WSJ: SpaceX not responsible for Zuma spy satellite sinking

According to The Wall Street Journal, SpaceX is not to blame for the loss of the secret Zuma satellite. A part modified by aircraft manufacturer Northrop Grumman to decouple the Zuma satellite in space probably didn’t work.

According to The Wall Street Journal, several industry and government officials who have investigated the satellite’s dumping into the ocean have said Northrop blames Grumman for the failed mission.

A payload adapter known as Northrop Grumman-customized, a component to ensure that the Zuma satellite was decoupled from the launch vehicle in space, has not worked properly, the sources said. Eventually, the satellite would have detached from the second rocket stage, but that happened at an altitude where the satellite would have been beyond salvage.

It had previously been speculated that this component was the reason for the satellite’s loss, partly because SpaceX quickly announced that the Falcon 9 rocket had been operating normally. Northrop Grumman, which also builds the James Web Space Telescope, is said to have successfully tested the component on the ground three times.

The aircraft manufacturer, who also built the Zuma satellite, deliberately modified the payload adapter, because its unique design would have made Zuma quite vulnerable to shock and vibration. Northrop Grumman therefore modified the payload adapter so that no explosive bolts were used.

Little is still known about Zuma, a spy satellite built for the US government and launched on January 7 by a Falcon 9 rocket. Both Northrop Grumman and the Pentagon have declined to comment.