Engine trouble delays Northrop Grumman Cygnus XL delivery to International Space Station

CAPE CANAVERAL, Fla. — A newly launched Northrop Grumman resupply capsule experienced an engine problem less than two days after liftoff, forcing a delay to its planned docking with the International Space Station, NASA said Wednesday.

The Cygnus capsule, a newly built extra-large version called Cygnus XL, lifted off Sunday from Florida aboard a SpaceX rocket carrying more than 11,000 pounds (about 5,000 kilograms) of cargo intended for the station's seven residents. Flight controllers reported that the capsule’s main engine shut down prematurely while performing a burn to raise its orbit, and the planned Wednesday rendezvous is on hold while teams assess alternatives.

NASA said in a statement that mission managers are reviewing flight data and evaluating possible contingency plans to try to get the vehicle to the station. The agency did not provide a timeline for a revised docking attempt. Northrop Grumman, which operates the Cygnus cargo system under contract to NASA, also is working with flight control teams to determine the next steps.

The shipment includes food, scientific experiments and spare parts, including components for the station’s toilet and other systems. The Cygnus XL is the largest version of Northrop Grumman’s resupply vehicle to date and was making its debut on this mission, designed to carry a heavier payload compared with earlier Cygnus models.

The International Space Station orbits about 260 miles (420 kilometers) above Earth. Northrop Grumman is one of NASA’s two private cargo suppliers for the station, with SpaceX providing the other commercial resupply service. Russia also continues to deliver cargo to the orbital laboratory; a Russian shipment arrived over the weekend.

NASA and Northrop Grumman have postponed routine docking operations until engineers complete their assessment. Flight controllers will determine whether the spacecraft can resume its planned approach using alternate engine burns, combinations of smaller thrusters, or other corrective maneuvers. Officials did not indicate whether the cargo will be jeopardized or whether station operations would be affected.

The mission marks an important capability expansion for Northrop Grumman's commercial cargo services, and the company had been preparing the extra-large Cygnus to support more science experiments and larger logistics loads for the seven-person crew aboard the station. Engineers will analyze telemetry from the aborted burn to identify the cause of the premature shutdown and decide whether the vehicle can be recovered for docking on a delayed schedule.

Further updates are expected once NASA and Northrop Grumman complete their joint review of the spacecraft’s systems and potential recovery options.