Snecma's rocket engine division has delivered its 1,000th Viking rocket engine to Arianespace. It produces three types of Viking for Ariane 4s.
Four Viking 5Cs are used to power the first stage and a single Viking 4 propels the second stage, while the Ariane 42L, 44LP and 44L are equipped with strap-on boosters powered by Viking 6s.
The first stage engine has been improved since the Ariane 1, which first flew in 1978. Ariane 2 and 3 engines had 9% higher thrust, and combustion stability was improved, in particular by replacing the unsymmetrical dimethyl monomethyl hydrazine (UDMH) fuel with UH25 (75% UDMH with 25% hydrazine hydrate). On the Ariane 4, burn time is up from 140s to 210s. The Viking was further improved with a double-wound nozzle throat, increasing reliability.
About 70 Vikings a year are manufactured.
Source: Flight International