Russian cosmonauts beside him in the Soyuz spacecraft. But the event has been wrapped in secrecy and conflicting reports that may have been designed to deflect blame for the error.
MSNBC.com has obtained documents that attribute the problem to errors made by Russian controllers at their Mission Control Center in Moscow. However, attempts to confirm this assessment have met with no cooperation from officials associated with the international space station program.
The Soyuz craft came down from the station last May at the conclusion of the first “taxi mission” to service the international space station. Such a trip that has to be made every six months to replace the station’s old emergency bail-out capsule with a new one. The Russians and Tito delivered a new Soyuz to the station, then rode the old one back down to Earth a week later.
A similar taxi mission, funded by the French space agency and bearing a French astronaut as well as two Russians, took place last October. By all accounts, that trip went smoothly from start to finish.
On Thursday, the station’s third taxi mission launched South African millionaire Mark Shuttleworth to the station, along with Russian cosmonaut Yuri Gidzenko and Italian astronaut Roberto Vittori. Like Tito, Shuttleworth is said to be paying about $20 million for the flight — cash that the Russians sorely need to keep their space program in business.
Detailed in documents
The problems with the Soyuz re-entry a year ago were not mentioned in the public reports issued by Russian and American officials — but they are detailed in internal space agency documents obtained by MSNBC.com. Instead of enduring the expected deceleration of about 4.8 G’s, or 4.8 times the force of Earth surface gravity, Tito and his two Russian shipmates experienced forces of nearly 7 G’s.
This was still within the range of predicted “contingency” cases, but for the 60-year-old Tito and his marginal medical status, it added a measurable additional hazard to his health.
Tito has described his flight at many public events, and he includes the “overloads.” Speaking to a space convention in Washington in January, he explained the problem as being due to some generalized “human error.”
In contrast, the rumor among some NASA astronauts was that the flight crew had “screwed up,” a point of view that coincided with the general disdain that professional astronauts often express privately toward nonprofessional “tourists.”
“The crew was celebrating the departure from the station a little too enthusiastically,” one NASA astronaut told MSNBC.com last August. “They missed the first of two audio cues to arm the rocket burn, and when they heard the second, they thought it was the first and did not push the correct button until it was far too late.”
When the Soyuz computer autopilot sensed that the spacecraft was hitting Earth’s atmosphere “long,” or farther downrange than expected, it compensated for the overshoot by diving more steeply. This brought it back toward its planned touchdown point, but also elevated the deceleration forces.
Questions at NASA
According to the documents obtained by MSNBC.com, NASA officials first asked about the problem at a teleconference on Nov. 5, six months after the landing. They asked the Russians about the higher G-loads and “some error in the landing location,” and what was being done to prevent it from happening again. Senior Russian official Vladimir Utkin acknowledged there had been an “irregularity.”
A month later, a senior Russian official told another NASA panel that Russian experts had been distracted by an unrelated equipment malfunction during the docking of Tito’s Soyuz, a week earlier. Consequently, the official said, Russian flight controllers did not have time to prepare a full set of steering commands for the return journey.
As a result, the Soyuz guidance system was pointed somewhat away from the intended orientation. The rocket burn for returning to Earth was performed on time, but slightly off-center. So the Soyuz was slowed less than planned, and it flew farther before it entered the upper atmosphere.
The Soyuz autopilot compensated for this overshoot by diving more deeply, just as in the earlier blame-the-flight-crew version of the “irregularity.”
“This does seem to have been an unusual situation,” said space historian Newkirk. The most recent similar incident occurred in 1979, when a two-man Soyuz experienced a problem with the deorbit burn and consequently felt more than 10 G’s of entry force. According to Newkirk’s book, the failure was considered so serious that the Soviets then made an unmanned flight test of the Soyuz to validate the fixes.
More questions raised
The new explanation of last year’s problem raises more questions than the first version. When the crew was blamed, at least they had the planned ignition time in their logbooks and could recognize a failure by using their watches. But if the steering commands are faulty for a future Soyuz re-entry, the crew would have no way of detecting it and making a manual correction.
If the pointing error had been just twice as large, the resulting off-course descent path could have led to serious trouble. Deceleration and heating could have risen over planned limits, or the spacecraft could have landed thousands of miles downrange, in Siberia or the northern Pacific Ocean.
Attempts to obtain information on the problems through official channels have so far failed: A Freedom of Information Act request for these reports was filed Feb. 23, but NASA did not respond to the request within the statutory 20 working days. Further inquiries as to when an answer could be expected have not yet been answered.
An inquiry with the Public Affairs Office at the Johnson Space Center in Houston, NASA’s lead center for the space station program, received the reply that the space agency would not comment on the incident. Requests made to Energia, the Russian company that builds and operates Soyuz space vehicles, went unanswered.
James Oberg is a former NASA engineer and space journalist whose latest book, “Star-Crossed Orbits,” chronicles the course of U.S.-Russian space cooperation and the international space station effort.