Andrews ETOS

American orbital launch vehicle. Proposed Earth-to-Orbit Segment booster for Andrews CEV architecture. Consisted of an Atlas V core, two Zenit-2 booster strap-ons, and a new-development LOx/LH2 upper stage.

The new expendable Lox/LH2 upper stage would require development of a new RL-X engine. The stage would be 6.5 m in diameter and 17.6 m long, with a gross mass of 283,793 kg and a dry mass of 14,402 kg. All stages would be only partially fuelled for delivery of a low-earth orbit payload of 40 metric tons, with a gross lift-off mass of 865,950 kg in that configuration.

LEO Payload: 40,000 kg (88,000 lb) to a 300 km orbit at 28.00 degrees. Payload: 22,000 kg (48,000 lb) to a translunar trajectory. Launch Price $: 240.000 million in 2005 dollars.