44th Bombardment Group

 is a bomber group of the pre-War United States Air Force. The tail code for the 44th Bombardment Group can be seen on the tail of the Crashed B-29 in Lake Mead.

Background
On July 21st 1948, a crew from the 44th would crash a B-29 Superfortress in Lake Mead while performing atmospheric research. The crew would be safely recovered, but the B-29 would sink to the bottom of the lake where it would become an object of interest for a local tribe named the Boomers.

Links

 * on Wikipedia

Appearances
The tail code of the appears in Fallout: New Vegas.