Spaceflight Insider

Antares return to flight targeting late August

Orbital ATK Antares rocket NASA Wallops Flight Facility Pad 0A NASA Joel Kowsky photo posted on SpaceFlight Insider

An archive photo of Orbital ATK’s Enhanced Antares rocket. Photo Credit: Joel Kowsky / NASA

Dulles, Virginia-based Orbital ATK is targeting August 22, 2016, for the return to flight of the company’s Antares rocket. This redesigned “Enhanced” booster will launch the next Cygnus cargo ship, the S.S. Alan Poindexter, to resupply the International Space Station (ISS).

This mission, dubbed OA-5, will launch out of Wallops Flight Facility in Virginia from the Mid-Atlantic Regional Spaceport’s Pad-0A. It will not only test out the upgrades to Orbital ATK’s Antares booster but also loft the sixth Cygnus to the space station as part of the $1.9 billion dollar Commercial Resupply Services contract with NASA.

The Antares 230 will be the first launch since the ill-fated Orb-3 mission in October 2014. That flight lasted just 15 seconds before the turbopump in the AJ26 engine—a refurbished Russian-built NK-33 engine—exploded. The vehicle, only 300 feet (91 meters) off the pad, came crashing back down, causing an estimated $15 million in damages to the launch pad.

An investigation found possible reasons for the failure included ingestion of loose debris or a manufacturing defect. As such, the company has since done away with the AJ26 in favor of another Russian-built engine—the RD-181. A 29-second static fire test already occurred on an upgraded Antares in late May.

Each of the rocket’s two RD-181 engines will provide 432,000 pounds (1,920 kilonewtons) of thrust at liftoff. That, with other upgrades, should allow for the booster to deliver up to 15,000 pounds (7,000 kilograms) to low-Earth orbit.

The OA-5 Cygnus cargo ship, when it launches, should take about two days to arrive at the ISS. There the Expedition 48/49 crew will capture and berth the spacecraft with the robotic Canadarm2. After that, the crew will unload the supplies, experiments, and other equipment.

After spending a couple months berthed to the station, the OA-5 Cygnus will be detached and sent to a safe distance for some eight days in order to remotely conduct the Saffire-2 experiment. The Saffire-1 study was conducted aboard the last Cygnus in late May.

Unlike the first Saffire, which tested a single cotton-fiberglass card that was 12 by 36 inches (30 by 91 centimeters), this second experiment will use nine smaller pieces—each 2 by 12 inches (5 by 30 centimeters).

After the experiment is conducted, ground teams will command the spacecraft to de-orbit somewhere over the Pacific Ocean.


Derek Richardson is a student studying mass media with an emphasis in contemporary journalism at Washburn University in Topeka, Kansas. He is currently the managing editor of the student run newspaper, the Washburn Review. He also writes a blog, called Orbital Velocity, about the space station. His passion for space ignited when he watched space shuttle Discovery leap to space on Oct. 29, 1998. He saw his first in-person launch on July 8, 2011 when the space shuttle launched for the final time. Today, this fervor has accelerated toward orbit and shows no signs of slowing down. After dabbling in math and engineering courses in college, he soon realized that his true calling was communicating to others about space exploration and spreading that passion.

Reader Comments

Laurence Klein

Thank you for the article. The RD-181 thrust is claimed in a Wikipedia article to be 100,000 pounds greater than the AJ-26/NK-33 engine it replaces, which would make the thrust about 440,000 pounds. There will be two of these engines on the Antares.

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