Orbital Sciences to shift ISS resupply launches to other rockets

Today, Orbital Sciences announced both the results of its preliminary investigation of the explosion of its Antares rocket and its plans for moving forward with its launch contract with NASA. The launch vehicle, along with all the cargo destined for the International Space Station, went up in flames when a ground controller triggered a self-destruct sequence in response to indications that the rocket was not behaving as expected.

Early investigation results indicate that the problem can be traced back to problems with a turbopump that supplied one of the two main engines with fuel. These engines date back to the Soviet Union, and Orbital was planning on replacing them with something else in 2016. Now, it's accelerating its replacement (although it's not clear by how much) and it's unlikely that Antares will fly with the existing engines in the interim.

That still has the potential to leave a gap in NASA's resupply schedule but Orbital indicates it's got that covered, too. The Cygnus supply vehicle was designed from the start to ride to orbit on a variety of commercial launch vehicles, so Orbital will look to continue supplying the ISS by mating it to someone else's rocket.