A problem with the main engine on Northrop Grumman's Cygnus XL spacecraft will keep it from delivering 11,000 pounds of supplies and experiments to the International Space Station as scheduled on Wednesday.
In a statement released Tuesday afternoon, NASA said ground teams are evaluating backup plans that might still allow the Cygnus spacecraft to reach the space station, just not on schedule. The problem arose early Tuesday when the spacecraft's main engine shut down earlier than expected during two burns to boost the ship's orbit for its rendezvous with the ISS, according to NASA.
Officials didn't release any other details about the engine problem, but all other systems on the Cygnus XL spacecraft are performing as designed, NASA said. The agency said a new arrival date and time at the space station is "under review."
Seeking another way
The Cygnus XL spacecraft launched Sunday at 6:11 pm ET (22:11 UTC) aboard a SpaceX Falcon 9 rocket from Cape Canaveral Space Force Station, Florida. A series of main engine burns was supposed to bring the spacecraft from the orbit the Falcon 9 released it in to an orbit matching the altitude of the ISS.
The mission was on track to arrive at the station early Wednesday. Unlike SpaceX's Dragon crew and cargo ships, which fly themselves to automated dockings at the station, the Cygnus must be captured by the lab's Canadian-built robotic arm. NASA astronaut Jonny Kim was set to use the arm to capture the Cygnus spacecraft as it flew within 30 feet of the complex. The robotic arm would then place the spacecraft on an attachment port on the station's Unity module for a stay of up to six months.
This is Northrop Grumman's 22nd cargo mission to the space station under a multi-billion-dollar commercial resupply contract with NASA. All but one have successfully reached the station. This mission has taken on greater importance than a typical cargo delivery flight after engineers discovered damage to a Cygnus spacecraft that was supposed to launch earlier this year.