Saturday, April 23, 2011

There Are Five Vehicles Competing To Succeed The Space Shuttle

By Frank Morring, Jr.

Washington U.S. spacecraft engineers with federal funding will pursue at least five different ways to replace the space shuttle in the next few years, from capsules that harken back to the 1960s to a spaceplane and a vertical-takeoff-and-landing craft that flies to orbit on a reusable booster.

Breakup of the year-long political logjam over funding for NASA this month cleared the way for the agency to announce the next phase of its Commercial Crew Development effort (CCDev-2) and gave Lockheed Martin a clear path to shift its old Orion crew exploration vehicle prime contract over to the new Multi-Purpose Crew Vehicle effort ordained in the three-year NASA authorization bill President Barack Obama signed last year.

“We’re committed to safely transporting U.S. astronauts on American-made spacecraft and ending the outsourcing of this work to foreign governments,” states NASA Administrator Charles Bolden. “These agreements are significant milestones in NASA’s plans to take advantage of American ingenuity to get to low Earth orbit, so we can concentrate our resources on deep space exploration.”

Bolden’s statement refers to the CCDev-2 awards, which went to Blue Origin, Boeing, Sierra Nevada Corp. and Space Exploration Technologies Inc. (SpaceX).

Lockheed Martin began work on Orion in 2006, when it beat out a Northrop Grumman/Boeing team for the prime contract (AW&ST Sept. 4, 2006, p. 22).

Procurement documents released with the CCDev-2 announcement give a first look at the work that has been underway at Blue Origin, a secretive start-up company based in Kent, Wash., that operates a remote test site in West Texas. The company plans to develop a reusable launch vehicle to carry its biconic seven-seat capsule to low Earth orbit, following an interim stage when it will offer suborbital tourist and scientific flights in a three-seat version.

Blue Origin received $22.005 million in CCDev-2 funding, exactly the amount it requested to hasten its development work, according to the procurement documents. Although it was the smallest award of the four granted, the agency apparently made it in the hope that the deep pockets of Blue Origin founder Jeff Bezos, who also founded, may open up an alternative to the approaches under development by Boeing, Sierra Nevada and SpaceX.

In its CCDev-2 proposal, Blue Origin says it will mature its seven-seat “Space Vehicle” through system requirements review, ground- and flight-test the pusher escape system it started under CCDev-1, and begin testing the 100,000-lb.-thrust liquid oxygen/liquid hydrogen engine for its “Reusable Booster System” (RBS).

“Each one-time use of current expendable booster technology represents a prime opportunity for cost reduction,” the company states. “Blue Origin’s RBS employs deep-throttling, restartable engines to perform vertical-takeoff, vertical-landing [VTVL] maneuvers for booster recovery and reuse.”

The company plans to launch its Space Vehicle initially on a human-rated Atlas V and transition later to the reusable booster. The vehicle apparently will use VTVL technology tested on an unpiloted vehicle dubbed New Shepard, which traces its heritage to the Air Force and NASA DC-X and -XA testbeds flown in the 1990s. It will return to Earth on dry land “to minimize the costs of recovery and reuse.”

According to its proposal, Blue Origin is conducting integrated testing of a “suborbital booster” that will carry a three-seat “suborbital capsule”—now in final assembly—to the edge of space.

“The suborbital vehicle will be fully reusable and capable of flying three or more astronauts to an altitude of over 328,000 ft. (above 100 km) for science research and adventure,” the Blue Origin proposal states.

Blue Origin plans to use its CCDev-2 funds to accelerate its work toward a full-up end-to-end space transportation system, including advancing the design of the Space Vehicle by completing “key system trades,” designing the thermal protection system in partnership with NASA’s Ames Research Center, defining the capsule’s biconic shape, and conducting the reviews necessary to generate “a baseline definition architecture and system requirements.”

In addition to Ames, Blue Origin has partnered with NASA’s Stennis Space Center to test engine thrust chambers; United Launch Alliance to integrate the Space Vehicle on the Atlas V; Aerojet for solid rocket motors and test facilities; Lockheed Martin Missiles & Fire Control High Speed Wind Tunnel in Grand Prairie, Texas, for Space Vehicle testing; and the Air Force High Speed Test Track near Alamogordo, N.M., to test the pusher escape system.

More is known about the other three CCDev-2 winners. Boeing has a pressure test article for its CST-100 capsule, which was on display at the National Space Symposium in Colorado Springs in mid-April. Machined from two pieces of aluminum for strength, the article is a pathfinder for a second version that will be built of lighter-weight 7075 aluminum alloy under the CCDev-2 phase.

Boeing received $92.3 million in CCDev-2 funding, the largest among the four recipients. Other tasks that will be carried out with the funding include evaluation of a lighter-weight engine for its pusher-type launch abort system, evaluation of the parachute and airbag-inflation systems for water landings, and full-scale tests of the pyrotechnics that will separate the CST-100 capsule from the service module prior to reentry.

The service module uses batteries instead of solar arrays for power, so the Boeing vehicle’s nominal flight profile calls for docking at the International Space Station (ISS) on the day of launch. However, it will have enough battery life to accomplish a second-day docking, if necessary. After that, it is designed to remain at the station for as long as seven months in a lifeboat role, drawing power from the ISS grid.

The company is still in the process of selecting a launch vehicle for its test flights and early missions and is designing the CST-100 to be able to handle loads on several candidate launchers.

