Engine run-ups were recently brought to mind when I flew on a DC-3 in Alaska. Before we took off, we sat just off the end of the runway and ran up both engines, one at a time, to full power, then back to idle. Then we proceeded to turn onto the runway for take-off. I remember doing this many years ago on DC-6, DC-7, Martin 4-0-4, and Convair 440 aircraft. Why was it necessary for piston aircraft to do this, while turboprop and jet aircraft do not?
Fly Eastern's Golden Falcon DC-7B