By any chance would anyone have a photo of either of these H-21C's, 57-2610 and/or 57-2611, either from their time in the MASDC or in the case of 57-2610 at Hill AFB in the 1970's? Both were used as test helicopters for the twin gas turbine engine conversion but later restored to their standard Wright R-1820 powerplant.
Thanks,
Colin