“We’ve got four test flights scheduled,” says John Elbon, Boeing’s commercial crew development program manager at Boeing. “There’s a pad abort test in ’13, and in ’14 we have three tests that require launch vehicles: an uncrewed orbital flight test, so we’d fly in an automated way and spend a couple of days in orbit testing out the systems; an ascent abort test which would exercise the abort system at maximum dynamic pressure—Max-Q—and then finally a crewed flight test where we put a couple of test pilots in there and launch it, and then we’d be ready for operations.”

Sierra Nevada, like Boeing, was one of the big winners in the $50 million CCDev-1 competition, drawing $20 million to begin work on its Dream Chaser spaceplane, which would be launched on an Atlas V. It is essentially a composite version of NASA’s HL-20 lifting body that in turn was derived from the Russian BOR-4 test vehicle which flew in orbit four times, according to the Sierra Nevada CCDev-2 proposal.

Power is provided by the same hybrid propulsion technology used on the Scaled Composites SpaceShipOne and SpaceShipTwo suborbital spaceplanes, with a runway landing under the control of a pilot or autopilot. The company plans to use its $80 million in CCDev-2 funding to reach preliminary design review for the orbital vehicle and atmospheric drop tests of the engineering test article that has undergone structural testing.

Last year, SpaceX tested its Dragon capsule to orbit and recovery at sea in the cargo configuration it developed under NASA’s Commercial Orbital Transportation System (COTS) effort (AW&ST Dec. 13, 2010, p. 22). With its $75 million CCDev-2 award, the company plans to speed development of its side-mounted pusher-type launch abort system, including static testing, and prepare its initial design for crew accommodation in the Dragon for NASA astronauts to evaluate.

Phil McAlister, acting director of commercial spaceflight development at NASA headquarters and the selecting authority for CCDev-2, says the goal of the CCDev effort is to seed a commercial industry that can fly crews to the ISS by “approximately the mid part of this decade.” The second round is designed to mature designs that have a chance of growing into a full-scale system, which will be addressed in a third round of awards to be covered under an $850 million request for fiscal 2012.

For now, he says, the idea is to use the federal funds—plus the 10-20% the companies are required to post toward the development—to support “significant progress on maturing the design and development of elements of the system” or systems that ultimately will fly, with a conscious effort to back different approaches in a competitive approach.

“I would say at this stage of the game, competition is a very important part of our strategy,” says McAlister. “It incentivizes performance. It incentivizes cost effectiveness. We also believe that having skin in the game is also important.”

McAlister was executive director of the panel headed by former Lockheed Martin CEO Norman Augustine that found the old Constellation program of human exploration vehicles “unsustainable.” But one of those Constellation spacecraft, the Orion crew exploration vehicle, will continue in development as the Multi-Purpose Crew Vehicle (MPCV) Congress ordered as a backup to the commercial crew vehicles for space station trips, and as a NASA-owned deep-space vehicle for exploration crews.

To simplify and save money in the tricky transition, Lockheed Martin has cut out an entire test article for the MPCV effort, doubling up test objectives for the remaining articles to try to keep the vehicle within the tight schedule set by Congress.

By combining trials with particular test articles, the company plans to send an Orion capsule into orbit on its first test flight in 2013, says Cleon Lacefield, the company’s program manager. The first capsule produced is now being prepared for ground tests at company facilities near Denver, and once those are over that test capsule will be reinstrumented to fly on the first ascent abort test in 2014. Using the same test article in two trials will enable the company to start work on the test capsule that will fly to space for the first time.

“With the funding changes, the program realignments . . . we’ve been able to preserve the core of this test program and . . . make it more than it would have been by combining a bunch of tests into single articles,” says Jim Kemp, director of assembly, test and launch operations for the new spacecraft.

During the debate over NASA’s future direction Lockheed Martin kept working on the Orion capsule using Constellation funding available under appropriations language that prohibited NASA from terminating the program. The initial test article was built at the Michoud Assembly Facility in New Orleans, where it underwent pressure testing before being sent here for a more rigorous workout.

New instrumentation is being installed to test how it will hold pressure with a lot of its internal systems installed, including an instrumented window to measure how the glass flexes under pressure. Acoustic testing will follow, using generic acoustic loads that should cover any of the potential launch vehicles NASA chooses for the vehicle’s flight-test program. Kemp points out that the Orion was designed to launch on the Ares I rocket, which was under development by Constellation before the program was terminated.

That launch vehicle used a five-segment space shuttle solid-fuel booster rocket as its first stage, which would have generated acoustic loading beyond that produced by the liquid-fueled candidates for a test-flight launch vehicle.

If all goes according to schedule, piloted operations of the Orion could begin as early as 2016, Lockheed Martin says.

“[Last year,] we redefined the program to focus on a couple of things,” Lacefield says. “One of them is the first vehicle development for the flight test. It’s an orbital flight test where we really try to wring out 11 of the top 13 risk items on the vehicle. One of those we look at is the thermal protection system, so we’re doing high-velocity reentry to prove out its capabilities early in the vehicle development cycle.”

Testing of some MPCV systems could begin as early as May 1, when the space shuttle Endeavour is tentatively scheduled to dock with the ISS for the last time before its retirement. Nestled in next to the orbiter’s docking system will be the Sensor Test for Orion Relative Navigation Risk Mitigation payload, which will gather data on how the Orion navigation sensors will perform in an approach to the station.

Photo Credit: Blue Origin Concept

No comments:

Post a Comment