On July 27, 1945, Costello and his crew flew the airplane from Wendover to Kirtland Army Air Field, Albuquerque, New Mexico, accompanied by another 509th B-29 and one from the Manhattan Project test unit at Wendover (216th AAF Base Unit). There each loaded one of three Fat Man atomic bomb assemblies (without the plutonium core, which had left the day before by courier on one of the 509th CG's C-54 Skymaster transports) in its bomb bay for conveyance to Tinian.
The three bombers flew to Mather Army Air Field, California, on July 28, and took off for Hawaii on July 29. During takeoff from Mather, a panel door on Laggin' Dragon enclosing the life raft compartment opened and ejected the raft, which wrapped around the empennage and impeded the B-29's elevators. The aircraft struggled to stay aloft but the pilots managed to return safely to Mather. After removing and replacing some major tail assemblies, Laggin' Dragon and its cargo continued to Hawaii, finally reaching Tinian on August 2.
It was assigned the square P tail identifier of the 39th Bomb Group as a security measure and given Victor (unit-assigned identification) number 95 to avoid misidentification with actual 39th BG aircraft. The airplane was named while still at Wendover but the nose art was not applied until after the atomic missions. It arrived too late to participate in other combat operations and participated in two practice flights subsequent to the atomic attacks. On August 9, 1945, as part of the second atomic bomb mission, it was flown by another crew as the weather reconnaissance aircraft for the secondary target of Nagasaki.
Three FB-111A strategic bombers of the USAF 509th Bomb Wing, serials 68-0269, 68-0274 and 68-0284, carried the name and original nose art of Laggin' Dragon on their nosewheel doors while based at Pease Air Force Base, New Hampshire, in the 1970s and 1980s.
Sources
Campbell, Richard H., The Silverplate Bombers: A History and Registry of the Enola Gay and Other B-29s Configured to Carry Atomic Bombs (2005), ISBN0-7864-2139-8