The first Northrop Grumman/EADS North America A330 for the U.S. Air Force has been sent to Germany in preparation for a cargo modification, though work stopped on the project before it got under way.

The first developmental KC-45, called D-1, was sent to Airbus's passenger-to-cargo conversion facility in Dresden March 4. Work on the cargo modification was to begin March 12.

However, Northrop Grumman/EADS's rival, Boeing, protested the $1.5-billion developmental contract award. Per standard procedure, the Air Force issued a stop-work order to Northrop Grumman on March 14, and work on the D-1 conversion came to a halt before it began, according to a company official.

The Government Accountability Office has 100 days to review it and a motion from the Air Force to dismiss some of Boeing's protest claims.

The Air Force obligated $60 million to the winning team prior to the protest.

Northrop Grumman has been coy about what work is under way, largely because of Boeing's protest. The company only acknowledged the transfer of the aircraft late last week.

The cargo conversion is the first in a series of steps to modify the aircraft to fill the Air Force's KC-45 requirements. The aircraft will get its refueling systems at CASA's plant Madrid and later its military specific items, like defensive systems, will be added at Northrop Grumman's Melbourne, Fla., facility.

The first test flight was slated for February 2010 prior to the protest.

More photos of D-1 arriving in Dresden are posted at Aviation Week's Ares defense blog.