Updated on Thursday, July 02, 2009, 08:44 IST

Washington, July 02: The US space shuttle Endeavour has cleared a test for potentially harmful hydrogen gas leaks that twice delayed its high-profile launch, NASA has said.

Engineers from the US space agency seemed to have successfully repaired the external fuel tank of the shuttle, which is waiting to embark on its final mission to the International Space Station (ISS) with a seven-member crew.

To test Endeavour's flight worthiness its massive orange fuel tank was filled with 526,000 gallons (two million litres) of liquid hydrogen (80 percent) and liquid oxygen (20 percent), as takes place on the launch day.

During the test "no abnormal gaseous hydrogen leaks were detected," NASA said yesterday, which increases chances that Endeavour will be set for a launch on July 11 at 2339 GMT.

"There were absolutely no leak indications whatsoever noted on the two leak detectors," said launch director Pete Nickolenko.

"We'll continue to look at the data, and our next step is to move toward launch."

NASA officials were set to provide details on the new launch date and the test results later yesterday.

After the tank was 98 percent full, it successfully entered "topping" mode -- the phase in which the June 13 and June 17 leaks had occurred -- where a valve at the top of the tank cycled to disperse excess gaseous hydrogen through a vent system that carries it safely away from the launch pad.

Bureau Report