Why not to trust a prop shop repair on a wood prop

When all was said and done and my drawers were replaced there was only one motor mount holding the engine on

Crap-ola!! Where did the other half go? Didn't hit the airframe? You're VERY lucky not to have had a complete engine separation.

Did the mount itself fail, bolts break, or case ears?

one of the guys on the field lost 2/3 of his prop on 185 last fall... as usual, broke all for mount legs beat daylights out of cowling... he was on takeoff on runway still luckily when it happened... a girl watched the prop blade fly by and land at the school.....

another guy in a 180 horse cub lost about a foot of a borer prop with no place to land up in mountain rock fields, backing off rpm made it shake worse, so he firewall it and it smothed out some, and he limped back to his base camp....

[h=2]Why not to trust a prop shop repair on a wood prop.[/h]What did the prop shop do? Why did it go to the prop shop in the first place? Did a lamination become unglued which then over stressed the grain?
You are fortunate that the piece didn't decide to amputate the aft section of the fuselage.

need a better/closer picture, looks like it went across different lamination layers....

why a wood prop?

Repair had been done almost 20 years ago due to a delamination close to the root as can be seen and then put on the shelf. Last year was toying with different setups pulled it down flew on it for 10 hours , one morning was @ 700' fat dumb and happy.....BAM, I was convinced that I had a mid-air with another plane. I immediately pulled the throttle , Didn't seem to help , I knew it had to be prop or engine related so I killed the mags and put it in a steep dive cause I knew the airframe wouldn't hold together with what was happening . At about tree top level the vibration finally stopped , I knew then it was prop related. All that was left to do was get it down in the only pasture makeable I had just passed.
Through the years I had read accounts of pilots losing prop weights or part of a blade...….I thought I could relate to them, But I have decided that it's kinda like a kidney stone....If you ain't never had one....You really can't !
And Tempdoug, I really wouldn't mind a laminate repair on another wood prop, Just don't think I would want it done close to the root , As you can see it just pealed off and took more blade with it as it did. would only consider it if done out close to the tip .
All bolts with stood the loads but not the mounts.
If anybody wants to see the photo's of the broke mounts let me know I'll put them up, And as some have said.....A lot of things went my way in this snafu....Funny how much praying you can get done in a short time period !

yes post pictures, we all can learn from them

Broke jury strut braket where it attaches to L.E. Spar as well as 2 bulkheads in nose area

flyrite said:

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Broke jury strut braket where it attaches to L.E. Spar as well as 2 bulkheads in nose area

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those are really important for spar strength/completing the triangles... stiffening spar...

"expect it's always about to quit, pray it don't..." or may just quitting would have been less dramatic....

Are you sure the prop failed first or did something go thru it. The reason I ask is a few years ago when I was flying my friends C90 Curtiss Jr part of the exhaust broke off and hit the prop and then got thrown thru the wing. Your right, it gets your attention and shakes the crap outa ya. Glad your ok, could have been really bad some of the places you play

Glenn

cubdriver2 said:

Are you sure the prop failed first or did something go thru it. The reason I ask is a few years ago when I was flying my friends C90 Curtiss Jr part of the exhaust broke off and hit the prop and then got thrown thru the wing. Your right, it gets your attention and shakes the crap outa ya. Glad your ok, could have been really bad some of the places you play

Glenn

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yea Glenn , No doubt it let loose where the laminate had been repaired. When I pulled it years ago you could see the area that was delaminating , It pealed from the repaired area . I remember vividly quizzing the shop guy by asking how confident he would be flying on the repair ,He said and I quote.....yes sir would fly my kids on it . BTW The shop works on certified props also.
I truly don’t have any issue with the shop though, Have used them since. I haven’t and wouldn’t bring it up after all this time and the tech that I interacted with has long since gone.
Hindsight always being 2020, I should a left it on the shelf and just used it for decoration. As I have learned many times bout flying....it’s just fun enough to kill you !

This 150 lost most of one blade a month or so ago. Supposedly the engine came clean off in the air and was found miles away. The instructor managed to put it down with minor injuries only. Some of us are suspicious that the prop had been straightened near the root from a major bend.



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It must've thrown the engine on or immediately after takeoff. Otherwise all the skill and down elevator in the world is not going to make it controllable. The engine was likely found yards away.

That's must have been one shaky ride. Are you going to have to do a complete uncover of the airframe to allow for a complete inspection?

supercub said:

That's must have been one shaky ride. Are you going to have to do a complete uncover of the airframe to allow for a complete inspection?

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No uncover, while the wings were off and repairs were being done I went through it very detailed. Due to the design of the plane, the fuselage had more damage from that vibration than the wing. And yes the ride was unbelievable

flyrite said:

No uncover, while the wings were off and repairs were being done I went through it very detailed. Due to the design of the plane, the fuselage had more damage from that vibration than the wing. And yes the ride was unbelievable

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I take it, this didn't just happen then?

supercub said:

I take it, this didn't just happen then?

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last fall, Been 100 hrs since then. These kinds of experiences either give you confidence in your mount....or show you the short comings of it. This as well as many other experiences over the last 20 years and coming up on 1800 hrs have convinced me the Monster truly has a Spirit. We have a symbiotic relationship.....It takes care of me and I take care of it !

Course I believe I might have P$$$ed it off with that little act of stupidity .