Orbital Sciences Corporation aborted the first Antares medium-lift rocket test launch into space on 17 April from Wallops Island, Virginia. The test mission was scrubbed 12min prior to lift-off due to "premature separation" of one of the "umbilicals" on the second stage of the rocket.
According to NASA, the rocket will now have to be defueled and safed. It will take engineers at least 48h to figure out what went wrong before the next launch attempt.
Future versions of the Antares, which can carry 5,000kg (11,000 lb), are expected to resupply the International Space Station (ISS). Orbital Sciences is contracted to fly a total of 10 resupply missions to ISS.
Orbital Sciences developed the first stage of the rocket using Aerojet AJ-26 engines that are based on old Russian Kuznetsov NK-33 engines originally designed for the Soviet N-1 launch vehicle. It also uses Russian developed fuel tanks.