That's One More Step Backward From Mars
Methane dropped from CEV plans, NASASpaceFlight.com
NASA Drops Requirement For Methane Engine From CEV, Aviationnow.com
“…The new document also drops requirements for a LOX/methane engine on the CEV service module as a placeholder for future extraction of the fuel from the atmosphere of Mars, and for delivery of unpressurized cargo to the International Space Station …”
White House Space Policy: A Renewed Spirit of Discovery
“The fundamental goal of this vision is to advance U.S. scientific, security, and economic interests through a robust space exploration program. In support of this goal, the United States will: … Extend human presence across the solar system, starting with a human return to the Moon by the year 2020, in preparation for human exploration of Mars and other destinations;”
“Develop and demonstrate power generation, propulsion, life support, and other key capabilities required to support more distant, more capable, and/or longer duration human and robotic exploration of Mars and other destinations; and Conduct human expeditions to Mars after acquiring adequate knowledge about the planet using robotic missions and after successfully demonstrating sustained human exploration missions to the Moon.”
Editor’s update: Once again, under Mike Griffin, the implementation of the VSE shrinks further back from sending humans to Mars – via the moon – a goal NASA was directed to pursue by the President two years ago tomorrow.
15. Architecture Advantages, ESAS Final Report
“Use of pressure-fed Liquid Oxygen (LOX)/methane propulsion on the CEV SM and Lunar Surface Access Module (LSAM) ascent stage enables In-Situ Resource Utilization (ISRU) for lunar and Mars applications and improves the safety of the LSAM;”
13. Summary and Recommendations, ESAS Final Report
“An integrated pressure-fed LOX/methane service propulsion system/Reaction Control System (RCS) is recommended for the SM. Selection of this propellant combination was based on performance and commonality with the ascent propulsion system on the Lunar Surface Access Module (LSAM). The risk associated with this type of propulsion system for a lunar mission can be substantially reduced by developing the system early and flying it to the ISS. There is high risk in developing a LOX/methane propulsion system by 2011, but development schedules for this type of propulsion system have been studied and are in the range of hypergolic systems.”
8. Risk and Reliability, ESAS Final Report
“The additional performance benefit of a mature LOX/methane system, along with the choice of a pump-fed LOX/hydrogen engine for LSAM descent, provided the launch mass capability to enable the 1.5-launch architecture, thus allowing for crew launch on the single-stick SRB, which has the lowest LOC probability. The LOX/methane system was also desirable to eliminate the operability issues related to hypergols and to enable the use of in-situ methane on Mars and oxygen on the Moon and Mars.”
“8.1.1 LOX/Methane Engine/RCS Development The development of the LOX/methane engine was recognized as one of the largest architectural risks during the course of the ESAS. No LOX/methane engine has had any flight test experience and there has been only a limited number of Russian ground tests. The LOX/ methane system was desirable from a performance perspective and also to eliminate the operability issues related to hypergols and to enable the use of in-situ methane on Mars and oxygen on the Moon and Mars.”
NASA News Conference With Mike Griffin: Exploration Systems Architecture Study (Transcript)
“So, the really only difference is the addition of the LOX/methane system that’s baseline for the CEV service module and for the lunar ascent. The LOX/methane combination offers quite a lot more performance capability than the storables that you were talking about in your question with, we believe, no additional risk. In fact, overall, we think the system will be safer.
We will be carrying as a backup in the program the use of hypergolic propellants on the service module and on the lunar ascent stage such that, if the LOX-methane technology development does not work out as we expect, we will have a system that will work, although of course, it will provide lesser performance than what we’re talking about today.”
