The spectacular failed launch of an Orbital Sciences Antares rocket on 28 October has delayed the company’s proposed merger with ATK by about a month, but has not derailed the deal.

When announced in April, the two companies expected their all-stock merger might be completed by year-end. The pair are now looking to close on 27 January 2015, after holding separate shareholder meetings on 9 December, where both boards of directors will recommend approval of the tie-up.

The October launch attempt was the third of Orbital’s contract with NASA to provide International Space Station resupply missions. No-one was injured and the ISS crew were not left in any immediate danger of running low on provisions when the unmanned rocket and its Orbital-developed Cygnus cargo capsule were destroyed in a giant fireball just seconds after lift-off. However, the rocket and spacecraft – not including its cargo – were worth some $200 million, a cost to be shared between NASA and Orbital, which expects to complete its launch obligations under the space agency’s commercial resupply programme by the end of 2016. Repairs to the Wallops Island, Virginia launch facility should allow resumption of flights by the beginning of 2016.

However, Orbital is having to accelerate upgrades to the Antares rocket – which now look certain to include replacing its main engines.

According to Orbital, the probable cause of the explosion was a “turbopump-related failure” in one of the two AJ26 stage one motors. These are supplied by Aerojet Rocketdyne, which acquired from storage in Russia a number of Soviet-era NK-33 motors designed in the 1960s for the USSR’s ultimately-terminated Moon programme. Aerojet has refurbished and “Americanised” the engines, but one failed in testing earlier this year. Immediately after the Wallops incident Orbital described the AJ26 as “tough” and “robust”, but later said their use for Antares “will likely be discontinued”.

To meet its NASA-ISS obligations, Orbital will in 2015-2016 have to make “one or two” non-Antares launches of its Cygnus capsule. The exact short-term financial impact of the failure will depend on those launch arrangements, but it is not expected to be “material on an annual basis in 2015”, and there should be “no significant adverse effects” in 2016 or beyond.

ATK makes solid rocket motors, satellite systems and composite structures, while in addition to Antares and Cygnus, Orbital makes satellites and small launch systems – including missile interceptors and the Pegasus air-launched rocket. The merger proposal sees what will be known as Orbital ATK building on “complementary technologies, products and know-how, and highly compatible cultures”.

Before closing the deal, ATK will spin off its small calibre ammunition business, a main player in the US sporting market, as a separate company.

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Orbital's third Antares ISS flight, 28 October 2014

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