A move by Virgin Galactic to resume test flights has been labeled “highly positive” by respected US analysts Bernstein, boosting optimism commercial flights could begin by early 2022. The space tourism venture backed by British billionaire Richard Branson had originally scheduled the test for February but it was delayed after a rocket in the spaceship, VSS Unity, misfired during a December flight. READ: AirNZ, US lawmakers spearhead renewed push for biofuel This was attributed to an electromagnetic interference issue that prompted an onboard computer to halt the ignition of the motor. Galactic then announced at its quarterly results that a May 22 test flight had been delayed because of a maintenance issue in the tail of  VMS Eve, the mothership designed to carry Unity to 50,000ft. But the company announced this week that a test of Unity would be conducted Saturday, May 22, subject to technical checks and weather. Virgin Galactic chief executive Michael Colglazier said a detailed inspection of Eve had cleared the system for the test flight. “We had worried that a longer delay in test flight schedule would create risks that the timeline for commercial flights would move back,’’ Bernstein said in a note. “It also raised questions on structural maintenance for the mothership “Those risks are lower now, with the prospects for a successful test flight on Saturday.” The test flight will carry two pilots, as well as research payloads, and aims to confirm that remedial work carried out after the December test flight is effective. A successful mission will be followed by three others: the first carrying a full crew of Virgin Galactic employees; a second that will include Branson himself; and a third performed with the Italian Air Force for astronaut training and to demonstrate microgravity research. The project already has 600 customers on its waiting list and newly-priced tickets are expected to be released after the Branson flight. “We see Virgin Galactic as potentially a highly profitable business if unusual risks associated with space flight can be safely minimized,’’ Bernstein said. .