Boeing KC-46A tanker uses modified boom to pass fuel to C-17: U.S. Air Force

FARNBOROUGH, England (Reuters) - Boeing Co’s KC-46A refueling plane has successfully transferred fuel to an F-16 fighter jet and a C-17 cargo plane using a modified boom outfitted with new hydraulic pressure relief valves, the U.S. Air Force said on Wednesday.

The logo of Dow Jones Industrial Average stock market index listed company Boeing (BA) is seen in Los Angeles, California, United States, April 22, 2016. REUTERS/Lucy Nicholson

“This week’s successful tests show the boom axial loads hardware fix, designed by Boeing engineers, is performing as expected to alleviate the loads,” the Air Force said in a statement on its website.

Boeing was forced to modify the refueling boom, delaying the $49 billion program, after earlier tests showed the fuel transfer had put too much pressure on the boom, a long pipe that extends out of the back of the aircraft.

The company said a KC-46A tanker equipped with the modified boom transferred 2,200 pounds of fuel to the C-17 cargo plane during a four-hour flight on Tuesday.

“We’ve now completed more than 850 flight test hours with five aircraft,” a Boeing spokeswoman said.

Air Force Secretary Deborah James was encouraged by the results of the latest testing. “The KC-46 program continues to move forward, making important progress that will get this vital capability into the hands of the warfighter,” she said.

The Air Force said the KC-46A tanker refueled the F-16 on July 8. It must still pass fuel to an A-10 Thunderbolt later this month to complete tests required before the new aircraft can move into production, the Air Force said.

Once that test is completed, the Air Force said it would ask the Pentagon to approve contract awards for the first two batches of production jets, a total of 19 aircraft.

“While it took some time, this week’s results confirm my confidence the Boeing team will get this figured out. It’s reassuring to see the program take this important step toward the production decision in August,” said Air Force Chief of Staff General Dave Goldfein.

Boeing’s new defense chief Leanne Caret told reporters on Sunday the company was seeing positive results with its boom testing. She said the hardware changes did not amount to a redesign of the boom, and would not require additional certification.

The U.S. Air Force last month said it would seek compensation from Boeing for a five-month delay in delivering KC-46A Pegasus aerial refueling tanker aircraft.

Boeing now expects to delivery a first batch of 18 tankers in January 2018 instead of August 2017, and says the planes will lack some capability until October 2018.

Reporting by Andrea Shalal; Editing by Mark Potter