Orbital ATK [OA] delayed a hot-fire test of its re-engined Antares launch vehicle by two months to early May, according to a company spokeswoman.

Orbital ATK spokeswoman Jennifer Bowman said Wednesday the new RD-181 engines are currently installed in the first-stage article. She said the company originally set a March test date based on an earlier set of test requirements, but later revised those test requirements with its NASA customer, who coordinates and approves such test requirements.

Orbital's Cygnus capsule and Antares rocket Oct. 28, 2014, prior to failure at NASA's Wallops Island Flight Facility. Photo: NASA.
Orbital’s Cygnus capsule and Antares rocket Oct. 28, 2014, prior to failure at NASA’s Wallops Island Flight Facility. Photo: NASA.

Bowman said Orbital ATK is being “extremely meticulous” in its preparation for this test and for resuming flights from the Mid-Atlantic Regional Spaceport (MARS) at Wallops Island, Va., this summer. She said the company is still working with NASA to identify a launch date.

Bowman said late Wednesday the hot fire test will be of Orbital ATK’s integrated and upgraded Antares 230 booster. The original plan, she said, was to use the intended return-to-flight Antares vehicle and test for a duration of 20 seconds at a maximum of 67 percent power (thrust).

Bowman said Orbital ATK later agreed with NASA to revise the test plan to a duration of 30 seconds at maximum 100 percent power (thrust). Since the vehicle is “obviously” designed to lift off at full thrust, she said, the test plan and associated hardware had to be changed and instead of using the return-to-flight vehicle, an Antares 230 booster will be used with provisions to hold down the booster at full thrust.

Bowman said while this differs from Orbital ATK’s initial flight plan, this is nearly the same test configuration that was used for the company’s initial Antares 130 booster hot fire test. The change in test plan and associated hardware to be used, she said, dictated a change in schedule. The engines for both the hot fire test booster and the vehicle to be used in the Commercial Resupply Services-5 (CRS-5) mission have been integrated and check-outs of the engine and booster system have commenced for the hot fire test.

Orbital ATK is re-engining its Antares launch vehicle with Russian RD-181 engines. Company officials said in December that the company was “sure” it didn’t need a preliminary flight test of Antares with its new engine because the engine was “as close” to a drop-in replacement as the company could get (Defense Daily, January 8). Orbital ATK originally planned to move away from Antares’ AJ-26 engine, but the September 2014 launch failure at MARS accelerated those plans. The AJ-26, developed by Aerojet Rocketdyne [AJRD], is a refurbished NK-33 designed to launch the N1 Russian rocket on lunar missions.