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Griffin's Vision For Apollo 2.5
Honolulu HI (SPX) Feb 14, 2006
In a previous column I criticised the return-to-the-moon plan presented by the ESAS study group as too grandiose and too expensive, and promised to show how it could be "simplified and de-porked enough to fit inside the budget wedge that is likely to be available".
Since I wrote that, NASA Administrator Mike Griffin has already started that process without any advice from me. Just look at the list of changes that have been made already:
No Methane Engines
This feature of the plan was only a sop to the Zubrinistas that was certain to be dropped as soon as the Mars Society was on record supporting the plan. The only rationale for this engine was in-situ propellant generation from the atmosphere of Mars. It was totally unneccessary for ISS or Moon mission.
This fuel combination was also politically difficult. The only way a methane engine could be developed in time for the Block 1 CEV was to turn the whole project over to Russia, the only place where a methane engine has actually been tested. Clearly this would not be tolerable to Congress.
The CEV Service Module is now being redesigned to use LOX/alcohol, LOX/Kerosene, or possibly even those old hypergolic propellants from Apollo 1.0.
Shrinking Command Module
I strongly criticised the original CEV CM as far too large for any of its projected missions. Sure enough, it has now been reduced in diameter from 5.5m to 5.0m with a corresponding reduction in weight. This may be intended to allow for the extra weight of hypergolic fuels in the SM, or perhaps just to allow a reasonable margin for weight growth in development.
Vanishing Crew Launch Vehicle
The huge upper stage of the CLV has also been reduced in diameter to match the downsized CEV, and the proposed air-start version of the SSME has been cancelled and replaced with the J-2S engine which has always had this capability. The reduced performance of the upper stage requires a 5-segment SRB for the first stage.
Of course, now that the CEV is only 5 meters in diameter, it can easily fit atop the existing Delta 4 or Atlas 5 boosters and the whole CLV development program is unneccessary. Look for this change during some future budget crisis.
No ISS Support Vehicle
The latest version of the RFP for the CEV program no longer includes the Cargo Delivery Vehicle. This was a version of the Block 1 CEV which was designed to deliver large indivisible modules of unpressurized cargo to the International Space Station. This would include such vital components as the Control Moment Gyros which are essential to maintaining the station's attitude.
Without the CDV, there is no way to deliver new CMGs after the Shuttle retires in 2010. Clearly, it is not expected that the ISS will still need them in the 2010-2016 period. This implies that the ISS won't be there at that time - or at least that NASA will not be supporting it.
The Shuttle Budget Crisis
Everyone (including Griffin) realizes that NASA's committments vastly exceed its current and future budget. Something has to be killed. The only things big enough to free up the money needed for the Moon program are 1) Shuttle and 2) Station.
Previous budget plans dodged this issue by assuming a major ramp-down in Shuttle funding between now and 2010 to pay for CEV and CLV development. This profile was absurd since the program assumes a full flight rate right up to the last mission. No major economies could be made without reducing that flight rate.
In recent months Griffin has redone the Shuttle budget plan using sensible assumptions and has been shocked... shocked to learn that there is a funding shortfall of $3-5B over the next four years.
This has "forced" Griffin to propose radical budget cuts in the 2007 NASA budget. Everyone's pet ox has been gored: aeronautics research, space science, the Search for Life, even Mars missions have all been cut after many months of fervent promises by Griffin that this would never happen.
This budget crisis is Stage 1 of Griffin's plan for Shuttle termination. By slashing dozens of popular space science and aeronautics programs, Griffin is brillantly undercutting the Shuttle's small remaining political support base. In the past week we have seen an outpouring of anti-Shuttle sentiment - and not just from the usual suspects, but from quarters that are usually pro-Shuttle or at least neutral. No one can understand why successful programs are being sacrificed to maintain an obsolete system that is headed for extinction in a few years anyway.
That Ever-Falling Foam
Stage 2 began with a little-noticed interview with the Orlando Sentinel. Griffin stated that tests have finally revealed the true cause of the dangerous foam shedding from Shuttle fuel tanks. It now appears that the expansion of the tanks when they are drained and warmed causes the frozen foam to crack. These cracks allow air to reach the metal tank during the next filling and liquify. The liquid air rapidly boils due to aerodynamic heating during launch and blows off large chunks of foam.
The logical result of this discovery would be to ground the shuttles again until a fix is found for this failure mode. But Griffin has not done this. The program is still proceeding toward a launch of STS-121 sometime in May, and the only fix being applied to the ET is to remove the PAL ramps that produced one of the biggest foam chunks on the last mission.
This measure addresses only part of the foam problem. Most of the foam has fallen from other areas of the tank (e.g. the piece which destroyed Columbia). It is virtually certain that foam will fall from STS-121 despite the ramp removal fix.
So in May we will again see video clips from Shuttle foamcams on our TV screens, with chunks of flying foam circled in red. Griffin will appear at a press conference with a suitably grave face and announce:
"I am shocked... shocked to learn that 3.5 years of work and many billions of dollars have failed to solve this grave safety defect. Clearly we cannot afford to spend more years and more billions wrestling with this flawed system. The 2010 deadline for Shuttle retirement is fast approaching, and the European and Japanese ISS research modules are nearing the end of their shelf lives. I am forced to ground the Shuttles for good -- and if the President doesn't like that decision he can fire me tomorrow and try to find someone else to run NASA."
Without the Shuttle, it is clear that NASA cannot complete assembly of the ISS or even boost the current configuration back to a safe altitude before the next solar maximum begins to drag it down. Griffin will order studies of alternate methods of finishing and supporting the ISS.
So in a year or so Griffin will be shocked... shocked to learn from these study groups that there no substitute for Shuttle that can be brought on line in time to save ISS. He will be "forced" to withdraw from the project and make a gift of the half-completed station to the international partners (meaning Russia). He may even offer to pay for the unlaunched European and Japanese science modules out of the huge stash of cash he will have on hand by then.
NASA critics like myself are often asked what they would do different if they were in charge. For the first time in many years I can honestly say: I would do nothing different from what the current Administrator is doing.
Jeffrey F. Bell is a former space scientist and recovering pro-space activist. Capitane Renault in Casablanca is his favorite movie character.
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