Composite tank could lighten load

NASA and Lockheed Martin have completed successful initial testing of the first sub-scale cryogenic tank built of a composite material that is compatible with liquid oxygen.

Lockheed Martin designed and built the composite tank, and NASA is testing it at the Marshall Space Flight Centre.

The tank has successfully completed the initial cycles of cryogenic proof testing in liquid oxygen.

In testing, the tank endured thermal and pressure environments that simulate the flight conditions a liquid oxygen tank would experience on a space launch vehicle. The tank will also undergo life cycle testing at Marshall Centre to demonstrate mission life capabilities.

‘This marks a real advance in space technology,’ said Michael Phipps, NASA project manager for this material characteristics development unit. ‘No approved standards for composite pressure vessels exist; there has not been enough information on them to write standards. So the technical data we are getting from this effort is very valuable.’

Using advanced cryogenic composite tank analysis, fabrication, and inspection techniques, the Lockheed Martin/NASA team designed and constructed the tank at both the Marshall Centre and the NASA Michoud Assembly Facility in New Orleans.

The composite tank is approximately 2.7 metres in length and 1.2 metres in diameter and weighs less than 225 kilograms, which is said to represent an 18 percent weight saving over a metal tank of similar construction.

Composites are seen as one of the key components in the drive by NASA and the aerospace industry to decrease the weight of future launch vehicles as a means of reducing the cost of launching payloads into orbit from the current $10,000 per pound to $1,000 per pound.