Atlas 3A vehicle data
Posted: May 14, 2000
The Atlas 3A is a two-stage rocket capable to lifting payloads of 4,060 kg (8,950 lb) into a geostationary transfer orbit. It features no strap-on solid rocket boosters and is the most powerful version of the Atlas family currently available.
Atlas is the name of a family of booster stages. Centaur is a family of high-energy, restartable upper stages. Atlas 3 is the designation for an Atlas 3 stage with a booster engine and a Centaur 3 upper stage.
The Atlas 2A is a two-and-one-half stage launch vehicle. The Centaur upper stage is mounted on top of the one-and-one-half stage Atlas booster.
Atlas booster propulsion is provided by the RD AMROSS RD-180 engine system, which consists of two thrust chambers fed by a common turbopump assembly. The engine is ignited before liftoff and develops a total sea-level-rated thrust of 617,500 pounds. The interstage adapter connects the Atlas to the Centaur. This aluminum structure provides the structural link between Atlas and Centaur. The Atlas is separated from the Centaur by a flexible linear-shaped charge system attached to the forward ring of the interstage adapter.
Centaur Upper Stage
The Centaur propulsion system uses one RL10A-4-1B engines with an extendible nozzle manufactured by Pratt & Whitney. The engine has a rated thrust of 22,300 pounds. The Centaur engine is restartable and is capable of multiple firings in space, separated by coast phases.
The stub adapter and equipment module are attached to the forward end of the Centaur. The stub adapter is bolted to the forward ring of the Centaur tank and supports the equipment module and payload fairing. The equipment module attaches to the forward ring of the stub adapter and provides for mounting of the Centaur avionics and the spacecraft adapter.
The fairing provides thermal and acoustic enclosures for the payload and launch vehicle electronic compartments during prelaunch and ascent. Portions of the external surface of the fairing are insulated with cork to limit temperatures to acceptable levels. Noncontaminating thermal control coatings are used on internal surfaces to reduce incident heat fluxes to the spacecraft. The payload fairing is jettisoned eight seconds after Centaur Main Engine Start 1.
While coasting in the transfer orbit, the Centaur issues separation commands to release and separate the spacecraft from the forward adapter.
Flight data file
Vehicle: Atlas 3A (AC-201)
Payload: Eutelsat's W4
Launch date: May 24, 2000
Launch window: 2139-2358 GMT (5:39-7:58 p.m. EDT)
Launch site: SLC-36B, Cape Canaveral, Fla.
Launch preview - Read our story for a complete preview of the first Atlas 3A launch.
Launch timeline - Chart with times and descriptions of events to occur during the launch.
The RD-180 - Facts and figures about the Russian-built engine to power Atlas 3.
Eutelsat W4 - Description of the satellite to be launched on AC-201.
Launch windows - Available windows for future launch dates of AC-201.
Watch the planned sequence of events as the inaugural Atlas 3A rocket carries the Eutelsat W4 telecommunications satellite into orbit.
PLAY (775k, 2min 39sec QuickTime file)
Learn about the engines and stages of the Lockheed Martin Atlas 3A rocket that will launch the Eutelsat W4 satellite.
PLAY (342k, 49sec QuickTime file)
Download QuickTime 4 software to view this file.
MISSION STATUS CENTER