Your grandfather, 2nd LT Herbert W. Mackey, and his crew reported to the 493rd BG on 28 August 1944 and they were assigned to the 863rd BS. At that time, the crew included:
2nd LT Herbert W. Mackey - pilot
2nd LT Richard L. McClain, Jr - co-pilot
2nd LT Jacob Kinn - navigator
2nd LT Laverne J. Dempsey - bombardier
Cpl Michael J. Lasalata - flight engineer
Cpl Ralph L. Peshek - gunner
Cpl Elmer W. Fuzzell - flight engineer
Cpl Hugh C. Price - gunner
Cpl Roderick R. Reynolds - gunner
Your grandfather flew 35 mission. On 29 September 1944, Herbert was promoted to 1st LT. On 4 February 1945, he was transferred to the 5th Emergency Rescue Squadron located at Halesworth, Suffolk. When he transferred, he took with him an entirely new crew.
I do have additional information that is too hard to share through this web page. Contact me directly at my e-mail address (in my signature below) and I would be more than happy to expand on the above information.
David Schmitt email@example.com
son of 1st LT Donald J. Schmitt, USAAF, co-pilot
assigned to 493rd BG/863rd BS at Debach, England
from Nov 1944 thru May 1945