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The Constellation Empire Strikes Back

Constellation, the Bush administration's plan to return to the moon, was canceled a couple years ago. But not all of Constellation was canceled. The Orion crew module, designed to go to lunar orbit and back, survives, with plans to test fly on a Delta IV rocket in a couple years, and Congress, eager to preserve the Space Shuttle jobs base, demanded that NASA reinstitute a new heavy-lift launch vehicle to replace the canceled Ares V with the Space Launch System. So at this point, despite the cancellation, Constellation continues to waste money, except for the Ares I, the new crew rocket that NASA was developing. Derived from Space Shuttle and Apollo hardware, it used a new five-segment version of a shuttle solid rocket booster (SRB) as a first stage, with a new LOX/hydrogen upper stage. At the time of cancellation, it had been experiencing development issues, missing performance, cost and schedule milestones.

Now it looks like even it could be resurrected.

Last February, ATK, the manufacturer of the SRBs, made a joint announcement with Astrium, the company that builds the European Ariane V rocket, that they were proposing a new rocket, renamed Liberty, similar to Ares 1, except that instead of developing a new upper stage, it would use the Ariane first-stage core as a second stage atop the SRB. The idea was that with two proven existing stages, the development cost would be low and the schedule rapid, with a first flight planned for 2015. There's sense of deja vu here -- the Ares 1 was advertised as "Safe, Simple, Soon." Here's the old web site, courtesy of the Wayback Machine. Many were skeptical at the time, both in terms of how much sense it made technically, and whether or not there was a business case for it. The team received no funding from NASA, but it signed a Space Act Agreement with the agency last fall to do studies on such a system for the commercial crew program with its own funds.

On Wednesday, the results of its study were announced at a space technology conference in Los Angeles. It was no longer just a proposed new rocket looking for payloads and funding, but a full new commercial venture with several team members to provide launch services for crew and cargo, including a new crew capsule, and new escape system that has already been partially tested by NASA and ATK at the Wallops launch range in Virginia.

How does it differ from Ares 1 (and its Orion capsule)?

As was announced last year, the first stage seems to be exactly the same -- it will be the five-segment SRB that was expanded from the original four-segment version that the Shuttle used in order to lift an upper stage that had grown from the original Ares 1 upper-stage concept when NASA switched from the higher performance but more costly Space Shuttle Main Engine (SSME) to a new, cheaper engine called the J2-X (it is derived from the venerable J-2 design used on the upper stage of the Saturn V for Apollo). This SRB is the same booster type that is planned to be used for the Space Launch System, scheduled to debut in its Block 1 (70 metric ton) version in 2017 (it will use two of them). But unlike the new second stage for Ares, the second stage of Liberty is an almost-off-the-shelf Ariane V core (the Ariane V launcher utilizes strap-on solid rocket motors to augment its lift-off thrust). Ariane V was designed from the beginning to carry humans, because one of its planned payloads was the proposed French Hermes space plane, which was later cancelled. It is a LOX/hydrogen stage using a single Vulcain engine of about 300,000 lbf of thrust, which gimbals for pitch and yaw control. Roll control is provided by cold-gas helium thrusters on the periphery of the stage, and presumably, as an upper stage, this system will provide that function for the entire vehicle until first-stage separation, as the SRB itself has no intrinsic roll control (the Shuttle controlled roll by gimballing the nozzles on the two SRBs attached to its external tank).

One issue that must be dealt with is the fact that as a first stage, the Vulcain engine starts before liftoff, whereas as an upper stage, it will have to be "air started" after separating from the SRB first stage. One of the reasons that the SSME was abandoned by NASA for the J2-X was because, as a very complex staged-combustion engine, it required ground-support equipment on the pad to bring it up to thrust, and there would have been difficulties with an air start. Snecma, the manufacturer of the simpler gas-generator Vulcain, believes that it can incorporate any systems needed into the vehicle to allow it to ignite post separation.

