WASHINGTON — Boeing’s KC-46 Tanker recently last week completed aerial refueling initial airworthiness, the latest step on the road to full air refueling capability.

The test plane's 20th flight on Thursday marked the completion of a series of flight tests that validated the plane's initial airworthiness to conduct aerial refueling operations, Boeing spokesman Charles Ramey told Defense News.

During the flights, t The team conducted what is called "free air stability" testing and worked to validate the plane’s aerodynamic model during the flights, Ramey said.

This The initial airworthiness validation step is the first of two major milestones necessary for the new tanker to conduct its core mission, aerial refueling, according to Boeing spokeswoman Caroline Hutcheson.  

The next step is "fuel dock" testing, in which the test team validates the fuel transfer control functions, she said.

Soon after completing fuel dock, Boeing will begin conducting full refueling flight tests with six kinds of different receiver aircraft, including another KC-46, Ramey said.

"It is positive progress and a major block complete in getting us to the first refueling flights that support Milestone C," Ramey said.

The latest news is yet another sign that Boeing’s KC-46 is on track after several significant delays. First flight, which was achieved Sept. 25, has been was postponed repeatedly since 2014. The latest delay was caused when a mislabeled chemical was mistakenly loaded into the aircraft’s refueling line during testing.

Boeing is planning for a Milestone C decision, formal approval from the Pentagon for production, between January and April 2016. The company must deliver 18 full-up tankers by August 2017.

Email: lseligman@defensenews.com

Twitter: @laraseligman

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