Top Secret (B-29)

Top Secret was the name of a B-29 Superfortress (B-29-36-MO 44-27302, Victor number 72) modified to carry the atomic bomb in World War II.

Airplane history
Assigned to the 393d Bomb Squadron, 509th Composite Group, it was one of 15 Silverplate B-29s used by the 509th. Top Secret was built at the Glenn L. Martin Aircraft Plant at Omaha, Nebraska, as a Block 35 aircraft. It was one of 10 modified as a Silverplate and re-designated "Block 36". Delivered on April 2, 1945, to the USAAF, it was assigned to crew B-8 (1st Lt. Charles F. McKnight), aircraft commander) and flown to Wendover Army Air Field, Utah. It left Wendover on June 5, 1945, for North Field, Tinian and arrived June 11.

It was originally assigned the Victor (unit-assigned identification) number 2 but on August 1 was given the large 'A' tail markings of the 497th Bomb Group as a security measure and had its Victor changed to 72 to avoid misidentification with actual 497th BG aircraft. It was named Top Secret and its nose art applied after the atomic bomb missions.

While at Tinian, McKnight and crew B-8 flew Top Secret on 13 practice bombing missions and four combat pumpkin bomb missions against Japanese industrial targets at Otsu, Yokkaichi, Ube, and Toyoda. The plane flew two other pumpkin bomb missions, to Taira (1st Lt. Joseph E. Westover and crew A-4) and Yokkaichi (Capt. Claude Eatherly and crew C-11).

On August 6, 1945, it was assigned as the strike spare for the first atomic bomb mission but did not complete the mission, landing at Iwo Jima as previously planned when the B-29 Enola Gay was able to complete its assignment.

In November 1945 it returned with the 509th to Roswell Army Air Field, New Mexico. From March to August 1946 it was assigned to the Operation Crossroads task force, then rejoined the 509th BG at Roswell. In June 1949 Top Secret was transferred to the 97th Bombardment Group at Biggs Air Force Base, Texas, then sent to Tinker Air Force Base in April 1950 for modification to TB-29 specifications at the Oklahoma City Air Materiel Area.

Subsequent assignments were to:
 * 2nd Radar Calibration Squadron, Elmendorf Air Force Base, Alaska (March 1953), and the
 * 5025th Maintenance Group, Elmendorf AFB (August 1953).

In September 1953 it was sent to the 3040th Aircraft Storage Group at Davis-Monthan Air Force Base, Arizona, where it was scrapped in July 1954.

Hiroshima mission crew
Crew B-8 (regularly assigned to Top Secret)
 * Capt. Charles F. McKnight, airplane commander
 * 2nd Lt. Jacob Y. Bontekoe, co-pilot
 * 2nd Lt. Jack Widowsky, navigator
 * 2nd Lt. Franklin H. MacGregor, bombardier
 * 1st Lt. George H. Cohen, flight engineer
 * Sgt. Lloyd J. Reeder, radio operator
 * T/Sgt. William F. Orren, radar operator
 * Sgt. Roderick E. Legg, tail gunner
 * Cpl. Donald O. Cole, Assistant engineer, scanner

Other aircraft named Top Secret
An FB-111A strategic bomber of the USAF, serial 69-6513, carried the name Top Secret on its nosewheel doors, during its service with both the 509th Bomb Wing at Pease Air Force Base, New Hampshire, and the 380th Bomb Wing at Plattsburgh Air Force Base, New York, in the 1970s and 1980s.