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Virgin Galactic released this photo last week of the second SpaceShipTwo currently under construction, which the company says could be ready for test flights next year. (credit: Virgin Galactic)

Moving beyond the accidents


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Last week, the initial shocks of the double whammy of commercial space transportation accidents—the October 28 failure of an Orbital Sciences Corporation Antares rocket and the October 31 crash of Virgin Galactic’s SpaceShipTwo—began to wear off. The investigations into the failure are still ongoing, but both companies are starting to take steps to move beyond responding to the accidents themselves and looking ahead to how they’ll get back on track.

But just as the two accidents are different, the responses the two companies are taking are also different. Orbital, with the need to fulfill a NASA contract, is now forced to look to other companies to help is deliver cargo to the International Space Station (ISS). Virgin Galactic, on the other hand, appears to be staying the course, albeit with unavoidable delays, with its suborbital vehicle as the investigation into the accident that killed one pilot and injured another goes on.

Orbital’s “go-forward” plan

The failure of the Antares rocket left Orbital in a predicament. They have a spacecraft—Cygnus—still capable of transporting cargo to the ISS. The spacecraft has performed well on its previous missions, bringing cargo to the station and disposing of the station’s garbage at the end of ach mission. But with the Antares out of service, potentially for an extended period, there was no away for Orbital to get Cygnus to the station on its own.

“Indications at this point are favorable that these launch operators do have available capacity that is suitable for Cygnus launches as early as the second quarter of 2015,” Thompson said, not disclosing who the operators are.

On November 5, the company announced what it called its “go-forward” plan for continuing deliveries of cargo to the station. Part of that effort involves accelerating development of a new version of Antares with a different first-stage engine, a project that was underway prior to the launch failure. That vehicle, with a new engine that the company has already selected but has not yet announced, could be ready for launches some time in 2016.

In the interim, Orbital will become a customer of commercial launch services. The company disclosed that it will seek to launch one or two Cygnus spacecraft on another company’s rocket, starting as soon as next spring. Orbital CEO David Thompson said the company has been in discussions with three companies, two in the US and one in Europe, to launch Cygnus missions.

“Indications at this point are favorable that these launch operators do have available capacity that is suitable for Cygnus launches as early as the second quarter of 2015,” Thompson said in a conference call with investors. That capacity, he said, extends through late 2016.

Thompson declined to disclose which companies Orbital has been in discussions with. However, the two American companies are most likely SpaceX, which would offer its Falcon 9 rocket; and United Launch Alliance, with its Atlas and Delta vehicles. The only qualifying European company would be Arianespace, which could launch Cygnus spacecraft on its Soyuz rocket from French Guiana. (Thompson ruled out hitching a ride on a larger Ariane 5, since its commercial missions go to orbits not compatible with the ISS.)

None of those three companies have confirmed that they are in discussions with Orbital for launching a Cygnus. Thompson said they expect to make a decision on the vehicle they’ll use for the Cygnus flights in the next month or so.

The combination of the non-Orbital Cygnus launches, which will have increased capacity over the original Cygnus, and the upgraded Antares that Orbital plans to roll out in 2016, mean that each Cygnus will be able to carry more cargo: about 3,300 kilograms, on average, versus the 2,600 to 2,700 kilograms planned for the remaining Cygnus missions using the original Antares. That, Thompson said, will allow Orbital to meet its cargo requirements under its NASA contract in four missions, instead of five.

Asked during the conference call if the decision to discontinue the AJ26 engine was linked to a “fundamental reliability issue” with the engine, Thompson responded, “I would say that’s a good assessment.”

That approach, though, will come at some additional cost for Orbital, primarily in the form of buying the non-Orbital launches from Arianespace, SpaceX, or ULA. Orbital had already factored in spending on the upgraded Antares in its plans, Thompson said, adding that the overall additional costs would not be “material” to the company in 2015.

Thompson all but ruled out using the original Antares, with its AJ26 engines—refurbished versions of Soviet-era NK-33 engines—in the future. He said the investigation into the failure suggested that a turbopump in one of the rocket’s two AJ26 engines malfunctioned 15 seconds after ignition, causing the failure.

“We will likely discontinue the use of the AJ26 rocket engines,” Thompson said, “unless and until those engines can be conclusively shown to be flight-worthy.” Asked during the conference call if the decision to discontinue the engine was linked to a “fundamental reliability issue” with the engine, Thompson responded, “I would say that’s a good assessment.”

SpaceShipTwo’s next steps

While Orbital announced plans to move ahead with Cygnus cargo deliveries last week as the Antares investigation sheds light into its engine failure, less information has been coming out of the investigation into the fatal October 31 crash of SpaceShipTwo north of Mojave, California. Yet, Virgin Galactic has been showing increased confidence about the future of the vehicle.

The National Transportation Safety Board (NTSB) held their last on-site press conference in Mojave late November 3, adding few details about the investigation, which is now focused on why co-pilot Mike Alsbury unlocked SpaceShipTwo’s feathering mechanism several seconds earlier than planned. While not moving to raise the vehicle’s two tail booms, they did raise nonetheless, and seconds later the vehicle broke apart.

