Billionaire Richard Branson's Virgin Galactic Holdings Inc said on Monday it was evaluating the timing of its next flight test, sending shares down 9.4% in extended trade.

"Following Eve's last post slide inspection, we tagged a potential wear and tear issue as requiring further evaluation and analysis to see if any additional action is necessary," said Michael Moses, president of the company's space missions & safety, on a post earnings conference call.

"We continue to make strides towards our strategic objectives and have solid momentum as we focus on completing our flight test program," Chief Executive Officer Michael Colglazier said in a statetment.

Virgin Galactic, which delayed its quarterly results by about a week, said total future astronauts remained at about 600, as of March 31.

It also posted a first-quarter loss of $130 million, compared to a $377 million net loss last year.

  - Reuters