On this day 4 decades ago, the first Chinook was delivered to Royal Air Force.
Boeing: Celebrating 40 years of Chinook
(photo courtesy of Boeing)
A decade and half earlier, the late Eric ‚Winkle‘ Brown went to Boeing Philadelphia to fly the YCH-47A prototype (62/63??) as MoD looking at heavy lift requirement. But it did not materialise
cheers