Also, FWIW. I've always hand tightened mine and have never had a problem. But, then my props have only been taken off I'm guessing 15 to 20 times. Just me, but I trust my fingers to know how much force is enough. I'm worried that if I used a tool I would apply too much force.
P3P Falls Out of Sky within a few seconds...WHY?
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Another option would be to wind PTFE (plumbing) tape round the threads of the motors before fixing the props. The direction of the winding is according to whether the prop is CW or CCW. It's thus a sort of 'sacrificial' thread, instead of ripping up the composite threads on the props if you progressively overtighten them over time. It can be renewed as and when needed. I use this method to fly P2 metal-hubbed props on my P3P.
I never have. They should tighten themselves.
Strange the bird is sitting there nicely for a while before it happens. You would think it would have happened sooner if it was loose.
Yep, you lost a prop for sure unfortunately. Commiserations.
I spin the props on and once stopped, I then hand-tighten them further about a 1/6th turn more and that means they're properly tight. Never had a problem getting them off by hand and there is zero wear on the hubs.
I spin the props on and once stopped, I then hand-tighten them further about a 1/6th turn more and that means they're properly tight. Never had a problem getting them off by hand and there is zero wear on the hubs.
Over tightening could cause a problem like this as well. I actually think it would be more likely the cause.
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I believe that if you're not eye-balling it well, you can use your fingers to hand tighten it and feel it tighten, but it could still not be on properly.
Here's what I've observed: put the prop on, spin the proper direction, then watch for the spin.
Chris
Here's what I've observed: put the prop on, spin the proper direction, then watch for the spin.
- If it freely spins several times before hitting the fully-threaded tight spot, you're good to hand tighten it and be confident it's on proper.
- If it doesn't spin very much, becoming tight right away (less than 1 revolution), it didn't thread proper. You can reach down and cinch it tight with your fingers and it will feel tightened, but it's still not on correctly.
Chris
How so?
1/ I really think you'd have a hard time "overtightening" the props and
2/ if you did manage it, the threads would strip and you'd know that for sure.
Did you examine the prop that came off? The threads? I overtightened or had a defective prop on my P3P. It continued to turn while tightening. It never reaching "tight" like the others. I immediately replaced it. But if you had a crack in the flange of the prop, bad threads, stripped threads, etc., then the motor action to tighten it may have taken it past the point to failure. I think you said this was your first flight on it and it was previously owned. Perhaps it was a problem waiting to happen. One thing for sure, it came off. If you have the prop, it would be easy to see why. Just try putting it back on. If the motor still functions normally and the hub looks OK, it had to be in the threads of the prop, not tight or stripped.
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You shouldn't just "spin" the props on like i've seen some people do. The motors are continuously changing speed. The props can back off with these speed changes. Make sure to tighten by hand before you take off. The tool is to help you remove the props should they be too tight.
I now have 10 different drones, big part of my interest besides flying them is recovering and fixing drones. One thing is constant. Props spinning of. As a matter of practice now I tighten down the props before each flight day and especially after a bad landing.
This discussion troubles me. I have always hand tightened meaning spining them on and then give them a little more. I had no idea these "self tightening" props could spin off.
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I find two things of interest. Scrubbing back from the frame showing the "prop" flying off I found a couple more frames with this object further away to the right. That along with the direct of flip and the fact that the "Motor Idling (Loose or Missing Propeller)" messages don't start until AFTER the craft has hit the ground! I think this was a (very fast) bird strike coming in from the right, which caused a tumble to the left, sending the bird (or whatever object it was) shooting up. This caused the crash, the broken propeller, and the subsequent error messages.
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If that is a prop, it is a very big prop.
And it appears his props are the standard DJI white, not dark like the object above.
If I missed something here, please let me know. I would like to get this figured out correctly.
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And it appears his props are the standard DJI white, not dark like the object above.
If I missed something here, please let me know. I would like to get this figured out correctly.
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There is a good reason why many birds, particularity predatory sea birds have white plumage on the underside. Regardless of what colour an object is it will appear dark in silhouette in front of a bright object. On the availabke information prop loss, while not a certainty, is the most likely scenario in this case. The missing prop was found intact, if it struck a bird or other object it may have broken but it would not come undone (the impact would tighten it).
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Still does not explain the log. In 6/10 of a second the aircraft went from stable flight to lawn care. On after hitting the ground did the error messages start. I'm not saying it did not throw a prop, just that some of these things don't add up. If it was the right front prop that came off the torc should have flipped the bird to the right but the video shows it flipping to the left. I'm no expert, and I don't play one on tv, I just want to know what happened so I can keep my P3P from doing something similar.
The datcon analysis clearly depicts the motor speed increase that is typical of the many discussed prop loss cases, and the prop was found away from the AC in perfect condition.
What a shame not a good first flight. Just out of curiosity you mentioned this is your second refurbished P3, what happened to the first one?
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