A GPS 3 satellite atop a SpaceX Falcon 9 rocket sits at Launch Complex 40 at Cape Canaveral Air Force Station, Florida. Credit: SpaceX

Update: SpaceX said Wednesday morning it needed more time to evaluate the cause of Tuesday’s launch scrub. “Standing down from today’s launch attempt of GPS III SV01 to further evaluate out of family reading on first stage sensors; will confirm a new launch date once complete,” SpaceX tweeted at 6:32 a.m. Eastern Wednesday.

WASHINGTON — SpaceX on Tuesday scrubbed the Falcon 9 launch of the Air Force’s first GPS 3 satellite. The next opportunity is Wednesday morning but the commander of the 45th Space Wing said Tuesday afternoon that he was “not confident” Falcon 9 will be cleared by then for a second attempt.

“We saw some sensors today that gave us a little bit of an alarm so we decided to hold the launch at that time,” Air Force Brig. Gen. Douglas Schiess said during a media teleconference call Tuesday afternoon. Also on the call were Air Force Secretary Heather Wilson and Lt. Gen. John Thompson, the commander of the Air Force Space and Missile Systems Center.

The Air Force is forecasting acceptable weather Wednesday morning at Cape Canaveral, Florida, but Schiess said the Air Force and SpaceX were working through some technical issues that could further delay the launch.

SpaceX spokesman James Gleason did not respond to an email seeking comment. In a statement immediately after Tuesday’s scrub, SpaceX blamed sensor readings for the scrub and said the launch team would try again Wednesday. “SpaceX team called a hold due to an out of family reading on first stage sensors,” SpaceX said via Twitter on Tuesday. “Vehicle and payload remain healthy; next launch attempt is tomorrow at 9:07 EST, 14:07 UTC.”

During a media teleconference about four hours after Tuesday’s scrub, Schiess expressed doubt that Falcon 9 would lift off Wednesday morning. “I can’t say we’re confident on that right now,” Schiess said. “We’re holding tomorrow’s schedule. But we’re not confident at this point.”

Schiess did not go into detail about why he wasn’t confident that Falcon 9 would be ready by Wednesday morning for a second launch attempt.

“We are now working with General Thompson’s folks and SpaceX to see whether we can launch tomorrow,” Schiess said. “When we get ready, and the rocket’s good, we’re looking forward to a great launch of the first EELV launch for SpaceX.”

Although SpaceX has launched national security payloads before — notably the Air Force’s X-37B spaceplane and a classified payload for the National Reconnaissnce Office both in 2017 — the GPS 3 launch is the first mission the Air Force awarded to SpaceX under the Evolved Expendable Launch Vehicle (EELV) program established in the 1990s to develop the Atlas 5 and Delta 4 rockets and procure national security launches. The contract was awarded to SpaceX in April 2016. SpaceX has an additional four GPS 3 launches on contract, all of which will be launched on Falcon 9.

“We were hoping to see the launch of the GPS satellite this morning,” Wilson said during Tuesday’s post-scrub conference call with reporters. “It’s certainly on my bucket list. I hope to be able to come back and see a launch. But I also give a lot of credit to the folks who are running the operation, that safety and mission assurance come first, and they made the right decision this morning.”

Wilson was at Cape Canaveral to watch the launch with Vice President Mike Pence. They both spoke Tuesday at NASA’s Kennedy Space Center where Pence announced that President Donald Trump had issued the order to establish a U.S. Space Command.

Thompson said that regardless of when the launch takes place, the Air Force is encouraged that SpaceX is now competing for military launches. “For the first time in the history of the EELV program, we have competition back,” he said.

“This opportunity for SpaceX to compete and win this mission — and then put up such as a significant payload as our very first GPS 3 satellite — is tremendously significant not just for SpaceX and for the satellite provider Lockheed Martin but for the United States,” Thompson added. “Our launch industrial base, particularly for big rockets, is very robust right now.”

Sandra Erwin writes about military space programs, policy, technology and the industry that supports this sector. She has covered the military, the Pentagon, Congress and the defense industry for nearly two decades as editor of NDIA’s National Defense...