Soyuz TMA-10 docked to the ISS on April 9, 2007 at 22:10
UTC, following two days of free flight. Its two Russian crew members remained on the station until the spacecraft's return to Earth in October 2007. Spaceflight participant
Charles Simonyi returned to Earth aboard
Soyuz TMA-9 on April 21, following eleven days of ISS handover operations. TMA-10 undocked from the ISS at 07:14 UTC on October 21, and deorbit occurred at 09:47. During
atmospheric re-entry, the spacecraft transitioned to a
ballistic reentry, resulting in it landing west of
Arkalyk, approximately northwest of the intended
Kazakhstan landing site. The trajectory was reported by the crew as soon as they came out of the
communications blackout caused by plasma surrounding the spacecraft. (A ballistic trajectory is a backup re-entry mode that takes over if something fails during normal re-entry.) A Commission of Inquiry determined that the ballistic re-entry was caused by damage to a cable in the spacecraft's control panel, which connected to the control panel with the Soyuz descent equipment. Landing occurred at 10:36 GMT. A ballistic trajectory entry had happened previously, with the
Soyuz TMA-1 mission that returned
Expedition 6. The information about the failure of a connector in service panel was faulty. In actuality, the Service module (PAO) had failed to separate from the re-entry module (SA), and the ship had entered the atmosphere with the opposite orientation. Explosive bolts in connection struts between the Re-entry module and the Service module had failed to explode. The heat had melted the failed struts and the re-entry module had separated from the service module - the changed trajectory of the ship had caused the switch to a ballistic emergency landing. The same situation had happened during the Soyuz 5 mission in 1969. The Soyuz re-entry module was, and still is, protected on all sides with thermal insulation, so the struts melted before the crew entry hatch was damaged or destroyed, thus saving the crew. The Russians kept the failure of the Soyuz TMA-10 a secret until it happened again on the Soyuz TMA-11 with a NASA astronaut on board. This infuriated NASA (the Commission of Inquiry had lied to them) and this led to further investigation as well as special EVA activity on the ISS to check the docked Soyuz TMA-12 and its explosive bolts in their connection struts. == References ==