The first crewed re-entry since the Columbia accident, the 4 May return of the sixth International Space Station (ISS) crew in Soyuz TMA-1, did not go exactly as planned. The craft landed north of the Aral Sea, in Kazakhstan, 285 miles (460km) south-west of the prime landing site after a steeper-than-planned re-entry.

Forces on the three-man crew exceeded the maximum 7g planned - possibly reaching 13g. In a normal re-entry, angle of attack is controlled automatically or manually to use the atmosphere as a brake and reduce g forces.

According to crew reports, the computer shifted suddenly from a normal re-entry to a steeper ballistic path. The only way to change the re-entry manually is to press a button, which is guarded against inadvertent engagement.

It was the first landing by the TMA craft, which has improved avionics, and the first Soyuz landing with NASA astronauts on board. Soyuz automatic landings are usually accurate, but some earlier flights made similar ballistic re-entries.

The two-man seventh ISS crew, launched on Soyuz TMA-2 on 26 April, has taken over operation of the space station. They will remain on board until October, when they will be replaced by another two-man crew.

Source: Flight International