A massive explosion occurred right after the Antares rocket hit the ground. (Credit: NASA TV)
Sometimes things can go so well for so long that we forget – or try not to remember – just how difficult some tasks can be to achieve. Like getting to space, for example.
That reality was driven home during three days in October when an expendable booster exploded in Virginia and an experimental space plane crashed in the Mojave Desert in California. This is the first of a two-part series looking at these accidents.
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On Oct. 28, an Orbital Sciences Corporation Antares rocket exploded in spectacular fashion after takeoff from Wallops Island, Va. The rocket was carrying a Cygnus freighter bound for the International Space Station (ISS) under a contract with NASA.
“Launch is a really tough business,” said NASA Associate Administrator William Gerstenmaier at a post-crash press conference. “When we look at all these events that occur flawlessly and go well, we need to recognize how difficult and demanding this business really is.”
As spectacular as the Antares explosion was, its actual impact on NASA was fairly minimal. Orbital Sciences, on the other hand, found itself scrambling meet its commitment to the space agency while speeding up an existing plan to upgrade the Antares booster.
NASA’s relatively muted reaction to the accident was based on several factors. The accident occurred at a time when ISS was well stocked with supplies. There were nothing critical on the doomed Cygnus. Officials said the facility could have operated into March without any resupply ships visiting it.
Second, there is redundancy in the supply chain. The day after the Antares accident, the Russians launched another Progress freighter that docked with the station without incident. The Japanese space agency, JAXA, also periodically launches its HTV cargo ship to ISS.
Third, NASA has redundancy in its own supply chain. The space agency also contracts with SpaceX to deliver supplies using the company’s Falcon 9 booster and Dragon spacecraft. The company has flown five Dragons to the station without a failure; a sixth flight is scheduled for early January.
Finally, NASA officials were probably half expecting a failure like the one Orbital experienced. The space agency had partnered with Orbital and SpaceX to develop the Falcon 9, Antares and their respective cargo ships, and then awarded the companies delivery contracts. Given all the new hardware, the odds were that something would go wrong at some point. And it did.
Nobody died in the crash; just cargo was destroyed. All that could be replaced. With redundant delivery systems, everything would work out fine as long as there wasn’t a slew of accidents that destroyed multiple cargo ships.
Investigators have traced the cause of the explosion to a turbo pump on one of Antares two AJ-26 first-stage engines. The AJ-26 is actually the NK-33, which the Soviet Union built more than 40 years ago for its manned lunar program. A batch of the old engines had been imported into the United States years ago by Aerojet, which refurbished them for use on Antares.
Orbital never intended these engines – which are no longer in production – to be a permanent solution. At the time of the accident, the company was in the advances stages of securing a newer engine, the Russian-built RD-181, to power the first stage. The company had intended to continue using the AJ-26 in the meantime until the new engine could be secured, tested and integrated into Antares.
The accident changed that plan. The Antares crash, coupled with the earlier failures of two engines on the test stand, convinced Orbital officials that they no longer had a reliable stockpile of AJ-26 motors. Antares would stop flying while the engine replacement effort was sped up.
In the meantime, Orbital still has cargo to deliver for NASA. The company has contracted with rival ULA to launch a Cygnus aboard an Atlas V rocket late next year while it prepares Antares v.2 for flight. If that latter process takes longer than planned, Orbital will book another Atlas V for cargo delivery.
Proving it can recover from this accident and deliver cargo as contracted is crucial for Orbital. The company has no redundancy for its Antares and Cygnus programs. NASA is the only customer thus far, and solely for ISS cargo delivery. Orbital also is facing competition for NASA’s follow-on ISS supply contract from SpaceX, Boeing and Sierra Nevada Corporation.
Orbital is also the most failure prone of America’s rocket companies. ULA has never suffered a catastrophic failure with the Atlas V and Delta IV. SpaceX has reeled off 15 successful launches since losing its first three Falcon 1 rockets in test flights. Orbital’s launch record is much more troubled, however.
The Antares crash was the third time in the past five years that Orbital failed to deliver on NASA contracted mission. In February 2009, an Orbital Taurus XL rocket launched the space agency’s $270 million Orbiting Carbon Observatory into the Pacific Ocean after the vehicle’s payload shroud failed to separate. Two years later, NASA’s $424 million Glory satellite met the same fate, again due to the failure of Taurus XL’s shroud to separate.
So, Orbital is behind the eight ball, and it has a lot of work to do. NASA, on the other hand, is in relatively good shape, and it has multiple options going forward that won’t necessarily include Orbital.
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