Nice explanation! One aspect of prop theory that seems to get left out is that the curved nature of a prop reflects the fact that different parts of the prop have different pitches - starting with the tip of the prop having the least pitch and the part closest to the hub having the greatest pitch. The pitch given for a prop is really an ‘average pitch’. This is because the different parts of the prop are all travelling at different speeds. The tip (having the greatest circumference) travels at a faster speed in its rotation than the part closest to the hub which has the least circumference and which travels at the slower speed in its rotation. The prop has to be designed so that all parts of the prop are are trying to get to the same place at the same time - hence the low pitch at the tip and the much higher pitch near the hub.
Hi, nice and clear demonstration ! Another quick and precise rule of thumb is that one : D2 = D1 x (Nblade1/Nblade2)^0,25. This leads to 2 factors @ iso-pitch : - From 2 blades to 3 blades, multiply the diameter by 0,9 - From 2 blades to 4 blades, multiply the diameter by 0,84. That's an easy precise one ;o)
Just come across your channel thanks very much indeed you have very simply explained how to convert from a 2 blade to 3 or 4 blade propeller I hate it when I see a 2 blade prop on a scale model when I know it should be either a 3 or 4 blade prop
Wow! That was informative. I was trying to reduce propeller size of my pusher design to help reduce overall size of plane. This equation helps a lot for that. Thanks for sharing.
oooh Thanks a lot ... this is what i can call a tuto or an answer to how .. all other videos about props in others chanlers are stupid this is what we call it Engeneering ... thank you again
Thank you, simple and clear. Excellent. Btw, in my case, to spare someone 3 mins of maths :) For prop 19x8, from 2 to 3 blade, d on 3 is 4913, so d=aprox 17. From 2b 19x8 need 3b 17x8. Cheers
Load factor on 2b is 6859. Divide that by sqrt2 gives 4851. Get the cubed root of that you get 16.9. so yes, 17 inch diam. (Keeping the same pitch for both)
You may want to ignore the final rule of thumb if you play with bigger props, as I do. The conversion load of my 27x10 electric 2-blade is actually a 24x10x3. I suggest doing the math for all sizes. If you can use Excel, it's very easy using the formulas represented here. I'm also curious to know if when you ran the 9x6x2 and the 8x6x3 in a static test on the same motor with the same battery, if the current readings were the same? That would be extremely valuable information. Of course, using something like a Rapala digital scale to measure the static pull from each prop on the same motor would also be extremely valuable data.
Good morning so I have a question for you. I have an FYP 51 1.5 that comes with a four blade propeller. I am trying to put a two blade propeller and I am unsure of the size that I want to use so that this will run properly maybe you can help.
Hello, this is a good video for lots of guys! Two small comments though: (1) your method assumes that both 2 and 3-bladed props must generate the same thrust in the end. (2) the dependency of the prop thrust on pitch is less than the power of one. From experimental data published in RC Groups, thrust changes with D^3.5 * P^0.5 as opposed to D^3 * P.
Hi, you make good points, and there is a huge amount of debate on the forums on the topic of PLF. Most RC pilots change diameter or pitch choice depending on how they want the plane to perform, so even after these calcs are done there is still room for manoeuvre. The debate continues...!
Hi, there's A LOT on rcgroups.com on this subject and the two methods I've presented here are the best approximations from my research on this. It will get you very close, particularly the first (longer) method, and you can play with pitch etc. to get the best performance for how you like to fly the model.
Can you tell how to make my own custom propeller like selection of airfoil, twist, diameter for given requirement of thrust. Can you please suggest any book or online tutorial for this. I am trying in Qblade. It would be a great help from you!!
Conor, I have used different equations than this an I do like the simplicity of your method. I have researched this too from the perspective of power consumption... in other words how can I change the prop (blades, diameter) and not change the power required to turn it. D1x(b2)^0.25 = D2x(b1)^0.25 where D1 & D2 are diameters of the props and b1 & b2 are the respective number of propeller blades. When I compare it to your calculator method it provides very similar results.
