Helios 2B is a French military high-resolution optical imaging reconnaissance satellite. The high-resolution camera provides an ultra-stable platform for high definition and infrared optical images for day and night coverage. It will collect medium-resolution images across a wide footprint for cartography applications, according to the French defence ministry.
Helios 2B was one of the primary payloads of the Ariane 5 launched from Kourou Space Centre. The Cargo Fan Assembly was used to cool the battery packs of this satellite.
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 Cargo Fan Assembly