Sensors Result in Delta IV Heavy, Falcon 9 Launch Scrubs

Launches of Delta IV Heavy and Falcon 9 rockets from Florida’s Space Coast were aborted with only seconds to go before liftoff less than 10 hours apart.

The countdown of an United Launch Alliance (ULA) Delta IV Heavy was stopped 7 seconds before a planned 11:54 p.m. launch on Wednesday after a sensor detected an unidentified fault. Crews safed the vehicle on its launch pad at the Cape Canaveral Air Force Station.

The massive rocket is carrying the NROL-44 spy satellite for the National Reconnaissance Office. ULA has not set a new launch date.

It was the sixth scrub or launch delay for the ULA booster since Aug. 27. Five of the delays occurred due to technical problems, the other resulted from weather.

Less than 10 hours later, an “out of family” ground sensor aborted the countdown of SpaceX’s Falcon 9 rocket from NASA’s Kennedy Space Center only 18 seconds before a planned 9:17 a.m. EDT liftoff.

The booster is carrying 60 spacecraft for the company’s Starlink satellite broadband constellation. SpaceX has not announced a new launch date for the flight.