Your behavior appears to be a little unusual. Please verify that you are not a bot.

GPS III launch aborted with 2 seconds to spare

October 1, 2020  - By

UPDATE (Oct. 5): Elon Musk, SpaceX founder and CEO, said a Falcon 9 launch was halted Friday night due to an “unexpected pressure rise in the turbomachinery gas generator,” referring to a part in the rocket’s Merlin engines, reports SpaceflightNow.

SpaceX has not yet set a new launch date. Another planned launch, for a Starlink satellite, was also aborted.

UPDATE (Oct. 3): Only two seconds before launch, SpaceX aborted the scheduled launch of the fourth GPS III satellite on Oct. 2. SpaceX has not yet announced a new launch window, or stated the reason for the cancellation.

One Twitter user responded with video of the launch up to the moment it was cancelled.

(Oct. 1) The U.S. Space Force’s newest GPS III satellite, Space Vehicle 04 (GPS III SV04), rolled out to Cape Canaveral’s Space Launch Complex 40 on Sept. 27. Originally scheduled for launch Sept. 30, then Oct. 1, the satellite is now slated to launch 9:43 p.m. EDT on Oct. 2 (01:43 a.m. UTC on Oct. 3).

The launch was delayed because of a “traffic jam” at the launchpad. According to Spaceflight Now, SpaceX initially rescheduled the GPS launch for Wednesday night after a Delta 4 launch was delayed to Tuesday. After the Delta 4-Heavy’s scrub Tuesday, SpaceX announced the GPS launch would be pushed back to Friday, when there is a 15-minute launch window available opening at 9:43 p.m. EDT (0143 GMT Saturday, Oct. 3).

The Lockheed Martin-built GPS III SV04 is scheduled to launch aboard a SpaceX Falcon 9 rocket — the third National Security Space Launch (NSSL) mission on a Falcon 9 rocket, the second U.S. Space Force (USSF) first-stage booster recovery, and the sixth USSF launch on Sept. 30. The 15-minute launch window opens at 9:51 p.m. EDT. A live feed will begin 20 minutes before the launch and conclude approximately 45 minutes afterward. A simulcast of the broadcast can be viewed at

“The GPS III program office in partnership with our contract teammates continue to push the envelope on the capabilities they deliver to users, both civil and military around the globe. Our latest GPS III satellites’ nearly 70 percent digital payload provides the U. S. Space Force with greater operational flexibility and cutting edge capabilities while continuing to support legacy users,” said Cordell DeLaPena, Air Force program executive officer for SMC’s Space Production Corps.

GPS III SV04 will be launched to augment the current GPS constellation comprised of 31 operational spacecraft. GPS satellites operate in Medium Earth Orbit (MEO) at an altitude of approximately 20,200 km (12,550 miles) in six orbital planes. Each satellite circles the earth twice per day. GPS is the premier space-based provider of positioning, navigation, and timing services for more than four billion users worldwide. This latest generation of GPS satellite boasts a 15-year design life — 25 percent longer than the previous generation of GPS satellites on orbit.

GPS III brings new capabilities to users such as the new L1C civilian signal, which opens the window for future interoperability with international satellite navigation systems.

“Our GPS III team is excited to be here once again. Less than 3 months ago, we successfully launched GPS III SV03. Since then, the team has successfully delivered the satellite to its final orbit, performed on-orbit testing and delivered the satellite to operations, while executing a mature satellite production line. I can’t be more proud of everyone involved in this mission,” said Col. Edward Byrne, Medium Earth Orbit Space Systems Division chief. “The launch of GPS III SV04 will continue to modernize our GPS constellation by increasing our capabilities with advanced features for both our civil and military users across the world.”

A Falcon 9 with GPS III SV 04 encapsulated inside the payload fairing the stands vertical on the pad at Cape Canaveral’s Space Launch Complex 40 in preparation for launch. (Photo: USAF/SpaceX)

A Falcon 9 with GPS III SV 04 encapsulated inside the payload fairing the stands vertical on the pad at Cape Canaveral’s Space Launch Complex 40 in preparation for launch. (Photo: USAF/SpaceX)

About the Author: Tracy Cozzens

Senior Editor Tracy Cozzens joined GPS World magazine in 2006. She also is editor of GPS World’s newsletters and the sister website Geospatial Solutions. She has worked in government, for non-profits, and in corporate communications, editing a variety of publications for audiences ranging from federal government contractors to teachers.