S97 Raider

[Lonewolf_50]

CRM issues with that one collective to be shared by two:

I have the controls
- No, I have the controls
-- No, I have the controls
--- Voice from the back "Get a room, you two!"

[Robbo Jock]

Must have been a riot to track and balance those MR blades.

Would appear you're not wrong. From the Wikipedia article on the R-4:

​​​​​​​The helicopter was difficult to fly. The aircraft's blades were made of wood ribs around a steel spar and covered with doped fabric. The blades were difficult to keep rotating in the same plane and vibrated excessively. The cyclic made continuous small orbits, vibrating continuously. There was no governor to control rotor speed, and the pilot had to correlate the throttle continuously with collective pitch inputs. The Chicago Tribune reported on Carle's efforts to transport the wounded. They wrote that the "control stick shakes like a jackhammer, and the pilot must hold it tightly at all times. Should he relax for even a minute the plane falls out of control. Pilots of regular planes say it's easy to identify a helicopter pilot – he has a permanent case of the shakes."

​​​​​​​"permanent case of the shakes"

[JohnDixson]

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.

[wrench1]

Did some looking and found this on the R-4 blades. I knew they were fabric covered but having each blade a unique part must have been an adventure to keep flying straight. The original "good old days."
There's also a link in the article on the 1st R-4 delivery flight to the military.
https://sikorskyarchives.com/home/si...sikorsky-s-47/