3 blade carbon fiber disaster never again!!

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I thought it would be fun to goof around with 3 bladed props carbon fiber.Ordered them from China they came today.As soon as i hit the throttle the two front props appeared to have more pitch and it just flipped over and crashed.making this horrible sound like gears stripping out.Should i be concerned about this sound i heard?Any help would be great and yes i have learned my lesson...yes i'm stupid but they do look cool or did lol
IMG_3006.jpg
 
Rotate the motors by hand. You should feel a very slight catch but that is it. Check the motors for debris - that happens a lot. Blow out gently with air. Once you have done that, take the props off and start the drone. Everything should rotate without undo noise or smoke or smell.

You're probably OK, but you need to check it carefully.
 
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Rotate the motors by hand. You should feel a very slight catch but that is it. Check the motors for debris - that happens a lot. Blow out gently with air. Once you have done that, take the props off and start the drone. Everything should rotate without undo noise or smoke or smell.

You're probably OK, but you need to check it carefully.
Thanks Man.
 
i've got the nylon 3-blades on order
 
The DJI propulsion engineers already have done the hard work to calculate the best props for the motors for your P3.
Popping on some random props because they look badass isn't going to improve the performance at all.
If it was that simple, DJI would have done it already.
 
There a sooo many threads here which have similar outcomes as the OP experienced yet folks continue to make the same mistakes.
Phantoms are a closed Eco system camera platform and are optimized for such.
 
Sorry about the OP's troubles but . . .

I'm boggled how many people buy these "gimmick" items without realizing the bigger picture. A 3-blade(or more) prop is designed for high performance and high horsepower applications. Unless you're designing a stunt plane or have some extreme prop-clearance problems you're only hurting yourself going with more blades. Part of the problem is the fact that the additional blade cause exponentially more turbulence putting the following blade into crappy air. Ideally you'd have fewer blades to give the next blade the best opportunity to get some fresh CLEAN air to use to create lift/propulsion with. The most efficient blade design is a single blade but that introduces a whole new set of problems into the equation.

As noted above this is a "Finely Tuned System" and the engineers have tweaked it about as much as possible. Remember you're working with more than just mechanical systems here and the aircraft is controlled by software designed to maintain a specific operating environment. It's entirely possible changing one aspect of the "system" can cause new variables introduced that the "system" will try to offset to get things back to "expected" parameters. This is just like adding a new exhaust/intake system to a computer controlled car. Even though it's "better" for the system the computer is expecting very specific parameters and it will detune the car to meet those parameters or go into LIMP mode as it things there is a fault. In this instance you'd have to "program" the chip in the car to allow for the new (improved) parameters.

In regards to the "flipping over" I suspect it's a defective blade or a blade(s) in the wrong position. Just a wild bass guess though.
 
Sorry about the OP's troubles but . . .

I'm boggled how many people buy these "gimmick" items without realizing the bigger picture. A 3-blade(or more) prop is designed for high performance and high horsepower applications. Unless you're designing a stunt plane or have some extreme prop-clearance problems you're only hurting yourself going with more blades. Part of the problem is the fact that the additional blade cause exponentially more turbulence putting the following blade into crappy air. Ideally you'd have fewer blades to give the next blade the best opportunity to get some fresh CLEAN air to use to create lift/propulsion with. The most efficient blade design is a single blade but that introduces a whole new set of problems into the equation.

As noted above this is a "Finely Tuned System" and the engineers have tweaked it about as much as possible. Remember you're working with more than just mechanical systems here and the aircraft is controlled by software designed to maintain a specific operating environment. It's entirely possible changing one aspect of the "system" can cause new variables introduced that the "system" will try to offset to get things back to "expected" parameters. This is just like adding a new exhaust/intake system to a computer controlled car. Even though it's "better" for the system the computer is expecting very specific parameters and it will detune the car to meet those parameters or go into LIMP mode as it things there is a fault. In this instance you'd have to "program" the chip in the car to allow for the new (improved) parameters.

In regards to the "flipping over" I suspect it's a defective blade or a blade(s) in the wrong position. Just a wild bass guess though.
I'm sure defective blades you can't put the blades on wrong two are silver two are black tipped.
 
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I have considered alternate props too. As an Air Race fan, I've always been interested in these sorts of things.

I read an interesting article a while back about a single bladed prop that was used on light aircraft with a counterweight on the other end. This was actually more efficient than a 2-bladed prop for that very low horsepower plane.

In order to use available horsepower and not exceed clearance limits though, more blades are usually needed.

Here's a couple of my air race shots featuring blades and more blades. The first is a stock Hawker Sea Fury with a Rotol 5-blade prop. The second and third are of "Precious Metal" highly modified P-51 with a larger than stock RR Griffon engine and two counter-rotating 3-blade props that were used on an airliner and some prototype late-war Spitfires. PM is the only survivor of three race Mustangs that have been modified similarly in the past. PB was damaged heavily by an engine fire on the ground before last year's race and will be out for a while. Anyway, thought you might like this in the prop discussion:
15b1d7b4af809707b5d43c93a92b5247.jpg

1e0f5030951247f3e8956cea997cb00c.jpg
c909989c8248676bb93c730861122745.jpg



Sent from my iPhone using PhantomPilots mobile app
 
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Sorry for the shots not showing up in the order I intended. Also "PB" is supposed to be "PM" for "Precious Metal"


Sent from my iPhone using PhantomPilots mobile app
 
more is not always better. the propulsion system is designed on thrust vectors and torque... all built around motor speed. when you change the input variable the drone has no idea that the props are different. So when the drone tries to fly it applies power in a way that does not match factory props so god only knows what the flight computer does to compensate.
 
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I have considered alternate props too. As an Air Race fan, I've always been interested in these sorts of things.

I read an interesting article a while back about a single bladed prop that was used on light aircraft with a counterweight on the other end. This was actually more efficient than a 2-bladed prop for that very low horsepower plane.

In order to use available horsepower and not exceed clearance limits though, more blades are usually needed.

Sent from my iPhone using PhantomPilots mobile app
I heard the same thing about single blade props from Prof Applegate back in college.
Single-blade propeller - Wikipedia, the free encyclopedia
 

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