What puts chips on the face of a propeller?

Discussion in 'Maintenance Bay' started by arnoha, Aug 13, 2020.

  1. Dan Thomas

    Dan Thomas Final Approach

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    And without a proper stripping and NDI you'll never find that crack that could kill you. The prop manufacurers have overhaul period specs for a reason.

    The prop is the most highly stressed part on the entire airplane. Centrifugal forces are enormous. It's why there are overspeed limits and inspections specified for incidents outside the limits. 10% over redline for a few seconds is a typical limit. It produces 21% more force on the prop. Contrast that with airframe loads of 280% over normal as a limit.
     
  2. Tom-D

    Tom-D Taxi to Parking

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    There are way to find cracks without overhauling.
    Stripping, cleaning and re-finishing is called a repair.
     
  3. Tom-D

    Tom-D Taxi to Parking

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    There ya go again.
     
  4. arnoha

    arnoha Cleared for Takeoff

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    Even at overhaul, the prop only gets shortened if there's a reason for it. No reasonable prop shop is going to take more off a prop than is needed to bring it back into spec.

    In exchange for an extra $300, I get a pretty prop back to acceptable factory spec and a break on insurance. Seems a good trade to me.
     
  5. Tom-D

    Tom-D Taxi to Parking

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    when the prop is overhauled it gets a lot of service life ground away.
     
  6. idahoflier

    idahoflier Line Up and Wait PoA Supporter

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    I know time is $ but just thought I would mention these folks stripped, dressed, balanced and re-painted my prop for $371. I was quoted $800 to overhaul... No idea what it costs to ship a prop, but I imagine significantly less than $1K...

    https://www.precisionpropellerservice.com/
     
  7. arnoha

    arnoha Cleared for Takeoff

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    Thanks for the link! Hopefully won't need it again for a while, but good to have in my pocket. Aargh...reminds me...I should do a dynamic balance of the prop once it's bolted back on. The prop had to be shipped anyway...the shop that's doing the work is in Redding, CA and my plane is in Palo Alto, CA.
     
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  8. RhinoDrvr

    RhinoDrvr Pre-takeoff checklist

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    I’m confused. Assuming this was a 4-cyl airplane, what’s the problem? 8.0 GPH fuel burn at cruise (sometimes lower), 1.0 gal taxiing to the pump / accuracy of the fuel gauge / how far up the filler neck do you go...where I’m going with this is, he could have had his required 30 minute reserve onboard at touchdown.

    On a severe clear VFR day I’ll fly down to 4 gallons in my RV no problem. IFR, or potentially cross country where I am carrying an alternate is a different story of course.
     
  9. Dan Thomas

    Dan Thomas Final Approach

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    How the the three gallons was measured is what's at stake here. A calibrated dipstick used when the airplane is on a level surface is the best way, but the person making and calibrating that stick must take into account the unusable fuel as per TCDS. That's the fuel that won't flow out of the tank in certain attitudes such as a Vx climb. If the dipstick is wrongly calibrated with its zero at totally empty tank it's asking for trouble. Zero is supposed to be at the unusable fuel level.

    I know of a 150 whose engine quit on final due to that. A 150 has big flaps and a steep nose-down attitude in a power-off glide and there is significant fuel that can't get out via the outlet which is a bit aft of the inboard center of the tank. That 150 had a stick calibrated from an empty tank and they didn't have the fuel they thought they had. The PIC was a smart instructor and he raised the flaps to 20° to flatten the glide, the aircraft's attitude flattened out some, and the engine came back to life long enough to reach the runway.
     
  10. donjohnston

    donjohnston Cleared for Takeoff

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    Bad assumption.

    The Cessna 182-RG has a Lycoming O540. In cruise I figured 13GPH.
     
  11. RhinoDrvr

    RhinoDrvr Pre-takeoff checklist

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    Definitely a problem then! Yikes!
     
  12. AeroLudite

    AeroLudite Pre-Flight

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    My vote is a chock rope and chock. The brush marks by wood abrasions and gouged by a screw eye. Saw it happen once when a/c taxied across a randomly placed chock.
     
  13. arnoha

    arnoha Cleared for Takeoff

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    Just to finish this one out...prop was overhauled by American Propeller and now it's pretty again. Including R&R, shipping, inspection, overhaul, and everything, it was just under $2000.
     
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  14. idahoflier

    idahoflier Line Up and Wait PoA Supporter

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