Why don't full size airplanes use bendy plastic props?

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I have been reading about both camps on the carbon fiber prop discussion.

One side says things like:
1. Don't use, gimmick.
2. Too rigid, can transmit impact energy to motors and arm that plastic props would absorb.
3. No performance gain.
4. Noisy.
5. Dont give up your EZ-prop mounts
6. Will slice your neck open.


The other side says things like:
1. Look's cool, you should deff buy these.
2. Crisper movement, better response.
3. More Durable.
4. Better battery life.
5. EZ-prop mounts suck, springs wear out.
6. Will slice your neck open.


What is the truth?

DJI offers carbon fiber props for the P3, is it just a gimmick?
If soft plastic props are the king, why don't airplanes use them?
Full size helicopters use metals and composites that are rigid but also have a degree of flexibility.

Are there any real world documented tests of a P4 using carbon fiber vs plastic?
I understand DJI engineers design these for the best optimal use....but so does my Nvidia video card, yet I can still overclock it beyond factory specs.

My point, there is always a threshold of optimal performance vs optimal life of equipment. Overclocking can provide some amazing results, but wear out the equipment faster.
Over Inflating your car tires can give you better milage, but at the expense of less traction and added wear.

Carbon fiber props arent a magical device that can suddenly increase motor output, but many folks swear by them saying that they operate more efficiently.
 
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I have been reading about both camps on the carbon fiber prop discussion.

One side says things like:
1. Don't use, gimmick.
2. Too rigid, can transmit impact energy to motors and arm that plastic props would absorb.
3. No performance gain.
4. Noisy.
5. Dont give up your EZ-prop mounts
6. Will slice your neck open.


The other side says things like:
1. Look's cool, you should deff buy these.
2. Crisper movement, better response.
3. More Durable.
4. Better battery life.
5. EZ-prop mounts suck, springs wear out.
6. Will slice your neck open.


What is the truth?

DJI offers carbon fiber props for the P3, is it just a gimmick?
If soft plastic props are the king, why don't airplanes use them?
Full size helicopters use metals and composites that are rigid but also have a degree of flexibility.

Are there any real world documented tests of a P4 using carbon fiber vs plastic?
I understand DJI engineers design these for the best optimal use....but so does my Nvidia video card, yet I can still overclock it beyond factory specs.

My point, there is always a threshold of optimal performance vs optimal life of equipment. Overclocking can provide some amazing results, but wear out the equipment faster.
Over Inflating your car tires can give you better milage, but at the expense of less traction and added wear.

Carbon fiber props arent a magical device that can suddenly increase motor output, but many folks swear by them saying that they operate more efficiently.
to answer your question I ask why don't they make full size aircraft out of cheap breakable plastic?

just kidding actually.

Been seeing the CF vs standard prop thing for years now.
My take is it is personal preference and likes/dislikes

Since I never push my phantom to its full limits
the basic standard props have worked for years now without fail
and any "maybe" gain would be unnoticeable with my usage.

Maybe a long range distance/endurance flyer would have a different thought though.

good luck and have fun flying!
 
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I would not use any props that are not DJI props. That's really the bottom line. DJI knows what the design and tolerances are of their aircraft, we do not. If you want to tinker, look at building your own custom drone where you know all of the details and what the motors and ESC can or cannot take.
 
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Carbon fiber props arent a magical device that can suddenly increase motor output, but many folks swear by them saying that they operate more efficiently.
Not exactly. CF material has different characteristics than a plastic prop, which can change things - for example the amount of amps drawn by motor/esc.
 
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I would not use any props that are not DJI props. That's really the bottom line. DJI knows what the design and tolerances are of their aircraft, we do not. If you want to tinker, look at building your own custom drone where you know all of the details and what the motors and ESC can or cannot take.

I do not want to tinker. I, and i am sure many others would just like to see real data provided by experts. I am not considering purchasing carbon fiber props.

Machines can always be pushed further than what a consumer product can do, for example....a simple antenna mod with some sail type addons is shown to increase range. This was never intended by the engineers in the final release of the product, although I am sure they were aware of the potential. Max performance is always dialed back for the consumer...for safety's sake and longevity of the product.

Does a carbon fiber prop provide any advantages?

Did this same discussion happen a year or so ago before dji introduced their own carbon fiber props for the P3?

What will be the discussion in a year when (and if) they do the same for the P4?
 
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My impression from reading various threads is that the variables of wind, battery, location, temperature, altitude, etc. tend to basically make a direct comparison virtually impossible. Over a long enough time frame and under regularly ideal conditions you might see a significant difference, but over the typical life of a Phantom it won't matter enough.

I have a set of "carbon" props for my P3P but haven't opened them yet since my existing props are still in good shape; I will probably try them next just to see what happens, but I am not expecting a noticeable difference from the stock props.

As far as airplanes using them, some already are after a fashion: the GE90 engines and their successors use carbon-composite turbofan blades.
 
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Note it's not just a matter of changing props; default factory settings might not match anymore as carbon fiber props are going to need different gains setting than plastic props.


Sent from my iPhone using PhantomPilots
 
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I do not want to tinker. I, and i am sure many others would just like to see real data provided by experts. I am not considering purchasing carbon fiber props.

Machines can always be pushed further than what a consumer product can do, for example....a simple antenna mod with some sail type addons is shown to increase range. This was never intended by the engineers in the final release of the product, although I am sure they were aware of the potential. Max performance is always dialed back for the consumer...for safety's sake and longevity of the product.

Does a carbon fiber prop provide any advantages?

Did this same discussion happen a year or so ago before dji introduced their own carbon fiber props for the P3?

What will be the discussion in a year when (and if) they do the same for the P4?
Re the antenna- two principal issues. Meeting FCC and other regulators compliance requirements and making it more likely the average user would have a chance of a connection without worrying about aiming the controller at the AC.
 

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DJI offers carbon fiber props for the P3, is it just a gimmick?
Since they don't offer any performance improvement, one explanation may be that it's the marketing department extracting more $$ from people with a thing for anything carbon
If soft plastic props are the king, why don't airplanes use them?
Over the length of the blade of a Phantom prop, the amount of flex is acceptable.
Even bigger drones use more rigid props.
In normal use the prop doesn't deflect very far.
But on a longer prop that amount of flex would be too much.
QUOTE="jakobe75, post: 1084449, member: 80992"]Full size helicopters use metals and composites that are rigid but also have a degree of flexibility.[/QUOTE]
Guessing here but if rigid rotor blades could be built, they would probably be much heavier.
Carbon fiber props aren't a magical device that can suddenly increase motor output, but many folks swear by them saying that they operate more efficiently.
And oddly those people usually can't give any actual numbers to show any improvement.
They say things like their drone is more responsive or it's crisper (whatever that means)
 

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