The Super Heavy Fight
An Ed Kyle Commentary
May 19, 2010
The
Super Stand Off
NASA's Constellation Program has been cancelled, or has it?
NASA's 2011 budget as proposed by the White House deletes the program, but certain
members of Congress are fighting back. Congress is holding hearings featuring famous
astronauts such as Neil Armstrong and Eugene Cernan decrying the President's plan.
The fight is about the impending loss of Shuttle and Apollo era national assets,
which is another way of saying "jobs".
Meanwhile, certain teams inside NASA are working on plans to
continue Constellation in modified form. On May 17 the New York Times reported that
a MSFC team headed by Jeff Hanley, Constellation Program Manager, was working on an
accelerated plan to fly several more Ares I tests through 2014 followed by early testing
of a super-heavy lifter beginning the following year. In this plan, Ares I might not
be fully developed, but might instead be used to test systems for the bigger rocket.
The super-heavy, smaller than the previously-planned Ares V
rocket but still weighing more than 2,700 tonnes at liftoff, would borrow Ares I first and
second stages. Two five-segment boosters from Ares I would straddle a core
vehicle, which could be either 8.4 or 10 meters in diameter and powered either by a
cluster of SSME or RS-68 engines. For deep space missions, the rocket would be
topped by a J-2X powered Ares I Upper Stage. The rocket looks much like the
"Ares IV" studied by NASA several years ago.
Previous studies have shown that such a rocket, if powered by
four SSMEs, could lift more than 100 tonnes to LEO as a 1.5 stage rocket or, by topping it
with an Ares I Upper Stage to make a 2.5 stage machine, up to 45 tonnes to escape
velocity. This Super would be designed from the outset to serve both as a cargo and,
when topped by an Orion spacecraft and a Launch Abort System, a crew launcher. A
single launch could send an Orion on a trans-lunar mission, or into deep space on a
"Flexible Path" mission. Two launches might support a lunar landing.
A two-stage "core only" variant with no solid boosters,
and with propellant offloaded from the first core stage, could, if needed, serve as a LEO
crew launch vehicle.
The plan, a sped-up, lower-cost version of Constellation, seemed
designed to serve as a template for a NASA budget compromise between Congress and the
White House.
While some of his staff worked on Constellation plans, NASA
Administrator Bolden remained steadfast in his support of President Obama's proposed
Post-Constellation budget. The President's plan would cancel Ares I/Orion and Ares
V, extend ISS operations, develop commercial crew launch for ISS, and initiate propulsion
research that might be used by super-heavy lift rockets after 2020.
Bolden mentioned plans for kerosene/LOX propulsion during his
address to the same Congressional committee visited by Armstrong and Cernan.
Clearly, Bolden and Obama's plan replaces Shuttle-derived solid motors with liquid
hydrocarbons, something like Atlas Phase 2, the "Fat Atlas" described in the
2005 ESAS report.
Presumably, NASA would support development of an RD-180 class
U.S. engine for Phase 2. The Phase 2 core would be 5 or 5.4 meters in diameter and
would be powered by two RD-180 type engines. Three such cores would be clustered and
topped by a new "Fat Centaur" - something like the Advanced Common Evolved Stage
(ACES) proposed by ULA to lift up to 70 tonnes to LEO and 30 tonnes to escape. Such
a rocket would weigh more than 1,700 tonnes. A single-core first stage topped by an
ACES could serve as a 640 tonne crew launcher able to lift about 28 tonnes to LEO.
Atlas Phase 2 could fly from the existing ULA Atlas V launch site at Cape Canaveral
These two paths to Super Heavy stand in stark contrast. One
would preserve Shuttle External Tank infrastructure at Michoud, ATK's SRB production in
Utah, SSME or RS-68 and J-2X engine production and testing at Stennis, and Kennedy Space
Center's sprawling Launch Complex 39 - including use of the VAB and the under-construction
Ares mobile launcher. The other would see all of the above scrapped irrevocably in
favor of supporting EELV infrastructure. One approach appears to provide a more
capable launch vehicle. The other may offer a lower-cost rocket.
Launch vehicle choice is only part of the total struggle
currently underway, but decisions made in coming weeks and months could decide NASA's
future for decades.
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