WASHINGTON — Orbital Sciences Corp. announced Nov. 5 it would accelerate the introduction of an upgraded version of its Antares launch vehicle after an Oct. 28 launch failure, and would use other launch vehicles for Cygnus missions to the international space station until the new Antares is ready.
Under the “go-forward” plan the company announced, Orbital will perform one or two launches of Cygnus cargo vehicles using a launch vehicle yet to be announced. Orbital Chief Executive David W. Thompson said in a conference call with financial analysts that the company is in discussions with three companies, two American and one European, to perform those launches.
“Indications at this point are favorable that these launch operators do have available capacity that is suitable for Cygnus launches as early as the second quarter of 2015,” Thompson said. That capacity, he said, extends through late 2016. A decision on the launch vehicle they will use will be made within a month, he said.
Thompson declined to identify the specific companies or vehicles Orbital is considering. Speculation, however, has focused on three companies:, Space Exploration Technologies Corp. and . None of the three companies would confirm that it is in discussions with Orbital Sciences regarding launching Cygnus spacecraft.
On the Nov. 5 call, Thompson did specifically rule out using the lower position of an Ariane 5 vehicle. While the Ariane 5 could accommodate the Cygnus, he said those launches go to different orbits not compatible with missions to the ISS. Industry sources said that it is unlikely Orbital would acquire a dedicated Ariane 5 launch given the vehicle’s expense and a full manifest of other missions.
Thompson said that Orbital also would accelerate the introduction of an upgraded version of Antares with a new first-stage propulsion system. Thompson declined to identify the engine the company has selected because “Antares continues to be in contention for a number of new launch contracts,” which would likely include the competition for the follow-on to the company’s current Commercial Resupply Services (CRS) cargo contract for the ISS. Proposals for that competition are due to NASA by Dec. 2.
“I would prefer to wait a bit before being specific about the approach that we’ve chosen for the new Antares main propulsion system,” Thompson said on the call when asked if the company had selected the RD-193 engine manufactured by Russian company NPO Energomash. That engine has been rumored to be a candidate for Antares, along with a solid-rocket motor from.
The new Antares would begin launches some time in 2016, Thompson said. With the increased capacity of the upgraded Antares, coupled with the capacity on the alternative launch vehicles Orbital is considering, he said Orbital believes it can transport the cargo planned for the remaining five flights under its CRS contract with NASA on four missions.
“The Cygnus capacity will expand, on average, to about 3,300 kilograms,” he said, compared with 2,600 to 2,700 kilograms of cargo planned for each of the remaining Cygnus missions using the original Antares.
Thompson said that Orbital will not ask NASA for additional funding for its CRS contract for using these alternative launch options and would offer only “modest, if any, short-term delays” for cargo delivery. He said Orbital has discussed its plans with NASA “at a conceptual level” but that details were still subject to change.
NASA spokeswoman Rachel Kraft said Nov. 7 the agency was still studying what modifications might be required to Orbital’s CRS contract if it does use different launch vehicles for its remaining missions.
Thompson said that Orbital’s costs for carrying out its plans “are not expected to be material” for 2015 as a whole. “The exact magnitude and timing of quarterly changes will depend on which of several specific variations on the overall plan we settle on,” he said.