The
Northrop Grumman and Boeing team competing to build NASA's new Crew Exploration
Vehicle (CEV) unveiled a design Oct. 12 that echoes
the Apollo-like approach the agency adopted for its planned return to the Moon.
While the
team's CEV closely resembles the Apollo vehicle,
Northrop and Boeing officials said they have made numerous modifications to
increase mission flexibility and safety as NASA gears up to replace the aging
space shuttle.
The
Northrop/Boeing team is competing against Lockheed Martin to design and build
NASA's next-generation space vehicle, which is expected to transport astronauts
to the international space station, the Moon and eventually Mars. Northrop
Grumman officials estimate the winning team will need to construct three to
five CEVs in a year with different functionalities
depending on how frequently NASA wants to fly.
The agency
is expected to select a prime contractor by April 2006.
"To be safe
and soon we have to go with proven methods," Doug Young, vice president of
space systems at Northrop Grumman, said at an Oct. 12 news conference here,
noting the capsule design to be one of the most reliable and safest for launch
and re-entry.
The
Northrop/Boeing team proposes using lightweight materials for the command
module to deliver twice the available interior volume Apollo astronauts had for
their trips to the Moon. The new material will allow the 5.5-meter blunt body
capsule to ferry as many as six passengers to the international space station
and take up to four astronauts to the Moon.
"The size
and capacity of today's hardware will make this vehicle much different than
your father's Apollo," said Leonard Nicholson, the CEV
team's deputy program manager. While there is more room for passengers and some
cargo, Nicholson said the capsule will only weigh about 10 to 15 percent more
than Apollo because of the use of lightweight materials.
"It's a
very large capsule, when you think about it, with a lot of capability," Young
said.
As outlined
in NASA's architecture plan, the Northrop/Boeing CEV
is designed to launch into space atop a solid rocket booster like the ones
currently used to power the early phases of shuttle flights.
The design
includes a launch-abort system, a cylindrical structure that covers the top of
the command module like an inverted funnel during liftoff. If all goes
smoothly, the system will detach from the CEV one
minute into launch and burn up in the atmosphere. But in the case of an
emergency, the system is equipped with a rocket engine that will ignite and
pull the capsule away from the vehicle, either releasing the capsule to
parachute back to Earth or taking it on to orbit if close enough to space. From
there, the capsule can plan normal re-entry operations.
Once in
orbit for a Moon mission, the CEV would dock with the
lunar lander and the Earth departure stage --- both
of which are planned to be launched prior to the CEV
on a separate rocket --- then proceed to the Moon.
Their CEV module would have deployable solar arrays to gather
power while traveling in space and would carry more fuel than Apollo, allowing
astronauts to change orbit and land anywhere on the lunar surface rather than
being restricted by the positions of the Earth and the Moon as NASA was during
the Apollo missions. "Now we can go to the polar areas of the Moon" when we
couldn't before, Nicholson said.
While the
crew is on the surface, the CEV will be able to
operate autonomously in lunar orbit while crew members on the surface remotely
monitor its status. The CEV could orbit the Moon for
up to 180 days, Young said.
Once the
capsule returns to Earth, it is designed to touch down on land instead of in
the water like Apollo, but this process is still in the working stages,
Nicholson said. Currently the team is working on developing parachutes to
decelerate the vehicle, a small rocket to slow it down before impact,
deployable airbags, and a crushable structure that can be installed on the
bottom of the module to absorb the energy from landing.
The CEV also will have two-fault tolerant subsystems, Nicholson
said, which means the vehicle's critical components essentially will have two
back-ups. "On Apollo, there was only one-fault tolerance, so we had to start
talking abort right away" if a problem arose, he said.
While Young
would not discuss cost estimates for the design, government and industry
sources have said NASA's CEV is expected to cost $5.5
billion to develop and the Crew Launch Vehicle another $3.2 billion. Flight
testing is expected to add another $2 billion to $3 billion to the price tag.
NASA has
budgeted $1.8 billion for the CEV and Crew Launch Vehicle
design effort for 2006.
"Clearly,
it's all going to come down to cost and getting those numbers down to a bare
minimum that NASA is constricted by," Young said.