Virgin Galactic shares plummet after company says it will delay commercial spaceflights until Q4 2022

• Virgin Galactic said Thursday it has delayed its commercial spaceflights until Q4 2022.
• The delay is not connected to a recent probe by the FAA, which cleared the company to fly.

Virgin Galactic said in a press release Thursday that it will delay the start of its commercial spaceflight operations until the fourth quarter of 2022.

Virgin had planned to launch its first commercial test flight, Unity 23, in October, but the company said testing results of new materials prompted it to make changes to its timeline.

"Recent laboratory-based tests flagged a possible reduction in the strength margins of certain materials used to modify specific joints, and this requires further physical inspection," Virgin said.

The company said that while the test results didn't impact any of its vehicles, it plans to undertake "further analysis" to determine whether any additional work will be required to ensure the vehicles meet all "strength margin" requirements.

As a result, Virgin said it decided that the "most efficient and expedient path to commercial service" is to begin its "enhancement program" - which could take up to 10 months, Virgin told CNBC - before Unity 23 flight, and continue its testing in parallel.

Virgin said the delay is not related to the Federal Aviation Administration's recent investigation into the company following a mishap that occurred during Virgin founder Sir Richard Branson's flight in July. The FAA cleared Virgin to fly again in September.

Virgin's stock tumbled more than 14% after the market closed Thursday following its announcement.