Boeing Starliner’s first astronaut flight halted at last minute after yet another issue

Countdown for Starliner capsule was halted at 3 minutes and 50 seconds by the computer system that controls final minutes before liftoff

A last-minute problem cancelled Saturday’s launch attempt for Boeing’s first astronaut flight, the latest in a string of delays over the years.

Two NASA astronauts were strapped in the company’s Starliner capsule when the countdown automatically was halted at 3 minutes and 50 seconds by the computer system that controls the final minutes before liftoff.

With only a split second to take off, there was no time to work the latest trouble and everything was called off. It was not immediately clear why the computers aborted the countdown.

Launch controllers were evaluating the data, said United Launch Alliance’s Dillon Rice. But it’s possible the team could try again as soon as Sunday.

Astronauts Butch Wilmore and Suni Williams remained in their capsule seats, as they awaited technicians to help them out.

Boeing's Starliner capsule atop an Atlas V rocket stands ready at Space Launch Complex 41 at the Cape Canaveral Space Force Station (AP)

The first launch attempt on 6 May was delayed for leak checks and rocket repairs.

NASA wants a backup to SpaceX, which has been flying astronauts for four years.

AP contributed to this report