How many planes flew in each atomic bombing mission over Japan and what were their types and roles in the mission?

Three B-29 were flown in each operation on 6 of august 1945 and the 9th, over Hiroshima and Nagasaki. One plane had the nuclear device, another dropped data collection instruments, and the last had cameras.
The fact that most of the instruments were on parachutes caused some survivors to incorrectly report that the bomb itself was on a parachute.