Sunita Williams 3rd flight to space scrubbed, Nasa announces new date

Indian-origin astronaut Sunita Williams was suited and ready to launch on her third flight to space on Tuesday, when the first crewed flight of Boeing's Starliner spaceship was dramatically called off around two hours before launch after a new safety issue was identified.

Astronauts Butch Wilmore and Suni Williams were strapped in their seats preparing for liftoff when the call for a "scrub" came, in order to give engineers time to investigate unusual readings from an oxygen relief valve on the second stage of the rocket.

Nasa said that the launch was scrubbed as teams evaluated an oxygen relief valve on the Centaur Stage on the Atlas V.

The Atlas V rocket is manufactured by the United Launch Alliance, which said that the decision was taken due to observation on a liquid oxygen self-regulating solenoid relief valve on the Centaur upper stage. "The team needs additional time to complete a full assessment," ULA said in an update.

Meanwhile, Nasa has announced that Boeing Starliner with the two astronauts will attempt to launch atop the ULA rocket on May 10.

"We are targeting no earlier than Friday, May 10, for the launch of the agency’s Boeing Crew Flight Test to the International Space Station, pending resolution of the technical issue that prevented the May 6 launch attempt," Nasa said.

It added that the delay allows teams to complete data analysis on a pressure regulation valve on the liquid oxygen tank of the Atlas V rocket‘s Centaur upper stage and determine whether it is necessary to replace the valve. The Starliner spacecraft, named Calypso, can fly autonomously or be steered manually.