Snecma's rocket engine division in Vernon has delivered its 1,000th Viking rocket engine to Arianespace, the company announced at the show.

Snecma produces three types of Viking engine for the Ariane 4 fleet of launchers.

Four Viking 5C engines are used to power the first stage, one Viking 4 propels the second stage, while the Ariane 42L, 44LP and 44L versions are equipped with strap-on boosters powered by the Viking 6 engines.

The first-stage engine has been improved since the Ariane 1, which first flew in 1978. The engines on Ariane 2 and 3s had 9% higher thrust and combustion stability was improved, in particular by replacing the UDMH (unsymmetrical dimethyl monomethyl hydrazine) fuel with UH25 (75% UDMH with 25% hydrazine hydrate).

On the Ariane 4, the burn time was increased from 140 to 210s. Later the Viking featured a double-wound nozzle throat that increased reliability.

Once a year an engine from the production line is subjected to a very long duration test lasting 50% longer than nominal flight time, to ensure that no discrepancies have occurred in the production line.

Source: Flight Daily News