Tracking the CH-54 with its high-off-the-ground rotor, prior to the appearance of electronic trackers was a maintenance chore: six different crayon colors on the blade tips, then holding a long pole, bottom on the ground and easing the flag suspended on the high end , ever so slowly into the edge of the rotor path. Definition of PIA.
At least with the CH-47 aft rotor you only had to deal with three colors.
Last edited by JohnDixson; 24th June 2025 at 11:34.
Reason: CH-47 note