Are quieter props available for P4?

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Are there any P4 props designed primarily for lower noise operation? It's possible to make props with 3, 4, or 5 blades, like many full-size helicopters. With extra blades, more thrust/lift can be produced at the same RPM, or the blade length can be shortened, reducing the prop tip speed and therefore the noise from the tips, where most noise is generated.
 
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I've never heard of a prop solution that's quieter. It would nice though. The Q500+ from Yuneec is half the sound of a Phantom, it's really quiet, because it was designed to be quite with 13" props that spin slower, and it only does 17mph top speed. For weddings where you don't need more than 1500' range, the Q500+ is a quiet craft to use.
 
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Are there any P4 props designed primarily for lower noise operation? It's possible to make props with 3, 4, or 5 blades, like many full-size helicopters. With extra blades, more thrust/lift can be produced at the same RPM, or the blade length can be shortened, reducing the prop tip speed and therefore the noise from the tips, where most noise is generated.
HI I have seen a post here while back someone had 3prong blades,,almost look like Parrott props but not sure if dji makes these...the noise is good :)
 
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While, no doubt, you will find third party vendors peddling multi blades and other said superior performance rotors proceed with caution. You can be confident DJI has applied considerable effort to ensuring the OEM props are suited to the application providing high efficiency and unlikely to fail in use.

Multi blades and modified geometry might provide higher thrust at lower RPM (with likely reduced noise) on the test bench however the motors will require higher current from the ESC in flight. They might seem to fly ok however the propulsion system will be operation outside the design parameters with reduced efficiency and degraded performance likely and failure (particularity of the ESC) a real possibility.
 
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Hone your props! The prop is made to create lift. It needs to be rounded, blunt and smooth front side and a razor sharp back side. Take 400 grit wet sand paper and blunt the front, and sharpen the back. You want to get rid of any defects left over from the mold. If you are really **** retentive, sand off the logos and type on the blades. Fill any dings with auto glazing compound and sand smooth. Finish with 600 grit wet sand to get rid of any scratches. This will quiet props, make the drone more stable, but the sound of the motors will still be noticable. They are loud.
 
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Hone your props! The prop is made to create lift. It needs to be rounded, blunt and smooth front side and a razor sharp back side. Take 400 grit wet sand paper and blunt the front, and sharpen the back. You want to get rid of any defects left over from the mold. If you are really **** retentive, sand off the logos and type on the blades. Fill any dings with auto glazing compound and sand smooth. Finish with 600 grit wet sand to get rid of any scratches. This will quiet props, make the drone more stable, but the sound of the motors will still be noticable. They are loud.
Thanks for those tips, but the motors don't make a noticeable sound; it's the props that make the noise, especially the tips that are the part moving fastest through the air.
 
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Yeah, my Phantom has a kind of a whistling sound (my P3 did not have it). If the wind is right, I can in fact hear the Phantom from 300 meters away, almost as far as I can see it.
 
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Hot off the press discussion. I'm not sure why they would be any less quiet on a P4P as opposed to the P4P-V2. Any engineering types here care to comment?
 
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Hot off the press discussion. I'm not sure why they would be any less quiet on a P4P as opposed to the P4P-V2. Any engineering types here care to comment?
The testing might have been performed by the same engineer who determined a 6db reduction equates to 60% quieter. 6db is a quarter of the measured power and approx a 1.5 reduction in perceived loudness (67%).
 
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Are there any P4 props designed primarily for lower noise operation? It's possible to make props with 3, 4, or 5 blades, like many full-size helicopters. With extra blades, more thrust/lift can be produced at the same RPM, or the blade length can be shortened, reducing the prop tip speed and therefore the noise from the tips, where most noise is generated.
Yes they are listed on the DJI site
 

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Are there any P4 props designed primarily for lower noise operation? It's possible to make props with 3, 4, or 5 blades, like many full-size helicopters. With extra blades, more thrust/lift can be produced at the same RPM, or the blade length can be shortened, reducing the prop tip speed and therefore the noise from the tips, where most noise is generated.

Additional blades create a much less efficient "system" and are usually only used when prop clearance is an issue. The problem comes from the blade having to fly through the turbulence of the previous blade. The most efficient (yet not practical due to stability/balance issues) blade design is a single blade but 2 blades is pretty good. More blades = more turbulence and less time/space between blades. Clean air going to a blade (and any airfoil for that matter) is the goal of the design and more blades = less clean air.
 
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Also keep in mind when you add additional blades to the prop assembly you also have to increase torque/hp for the added stress/inertia etc. It's not a simple "bolt on situation" and even more so with a closed loop system controlled by a FC like our Phantoms are.

It gets kind of messy trying to figure which props help and not hurt the system.
 
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I'm not sure why they would be any less quiet on a P4P as opposed to the P4P-V2. Any engineering types here care to comment?
I read yesterday that the updated ESCs of the P4P-V2 use a sine wave for smoother changes in speed whereas the original P4P ESCs use a square wave. The smoother changes in speed help keep the average sound lower.

This guy mentions more detail about it in his review video starting at about 2:43.


A giant disclaimer is that this is not an area of expertise for me. I am only repeating what I heard and don't know for sure if it's accurate or even makes any sense.
 
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Are there any P4 props designed primarily for lower noise operation? It's possible to make props with 3, 4, or 5 blades, like many full-size helicopters. With extra blades, more thrust/lift can be produced at the same RPM, or the blade length can be shortened, reducing the prop tip speed and therefore the noise from the tips, where most noise is generated.
The new P4P v2 h supposedly is quieter. They have new motors with a new design to the blades. They are shorter and wider. So there is less leading and trailing edge. They are claiming it is 4db quieter. So perhaps you could order those new bladed.
 
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I wonder if the props from the new P4P V2 will work on the P4P...... anyone know?
 

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