The Lockheed Aircraft Corporation has begun production of the heat shield for the Shuttle that will transport scientists into space in the next stage of the National Aeronautics and Space Administration (NASA) space programme.
The Lockheed Aircraft Corporation has begun production of the heat shield for the Shuttle that will transport scientists into space in the next stage of the National Aeronautics and Space Administration (NASA) space programme. The work is being undertaken at the company's Palmdale plant in California.
SYNOPSIS: The heat shield is made of a unique insulating material that sheds heat so quickly that it can be held in a bare hand only seconds after being fired in an oven at intense temperatures. Even though the inside of the cube is still red hot, this technician at Lockheed can handle it without injury. The material will be used to protect passengers aboard the space shuttle when surface heat builds up as the spaceship re-enters the earth's atmosphere.
The manufacturing process begins with fibres of pure white silica, which is refined from common sand. The fibres are then mixed with water and poured into a mould. They are then pressed into a solid block and other chemicals are added under carefully controlled conditions. After being removed from the mould, the wet blocks are pushed onto a conveyor to dry. They are then cured in high-temperature ovens. After being x-rayed and checked by computer to be sure they are uniform throughout, the insulation can be cut and machined to very precise dimensions.
A coating is applied and baked on to harden the outer surface and adjust heat resistant qualities. Nearly 34,000 "tiles" of the material will be used to cover 70 per cent of each shuttle's surface. They are supplied in thousands of different shapes, sizes and thicknesses. The scientists say that the job of fitting them together on the skin of the spacecraft will be as tricky as assembling a jig-saw puzzle twice the size of a basketball court. The NASA shuttles will be reusable spacecraft, replacing conventional rockets that now fly only one mission. In all, Lockheed will supply five complete sets of insulating blocks by 1983. Each set is expected to survive at least 100 flights without replacement. The company says there is nothing like its new silica insulation and Lockheed is now investigating commercial uses for the unique material.