The flying monkeys got me...

Helis and fixed wing

AMA 957918
IRCHA 4345
AMA Intro Pilot Instructor

Saturday, April 30, 2011

ERazor Feathering Bearing Bad Karma

Got the replacement bearings for the main roto feathering shaft on the ERazor today. I found that, as I suspected, the smaller inner bearing that had shattered left the outer ring firmly stuck to the blade grip. I had to spend some 20 minutes really working it out. In this pic you can see the extracted ring next to the replacement bearing. The larger inner bearing was also bad and I ended up replacing both of them. Put the blades back on, tuned the CCPM and took the ERazor out to the garage for a test run.

Hovered great for about 4 minutes with no tracking deviation, but then one of the main blades, reused from the first crash, cracked away at the grip and I had to hit throttle hold and drop her from about a foot as she became uncontrollable. Fortunately only the blade that cracked was broken but I changed out both of them since there were some signs of damage on the other blade as well (bent the flybar back into position). This blade failed down, not up, as the upper layers of laminate came apart (I bent it down a bit more to show the crack) so I am sure it did not break in the ground strike (the heli came to rest on her skids). New blades, reset everything, and hovered her again without any issues, clean tracking. ERazor is go!

Now if I could just hover at the field...

2 comments :

  1. Ya, normally I replace blades in pairs, typically they are usually fairly close in weight when you do that.

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  2. Both of these were a matched pair, I just didn't know the one blade was badly damaged... At least I saved the darn thing!

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