Orbital

Orbital ATK has conducted a ‘hot fire’ test of the improved first stage propulsion system of the company’s Antares medium-class rocket using new RD-181 main engines.

Conducted at Mid-Atlantic Regional Spaceport (MARS) site of Virginia Space, US, the test lasted for 30 seconds.

Following the test, the Antares engineering team will review the data over the next several days to confirm the successful completion of the test.

Once confirmed, the test will enable Orbital ATK to resume its cargo logistics missions to the International Space Station (ISS) from Wallops Island, Virginia, US, scheduled for next month.

However, a number of operational objectives were met during the test such as full propellant loading sequence, launch countdown and engine ignition and shutdown commands, as well as multiple throttle settings such as full engine power.

The test also confirmed the launchpad’s operation that covers propellant tanking and use of the water deluge system to protect the pad from damage and for noise control.

Before being transported to Orbital ATK, each of the new RD-181 engines had undergone hot fire acceptance testing at the facility of NPO Energomash, the manufacturer of the engine.

Last year, the engine had also completed a series of certification test.

Orbital ATK noted that the primary goal of the test was to validate the functionality of Antares’s integrated first stage, including new engines, modified stage 1 core, avionics, thrust vector control and pad fuelling systems in an operational environment.

The company will now return the first stage used in this test to the Horizontal Integration Facility for full reconditioning before using it on the OA-7 mission planned for later this year.

"This gives us further confidence in the first stage propulsion and in moving forward to launch."

In addition, the Antares rocket will be prepared for the upcoming OA-5 mission, which is in the final stages of integration, systems testing and check-out in preparation for launch this summer.

Orbital ATK Antares programme general manager and vice-president Mike Pinkston said: "The successful stage test, along with the extensive testing of each new RD-181, gives us further confidence in the first stage propulsion and in moving forward to launch.

"We are now focused on the OA-5 mission and launching the enhanced Cygnus spacecraft to the International Space Station on our upgraded, higher-performing Antares rocket."

So far, the company has completed five cargo delivery missions to the ISS and has delivered altogether 10,900kg of essential equipment and supplies to the ISS.

As part of a CRS contract with Nasa, Orbital ATK will deliver around 28,000kg of cargo to the ISS over 11 missions through 2018.

Orbital ATK has also been contracted for six initial missions for the follow-on CRS-2 programme.

Image: Conducted at Mid-Atlantic Regional Spaceport (MARS) site of Virginia Space, US, the duration of the test was 30 seconds. Photo: courtesy of Orbital ATK.