NTSB acting chairman Christopher Hart, in that final briefing in Mojave, said the NTSB was forming a “human performance” team to study the accident alongside the other technical teams. It would look at issues associated with vehicle displays, checklists, and other issues that might have played a factor, although the NTSB had yet to blame the accident specifically on the premature unlocking of the feathering mechanism.

“All of their deposits are fully refundable, but so far we have had very few customers request refunds,” Branson claimed. “On the contrary, we have had inquiries about purchasing Virgin Galactic tickets this week.”

Virgin Galactic, though, has gone farther than the NTSB in its assessment of the investigation. “The NTSB indicated that the lock/unlock lever was pulled prematurely based on recorded speed at the time, and they have suggested that subsequent aerodynamic forces then deployed the feathering mechanism, which resulted in the in-flight separation of the wings and vehicle,” it said in a statement issued November 4.

The full investigation, including analysis by NTSB into the causes of the accident and what can be done to prevent it in the future, may take up to 12 months to complete, Hart said, a timeline not uncommon for such investigations. However, he suggested it could be done more quickly given the wealth of information, including telemetry and video from SpaceShipTwo, not usually available in a crash investigation.

One issue that will be raised is why the feathering mechanism is unlocked at all during the powered phase of flight. Normal procedures, according to the company and NTSB, call for the feather to be unlocked once the vehicle reaches Mach 1.4; it was traveling at Mach 1.0 when the feather unlocked on its October 31 flight. Some note that the unlocking of the feather during the powered phase of flight is itself a safety measure: should the feather not unlock, the engine could be shut off, allowing SpaceShipTwo to glide to a landing normally without reaching speeds and altitudes high enough whether the feather would be required for reentry.

Even as the NTSB investigation continues, Virgin is looking to continue development of the second SpaceShipTwo vehicle, which was about 65 percent complete at the time of the accident. At a media tour last month, prior to the accident, company officials said the vehicle could be ready for test flights in 2015 and be delivered for commercial service in 2016.

“The second SpaceShipTwo is already two-thirds complete, and our team are pouring themselves into that project with heightened resolve. Our will is indefatigable, and our team is determined,” Virgin Galactic CEO George Whitesides said in a November 7 statement.

The accident has caused some customers of the company to think twice about flying. Various reports indicate than between 20 and 30 of the company’s more than 700 customers have asked for refunds.

In a statement posted on the main Virgin website November 6, Sir Richard Branson downplayed those reports. “All of their deposits are fully refundable, but so far we have had very few customers request refunds,” he said.

“On the contrary,” he added, “we have had inquiries about purchasing Virgin Galactic tickets this week, including many new Future Astronauts either signing up or in the process of signing up to show solidarity with the team and the project.”

For whom is this a bigger deal?

Immediately after the SpaceShipTwo accident, Virgin Galactic appeared to be in greater danger than Orbital Sciences was after the Antares failure. After all, Virgin’s only existing spaceplane was destroyed, and initial speculation focused on the vehicle’s hybrid rocket motor, any flaw in which could require an extensive, and expensive, redesign. Orbital, by contrast, is a larger and more diversified company—its annual revenues are more than $1 billion—and has weathered launch failures in the past.

Should Orbital lose the follow-on ISS cargo contract competition, and is unable to find other customers for Antares, it may be forced to decide whether it’s worth continuing to develop that vehicle, or give up trying to crack into the medium-class launch market.

However, the Antares failure may have bigger implications in the long run for Orbital than the SpaceShipTwo failure has for Virgin. In the latter case, it appears that no major redesign of the vehicle or its engine are needed, although likely some changes in components and procedures will be required to prevent premature deployment of the feathering system. Assuming that the NTSB investigation finds no other serious problems, and Virgin Galactic has the needed financial and other resources, a second SpaceShipTwo could be in commercial service in 2016.

For Orbital, the stakes, at least in its share of the launch business, may be higher. Forced to abandon the AJ26 engine sooner than planned, it must now accelerate development of the new Antares with the new engine (rumored to be either a variant of the Russian RD-180 or a solid motor from ATK.) The company has declined to name that new engine because Orbital is competing for launch contracts, including a follow-on for its ISS commercial cargo contract, proposals for which are due to NASA early next month.

What if, though, Orbital fails to win a new cargo contract? It will be likely competing against SpaceX, but also may be facing off with a cargo variant of Boeing’s CST-100 and Sierra Nevada Corporation’s Dream Chaser vehicle, which lost out—for now, pending a protest with the Government Accountability Office—on the commercial crew contracts. Despite Orbital’s position as an incumbent, it has no guarantee of winning.

Unlike SpaceX, which leveraged its development of a commercial cargo transportation system for NASA into contracts for commercial satellite launches on its Falcon 9, Orbital has yet to win any additional contracts for its Antares rocket beyond its NASA cargo awards. Should Orbital lose the follow-on ISS cargo contract competition, and is unable to find other customers for Antares, it may be forced to decide whether it’s worth continuing to develop that vehicle, or give up trying to crack into the medium-class launch market.

Both accidents are setback their companies, and, in the case of SpaceShipTwo, a tragedy for Alsbury’s family and friends. Which failure has a bigger effect on its company, and the larger commercial space industry, remains to be seen.


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