Yikes! ISS crew endures comms blackout during re-entry
By: William Harwood, CNET
September 16, 2011 6:33 AM PDT
A Russian Soyuz capsule carrying three of the International Space Station’s six crew members suffered an unexpected communications blackout just before plunging back into Earth’s atmosphere, completing a nail-biting descent in radio silence with repeated calls from flight controllers near Moscow going unanswered.
Finally, recovery crews spotted the Soyuz TMA-21’s braking parachute, communications with ground crews were established and the spacecraft touched down in Kazakhstan at 9:59 a.m. local time Friday (8:59 p.m. PT Thursday), tipping over on its side as it closed out an expedition lasting 164 days since launch April 4 from the Baikonur Cosmodrome.
There was no immediate explanation for the communications dropout. The repeated, unanswered calls from mission control near Moscow were eerily reminiscent of the fruitless calls to the shuttle Columbia during the orbiter’s ill-fated descent to Earth in 2003.
Engineers have traced the Soyuz-U engine failure to a kerosene fuel line blockage that disrupted the operation of a turbopump used to feed propellants to the main combustion chamber. A Russian commission investigating the failure reportedly has raised questions about quality control. But it’s not yet clear how that issue will be resolved.