WASHINGTON — The Federal Aviation Administration has denied a payload review for in-space transportation company Momentus, meaning the company will miss its second opportunity to launch its first tugs.

In a May 11 filing with the Securities and Exchange Commission, Momentus said the FAA’s Office of Commercial Space Transportation notified the company May 10 that it had denied the company’s application for a payload review, part of the FAA’s launch licensing process. Momentus sought the review in order to be part of a SpaceX dedicated rideshare launch scheduled for June. Denials of payload reviews by the FAA are rare.

The FAA rejected the application “based on the FAA’s finding that its launch would jeopardize U.S. national security,” the company said in the filing. “According to the letter, during an interagency consultation, the FAA was informed that the launch of Momentus’ payload poses national security concerns associated with Momentus’ current corporate structure.”

Momentus had stated in earlier filings that the Defense Department had raised “national security and foreign ownership concerns” about the company during an interagency review that is part of the FAA payload approval process. That led to the FAA failing to grant an approval in time for the company’s Vigoride-1 tug to launch on SpaceX’s Transporter-1 rideshare mission that launched in January.

As recently as last week, company executives remained hopeful that the FAA would approve Vigoride-1 for launch in June, along with a second, larger tug, Vigoride-2. The tugs, which will deploy several cubesats after release from the Falcon 9, are ready for launch, Rob Schwarz, chief technology officer of Momentus, said in a May 4 webinar. “It’s ready to go and it will, assuming we get all our licenses,” he said.

Momentus has been working to address the national security concerns raised by the Defense Department, including agreeing to a voluntary review of the company by the Committee on Foreign Investment in the United States. Mikhail Kokorich, the Russian co-founder of the company, stepped down as chief executive in January, and he and Brainyspace LLC, a firm owned by co-founder Lev Khasis and his wife, agreed in March to divest their shares within three years.

The company noted in its SEC filing that the FAA’s rejection of its payload review application is not permanent. “The letter further states that the FAA understands that Momentus is undergoing a process that may resolve the national security concerns, and that the FAA can reconsider a payload application when that process has been completed,” it stated. However, it acknowledged that it will not be able to launch the first two Vigoride tugs in June.

The letter comes as a special-purpose acquisition company (SPAC), Stable Road Acquisition Corporation, is working to win shareholder approval for a three-month extension of the deadline to complete a deal with Momentus. The company needs 65% of shareholders to agree to extend that deadline from May 13 to Aug. 13.

Stable Road said in a May 10 press release that 62% of shareholders had voted in favor of the extension so far. If Stable Road does not hit the 65% threshold by the May 13 deadline, the deal to merge with Momentus will be off and the SPAC liquidated to its shareholders at $10.03 per share. Shares in Stable Road closed at $10.40 per share on the Nasdaq exchange May 11.

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...