Did the Air Force B-2 bomber make it's first flight prior to the public first flight July 17, 1989?

Answer 1

Of course! Many times, actually!

Virtually all military aircraft -- especially combat aircraft -- are designed, built, and tested under secret conditions. The first public demonstration is long after all of the first secret test flights.

Some aircraft are actually in active service for years before the public unveiling. The SR-71 and F-117 are two excellent examples of this, and it's highly likely that the B2 was in active service long before the public was made aware of its existance.

Answer 2

No. Since it was built at the Northrop plant in Palmdale, Califormia, a secret flight of an aircraft that size would have been impossible. That is why the B-2 was revealed to the world several days before its highly publicized November 22, 1988 roll-out. It's interesting to note that the test pilots already had hundreds of hours in the B-2 flight simulator, and that the airplane flew exactly as predicted.