Pica shield passes test

Boeing has delivered what it says is the largest ablative heat shield ever constructed for a spacecraft.

It has been made for NASA's Orion crew exploration vehicle to protect astronauts from extreme heat during re-entry into Earth's atmosphere.

The contract to deliver a thermal protection system manufacturing demonstration unit was awarded to Boeing Advanced Systems by NASA Ames Research Centre last year. It forms part of NASA's Constellation programme.

The work on the 5m-wide heat shield was carried out at Boeing's Huntington Beach, California facilities and the Ames team accepted it last month.

This month, it was transported to NASA's Kennedy Space Centre in Florida for additional inspection.

The shield is made from phenolic impregnated carbon ablator (Pica), which is being considered for Orion's heat shield as it has already been used successfully in the heat shield of NASA's Stardust spacecraft.

It consists of an integrated concept made up of multiple Pica components. Each piece is significantly larger than typical space shuttle tiles. Boeing claims this greatly reduces parts and component complexity.

'Our manufacturing demo-nstration unit met NASA's advanced development prog-ramme risk-reduction objectives to move the Orion heat-shield programme toward full-scale development,' said Thomas Andrews, Boeing thermal protection system programme manager.