Request ACES stage/fuel depot and DTAL Lunar Lander

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http://www.nasaspaceflight.com/2009...ng-solution-via-eelv-exploration-master-plan/

The ACES (Advanced Common Evolved Stage) and DTAL (Dual Thrust Axis Lander) are part of an ambitious Lunar (and beyond) exploration proposal published by United Launch Alliance in September 2009, which is based around the Atlas V and Delta IV launch vehicles and propellant depots at LEO and L2, and doesn't require a 100t+ HLV such as Ares V or Jupiter.

ACES:

The backbone of the architecture is the ACES (Advanced Common Evolved Stage), which is currently being developed by ULA, and expected to replace the three existing cryogenic upper stages presently being used.

“Containing 41 mT of liquid hydrogen and liquid oxygen it is powered by four RL10 class engines. ACES builds on over 200 flights of Centaur and Delta, fusing technologies from both programs: sharing the Delta IV 200” tank diameter but with a common/nested intermediate bulkhead. ACES uses tank geometry, low conductivity tank structures, passive thermal protection and vapor cooling to suppress cryogenic propellant loss to boiloff,” noted the paper.

DTAL:

At the center of the lunar landing plan is the DTAL – or Dual Thrust Axis Lander. The vehicle – which lands horizontally, uses an RL10 engine to accomplish the descent deceleration to just above the lunar surface. Final landing is accomplished using thrusters mounted along the DTAL body. ULA claim this configuration places the crew and payloads safely and conveniently close to the lunar surface.

Relevant documents:
http://www.ulalaunch.com/docs/publications/AffordableExplorationArchitecture2009.pdf
http://www.ulalaunch.com/docs/publications/TheAdvancedCryogenicEvolvedStageACES2006LeBar7454.pdf
http://www.ulalaunch.com/docs/publications/DualThrustAxisLander(DTAL)2009.pdf

Other documents: http://www.ulalaunch.com/site/pages/Education_PublishedPapers.shtml