ATK claims that thrust oscillation, a major development issue for the Ares 1, is mitigated by the new configuration, because the Arian stage has different inertial characteristics, and won't resonantly "couple" with the five-segment solid vibrations the way the Ares 1 upper stage did (there were concerns for that vehicle that the shaking could make it difficult for the crew to see gauges or operate controls, and might even injure them and damage the upper stage and capsule). However, there remains at least one area of uncertainty. The five-segment version of the SRB has never flown. It has been statically fired on a horizontal test stand, but there is no direct data of what its vibration and dynamic characteristics will be in free flight. However, in response to my question about it, ATK claims that the combination of the static test firing and the test flight of the Ares 1-X vehicle a couple years ago, which flew a four-segment version with a "dummy" fifth segment for testing aerodynamics, allowed them to calibrate their models and give them confidence that their simulations will be valid in a five-segment vehicle.

But the biggest announcement yesterday was the new crew capsule and the abort system.

The capsule will be similar to Orion, except that it will utilize a composite structure, rather than metal, and it will have a less robust heat shield, because it is designed to come back only from low earth orbit, and not from deep space, which would require dissipation of twice the energy during entry.

For abort, Ares/Orion used a traditional launch tower on top of the capsule with solid rockets (called a "tractor" configuration) that would rapidly pull the capsule away from the vehicle in the event of a problem. The tower would be jettisoned once safely past any need for an abort to improve payload performance. The ATK capsule uses a boost protection shield on top of the capsule, with side-mounted solid motors for escape, which reduces total height of the stacked launch system (ceiling clearances in the Vehicle Assembly Building at Kennedy Space Center were an issue for the Ares 1 with its tower). It would also be jettisoned at a safe altitude.

The total vehicle would be stacked in the VAB and moved to the Shuttle launch pad 39-B using a mobile launch platform (the Saturn/Shuttle MLP is currently being modified for the Space Launch System, so it's not clear if they'll be able to use it, or have to build their own). Kent Rominger, the Vice President of Business Development for ATK (and former Chief of the NASA Astronaut Office), who led the press conference, said that they were looking for government satellite markets. But there was no discussion of what pads they might use at Vandenberg Air Force Base, the west-coast launch site needed to get to high-inclination orbits where many remote-sensing, weather and spy satellites reside.

The emphasis of the sales pitch for the program was clearly crew safety, with claims of only a 1 in 1200 chance of loss of crew, due to the supposed intrinsic reliability of both the SRB and Ariane, in combination with the abort system. This will be a key issue, because the team admits that they won't be able to beat SpaceX's stated price of $20M per seat for a Dragon ride, though Rominger did tell me that they'll beat the Russian's price of $62M. Beyond that, he was unwilling to stipulate a price, for what he said were competitive reasons. However, if it carries seven crew (as is planned for the other Commercial Crew competitors) that would put an upper limit of $400M per flight in their cost for them to make any profit at all. How much less than that they'll be able to charge for satellite launch will determine whether or not they are competitive against the Atlas, Delta and Falcon. It is also unclear what would happen to their costs were the Space Launch System to be canceled, and they would have to carry the full overhead of SRB manufacturing facilities on their own rather than splitting them with the other program.

Which brings us to the politics.

While Liberty now has a full-fledged business plan and proposal for a commercial system, one thing that hasn't changed since the initial announcement last year is that it's still looking for money. Rominger said that with proper funding, they could fly by 2015, but left to their own discretionary resources, it might not happen until the next decade. So much will depend on how much money Congress gives NASA for the commercial crew program, and how favorably the agency looks upon the new proposal, relative to the existing competitors of Boeing, SpaceX, Sierra Nevada and Blue Origin.

This past week, some congressional Republicans have been acting like socialists (as they seem prone to do when it comes to space), demanding that NASA not continue the competition, but instead narrow down to a single contractor next year, despite the fact that NASA says that this would double the program costs and delay it.

The question is, if NASA were to go to a single contractor now, who would it be, and does Congress have a preference? Awarding a new contract to ATK would be a completion of the restoration of the costly and unsustainable Constellation program. Unfortunately, the people in Congress who supported that program, and were angry when it was canceled, are less concerned with cost or progress than they are with the jobs provided in their districts and states, and they'd be very happy to see such a restoration happen. They would argue (with talking points provided by ATK) that Liberty has synergy with the Space Launch System, that it will be the safest solution, and that it promotes foreign cooperation. And unfortunately, I heard last week from a fairly highly placed government employee in a position to know that the timing of Wednesday's announcement was no coincidence. So stay tuned.