Boeing expects to finish the design of its CST-100 capsule by early 2014, but officials say the commercial crew taxi may not be ready for orbital flights until 2016, assuming the company receives the anticipated funding from NASA in an award due by August.

Artist's concept of the CST-100 spacecraft approaching the International Space Station. Credit: Boeing
 
Last summer, Boeing's CST-100 schedule called for test flights of the reusable capsule in 2015.

According to John Mulholland, vice president and general manager of Boeing commercial programs, the schedule for CST-100 orbital flight tests and the craft's entry into service will depend on how much money Boeing receives in the CCiCap award and the subsequent certification phase.

Mulholland said in an April 6 interview the CST-100 program should reach its critical design review by early 2014. The review is a major milestone at the close of the project's design phase.

That is contingent upon NASA awarding funding to Boeing in the next round of the agency's commercial crew program. NASA plans to announce winners of the commercial crew integrated capability, or CCiCap, stage of the program in August, distributing between $300 million and $500 million in funding to at least two companies.

The CST-100 spacecraft, designed to ferry up to seven astronauts to and from low Earth orbit, is Boeing's proposal for NASA to acquire commercial crew transportation for the International Space Station.

Boeing, Sierra Nevada Corp., SpaceX and Blue Origin are currently receiving NASA funding under agreements set to expire this summer.

After the retirement of the space shuttle last year, NASA must purchase seats on Russian Soyuz spacecraft until a domestic vehicle is operational.

Congress cut NASA's fiscal 2012 commercial crew budget request by more than half, appropriating $406 million to the program for the fiscal year ending Sept. 30. The budget forced NASA to abandon its procurement strategy in the next phase of the program and return to Space Act Agreements, a more flexible, less rigid mechanism to partner with commercial providers.

The appropriation forced NASA to revise its forecast for the beginning of operational commercial crew missions from 2016 to 2017. The start of commercial crew service would come after a series of test flights by the spacecraft's private operators.

Even a $500 million award likely would delay Boeing's flight test program beyond 2015, according to Mulholland.

"With appropriate funding, we still can support a 2015 entry into service. I would say, and I can't be real specific on it, to hold the 2015 date, we would need, it appears, slightly more than the $300 million to $500 million in the base period," Mulholland said.

Artist's concept of the CST-100 spacecraft approaching the International Space Station. Credit: Boeing
 
The CCiCap Space Act Agreements will cover a 21-month base period, but NASA requested proposals lay out a series of optional milestones beyond the base period leading up to crewed test flights.

"We'll be running through qualification tests on all of the engines," Mulholland said. "We'll be doing more drop tests and landing tests. Pretty much every system on the vehicle will be going through some level of demonstration and qualification testing during that 21-month period."

After the 21-month base period ends in May 2014, Boeing's schedule calls for the completion of a structural test article and qualification testing.

"The other large-scale test will be a service module hotfire test," Mulholland said. "We'll have a complete service module with flight computer systems running. We'll have that test outside the 21-month period of performance, same with our qualification test vehicle. We'll be subjecting that to all the different environments we need to be certified for. And then we run into our three larger scale tests. The first one would be a pad abort test at the While Sands Missile Range. That will be done on the same stand that was used on the Orion pad abort test."

The CST-100 capsule, which measures nearly 15 feet in diameter, will initially launch into orbit on United Launch Alliance Atlas 5 rockets from Cape Canaveral, Fla.

Mulholland said Boeing plans to sign a firm contract for two Atlas 5 rockets soon after it hopes to receive a CCiCap award from NASA in August. The Atlas boosters will launch an uncrewed orbital flight test of the CST-100 capsule and a full-up demonstration mission with two Boeing astronauts on-board.

An ascent abort demonstration originally planned using a third Atlas 5 rocket has been removed from the Boeing test manifest, according to Mulholland.

After the test program is complete, NASA will certify the spacecraft to fly to the International Space Station with NASA astronauts.

While planning more ambitious tests in the future, Boeing engineers currently are navigating through a series of basic tests to verify the design of critical CST-100 systems such as parachutes, landing airbags, thrusters, propellant tanks and software.

Boeing completed a drop test of a boilerplate CST-100 capsule April 3.

John Elbon, vice president and program manager of Boeing's space exploration division, said engineers are analyzing data "relative to G loading" when the craft touched down in the Nevada desert.

"Overall, the drop test was very successful and we're very happy with the results," Elbon said.

Mulholland said another CST-100 drop in Nevada is scheduled for early May to test the capsule's drogue parachutes, which were not part of the April 3 test. Other milestones left in Boeing's current development agreement with NASA include a June hotfire of the CST-100's orbital maneuvering engine at White Sands Missile Range in New Mexico, a test of the capsule's landing airbags, and a software preliminary design review.

A cold flow test of the service module propulsion system is also on tap for June, along with a test of a service module propellant tank.

The CST-100's systems-level preliminary design review finished in early March.