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Sikorsky S-92. Book 2, “Polyphia”

Butch W.United StatesSep 7, 2024 Share
Chapter 22 of 40

Back in the Saddle.

Aug 20, 2025

UIH,

All righty then, I had to step away from my projects for several weeks and finally getting back to some projects.

After the last flights the first week in July, I noticed some wear on the main gear. On that flight during approach to landing, the heli required more collective than usual. It appears something shifted to the tune of about 1 mm in the main shaft causing this wear. Upon disassembly the shim stack had a gap of .75 mm that compromised the gear mesh causing the abnormal wear. After looking everything over and checking that all locking collars remained secure, about the only thing I could come up with is the center bearing block bearing may not have been seated all the way and shifted during flight. I removed all the bearing blocks to double check all bearings were seated properly then re-assembled adding a .75 mm shim in the stack. I installed a new main gear and the drive train is moving as smooth as silk.

While down it was time for some upgrades. I replaced the swash plate and driver, installing a brand new head and changed the one way gear from 70t to a 65t. After many data flights, the power out was a touch high for my taste. I use the Castle 160. With the Nr I am running, it gives the warning 'too fast for proper governing'. I know its a scale machine and the 160 is very conservative on its calculations but the slight change will be a good thing overall.

Still have some things to finalize before flight but hopefully will get back to the field in a week or two

A foot note. I received the molds for the glazing from Evan a few days ago. They look great. I have a place local that can vacuum the glazing so I can get moving on the cockpit. I also dropped in a couple photos of the servo install. These MKS 575 low profile servos have been great. Powerful and fast.

A few pics.

Thanks for dropping buy,

B

Chapter 22: Back in the Saddle.
Chapter 22: Back in the Saddle.Chapter 22: Back in the Saddle.Chapter 22: Back in the Saddle.Chapter 22: Back in the Saddle.