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Possible uncommanded descent analysis ?

Cw4bray

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Please forgive the long crash story. A mobile device wasn't connected to the RC during this event. I used my phone for LAANC authorization but then never connected it to the controller, I felt it wasn't needed for such a short flight. I was installing a dipole antenna for HAM use, in a 55' tall tree in my backyard. The MM is much more precise at targeting a tree branch 55' distance than using a rod-reel or a slingshot, especially in a strong wind. After liftoff, I experienced a pause in climb gain at 12' until acquiring GPS. then climbed to 30' before the uncommanded descent started.
One tree connects one end of the antenna wire, the other tree connects to the other end of the wire. The feed line is in a third tree. I had been using the same sinker and fishing line on the other flights successfully. The first and second sortes went very well,
The sinker is heavy enough to penetrate foliage and pull the line up other side of the tree. The sinker is light enough to lift with the MM, I'll admit very close to max and on the edge of the performance envelope. Thanks for any input.
IMG_20200909_134145.jpg
Before anyone criticizes and says: "it's no wonder" after looking at the pictures. The only way to see this image, is to do a major inspection by removing to blades and reinstalling loctite, who does that ? Was it unairworthy ? What does the data say ? The leading edge nicks occurred after preflight inspection and during the crash sequence.

73's
 

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Inspecting props in this way is not very reliable because the baldes are viewed from slight different angles. Suggest to put the craft into hovering and check the speeds of the motors in the .DAT log file. Ideally, all motors spin at the same speed.
 
Inspecting props in this way is not very reliable because the baldes are viewed from slight different angles. Suggest to put the craft into hovering and check the speeds of the motors in the .DAT log file. Ideally, all motors spin at the same speed.
I agree with you, but a visual comparison of blade-twist at the rotor tip is very telling. RPM variations between rotors are only 50% of the equation, because each rotor has two blades that are shared. If one blade has more load and pitch than the other blade on the same rotor, the RPM could be the same yet the other blade has less lift. - Poor explanation, however there might not be a correlation between RPM and amount of lift or differential lift on the same rotor. If the washout is inconsistent at the tip where it matters most it could also be inconsistent to a greater extent at the root. I wish it was easier to see the RPM, my computer doesn't have the apps inside and on top of the other apps needed to view DAT files.
 
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