Updated Antares rocket launched to ISS two years after explosion
Image credit: Reuters
The Antares rocket, loaded with a capsule full of cargo for the International Space Station (ISS), has successfully been launched two years after a devastating launch pad explosion.
The 14-story rocket, developed by Orbital ATK, was propelled into space by new RD-181 engines made by Russian manufacturer NPO Energomash.
The engines, which Orbital ATK said would provide increased performance and flexibility, have replaced the original AJ26 engines. The AJ26 engine, a refurbished Russian NK-33 engine, was blamed for the massive blast on 28 October 2014, which destroyed not only the rocket, but also the Cygnus capsule with 2,300kg of supplies and scientific experiments for the space station aboard.
The AJ26 engines were based on a 1970s Russian design, re-purposed in the 1990s by US maker Aerojet. After the explosion, Orbital ATK ditched the engine and waited for two years for the brand new RD-181 to become available. In December 2015 and March 2016, the firm used the Atlas V rocket of the United Launch Alliance to launch the Cygnus capsule.
Orbital ATK signed a contract with NPO Energomash to deliver at least 20 kerosene-fuelled RD-181s.
The launch from Nasa’s Wallops Flight Facility in Virgina was delayed by five minutes to allow engineers to perform extra checks. The rocket finally took off towards the ISS at 7.45pm local time (11.40pm GMT)
“It’s such a feeling of elation to see the vehicle take off. ... I’m very happy to see Antares back,” said Amanda Davis, Orbital’s director of program engineering.
The Cygnus capsule positioned atop the rocket was packed with 2,400kg of food, supplies, equipment and scientific experiments bound for the space station. Nasa said it squeezed some extra food, clothing, laptops and spacesuit parts into the capsule as its second cargo vehicle, SpaceX’s Dragon, is currently grounded following last month’s explosion of the Falcon 9 rocket.
The cause of the explosion, which took place during fuelling for a pre-launch firing test, is still being investigated.
The Cygnus capsule is expected to reach the space station on Sunday. It will wait in space for a few days to allow Russian Soyuz with three new crew members to dock first on Friday.
Unlike Dragon, which is designed to survive the return to Earth, Cygnus will eventually be destroyed during atmospheric re-entry. However, it will first conduct a series of experiments. After departing from the space station, an experimental payload called Saffire II will trigger a combustion experiment designed to improve the understanding of how fire spreads in microgravity. Data from this experiment will be downloaded via telemetry.