In yet another blow for Sir Richard Branson's space tourism company, Virgin Galactic has been forced to delay its first commercial space mission by several weeks. This comes after it discovered a possible manufacturing flaw.

According to reports, the latest issue involves a third-party supplier which flagged a potential defect in a component of the flight-control system it had provided.

In a statement, Virgin Galactic said that the delay was unrelated to the Federal Aviation Authority's (FAA) ongoing investigation of Branson's flight on July 11.

It means the 'Unity 23' research mission with the Italian Air Force, which was originally scheduled for September or early October, will now not take place until the middle of next month at the earliest. 

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This delay would be a big blow for Branson, whose billionaire rival Elon Musk is set to launch the world's first all-civilian crew into space on SpaceX's Crew Dragon capsule this week.

Inspiration 4's four-man team, which won't include Musk, will orbit the Earth for three days. 

In a statement about the potential manufacturing problem Virgin Galactic said: 'At this point, it is not yet known whether the defect is present in the company's vehicles and what, if any, repair work may be needed.'

Meanwhile, Branson has said he anticipates offering paid flights on a 'regular basis' next year, which will come as a relief for the 600 'future astronaut' ticket holders who have waited over a decade for the opportunity to go into space.

In July this year, Branson flew to the edge of space himself, beating another billionaire — Amazon founder Jeff Bezos — by nine days.

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At the time all seemed to go as planned, with the mothership taking off as expected, and the spaceplane being released at 50,000ft to continue its 40 mile journey to space, before safely gliding back to land on a runway at Spaceport America. 

Speaking to the New Yorker, the Federal Aviation Authority (FAA), which oversees commercial air and spaceflight in the US, confirmed the spaceplane 'deviated from its Air Traffic Control clearance' and did so for about a minute and 41 seconds.

In a statement on the FAA investigation, Virgin Galactic said that 'the flight did drop below the altitude of the airspace', but confirmed this was 'for a short distance and time (1 minute and 41 seconds) before re-entering restricted airspace.' 

Bezos and Branson have backed space missions without professional astronauts onboard. Both of these flights were 'suborbital' and lasted just a few minutes. 

Mission commander Jared Isaacman, the American founder and chief executive of e-commerce firm Shift4 Payments, will be joined by three fellow spaceflight novices on the trip.