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Acceptance of Alma Telescope

10 March 2009

On 6 February 2009, the first North American Alma telescope was accepted at the Joint Alma Observatory.

The 12-meter-diameter antenna is the first of twenty-five being provided by North America’s ALMA partners, whose efforts are led by the National Radio Astronomy Observatory (NRAO)

Airborne Composites manufactures the carbon fibre composite structures for these antennas, under a 6 year contract for Vertex Antennentechnik of Duisburg, Germany. Airborne supplies the reflector Back-Up Structure (BUS) that consists of 24 segments, the centre hub that connects the segments, the Quadrapod truss structure that supports the sub-reflector and the head-part that connects the 4 quadrapod legs. The structure consists of carbon fibre - aluminium honeycomb sandwich, made from high stiffness pitch carbon fibre. The design is optimised for stiffness and thermal stability, with a ultra-low coefficient of thermal expansion (CTE). This ensures that the high precision of the reflector surface is kept under all wind and temperature conditions.

10 antennas have already been supplied by Airborne to Vertex Antennentechnik, with a production rate of 1 antenna per 5 weeks. This high production rate is achieved by a dedicated production line, a fully industrialised production process with optimised tooling concepts, and thorough quality assurance procedures. The project is supported by the Investment for Growth program of Airborne with recent installation of 2 prepreg cutting machines, Fibersim software, laser projection and a 5-axis milling machine of 7 x 3.5 m.

Alma, the Atacama Large Millimeter/submillimeter Array, is a gathering armada of short-wavelength radio telescopes whose combined power will enable astronomers to probe with unprecedented sharpness phenomena and regions that are beyond the reach of visible-light telescopes. The observatory is being assembled high in the Chilean Andes by a global partnership between East Asia, Europe and North America in cooperation with the Republic of Chile.