Aircraft
B-21 Completes Preliminary Design Review, U.S. Air Force Says
The secretive bomber program is keeping to its schedule and budget, according to Gen. Stephen Wilson, Air Force vice chief of staff.
The U.S. Air Force has closely guarded details of development program for the B-21 bomber, seen here in an artist's rendering.
The U.S. Air Force has closely guarded details of development program for the B-21 bomber, seen here in an artist's rendering.

The secretive B-21 bomber program recently completed a preliminary design review, according to a senior U.S. Air Force officer, who said the service is satisfied with the program’s progress. The comments provided one of the first markers of the program status since the Air Force awarded Northrop Grumman a contract to begin engineering and manufacturing development (EMD) in October 2015.