Thank you so much for the explanation... but I need some help in my case a have recommend propeller 1045, and I want a propeller with 6blades and when I do the equation 10x10x10=1000 and I have 2,23 as ratio of 5 and I have 448, when I approximate I found 7.6 approx so it's still a big number of propeller if a think about it I don't know if I'm doing it well... thank so much if you can help me
Hi, I've just done the calculation. From what you say I believe you have a 5-blade 10x4.5 prop and want to use a 6-blade prop. By my calcs the load works out at 9000, giving a diameter of 9.6 inches. Same pitch of 4.5. If you go down to a 9 inch blade the pitch will need to be 5.5 to keep the loading equal. Hope this helps.
Thank you so much, but actually 1045 recommend propeller it's a 2 blade and I want to use a 6 blade probably this can could be more understandable, so i don't know ... thank you so much
Hi, more blades offer a little more ground clearance which I wanted for the model I'm building (a Slow Poke). It's a tail-dragger so the nose will tip towards the ground on take-off. Also, for the style of the model I felt that 3 blades would look nicer. In general a 2-blade is more efficient but 3-blades can be a little quieter. For a more in-depth look at the pros and cons see this site: hartzellprop.com/are-more-propeller-blades-better/
I'm curious about the math behind the D³*P*√N-1 formula. I looked through some of my resources on airfoil design, but couldn't find this one. Where does it come from? What's the logic behind it? Would love to know. Thanks!
Alternatively read the packet that Master Airscrew (what you used in the video) 3-blade props come in - 2-Blade to 3-Blade conversion: Decrease diameter by 1" and increase pitch by 1". Adjust to 2" for larger diameters (14" and up) 😆 (At least you didn't disagree with each other, haha 😅)
How would this apply to changing as ex. 42 mm 2 blade prop to a 3 blade prop? Changing a 9 inch 2 blade to a 8 inch 3 blade is a certain ratio proportion...so could you do an equation of 228 mm (9 inch) is to 203 mm (8 inch) as 42 mm is to x mm ? And that would be 35.6 mm (all approx.)
Hi, it's not possible to perform a direct ratio calculation due to the effect of the cubed root. But the maths are unit independent, so using the same equations will give you the correct diameter anyway.
Some planes need smaller diameter propellers for ground clearance, to avoid any chance of the blades clipping the ground. True that more blades weight more, but the propeller diameter is reduced, so it compensates.
I think it has to be taken into account that increasing the number of blades reduces the efficiency because they are in each other's swirl. The efficiency of a single blade propeller is the highest. However, it is very rare to come across a blade propeller because it is difficult to balance and only one blade gets all the load.
Hi, these pilots may have done this as the lower pitch will produce more pulling power from standstill, but sacrifice top speed. Pilots can choose from a range of propellers to suit their powerplant. The video shows how to do a straight conversion from 2 to 3 blades (and vice versa) but some pilots may choose higher or lower pitches to change the model's flying characteristics.
ESC controllers and CPU are designed for 2 blade props , sure you can change it to 3 or 4 prop designs , however now the motor will not spin at the same RPMs and could make the motors run hotter or out of spec input readings making the ESC or CPU errors . I am not risking a $3,500 drone to try a different prop .
I didn't think this video had anything to do with RC Cameras. I thought this video was for people who's RC Airplanes always come with 2 blade props, but the Life-Sized, Real-World counterparts always have 3 blade Hartzell Props. They want to convert for realistic, scale looks, but retain flight capability and efficiency. Most of these type of people are definitely doing this mod or they wouldn't even want the plane anymore, lol.
excellent to see this...i left the forums years ago because of way too much 'trial and error' and pseudo science. The latest generation of ducted fans has only just realised that for RC, thrust is king..and now stuff their fans with blades. The vasafans of yesteryear, and some of the wemotecs are faster, and still work if you get the ESC, V, motor right.
Many thanks for this Conor ... great to know the conversion as I prefer 3 blade props ... I assume this conversion equation works in a similar way from 2 to 4 blade but would be DxDXDXDxP / quad root of N-2
Hi, the only thing you need to change is N, the number of blades. The formula would be D x D x D x P x SQRT(4-1). In my example, a 2 blade 9x6 would equate to a 4 blade 7.5x6.
Or you could just simplify it and say if you take your original prop cut it in half take that measurement of half of it and that's what each prop should be on your new three prop blade.....sorry if i didn't word that very well
Interesting but I usually want to keep the prop size the same and change the pitch so the model keeps a good look with the size of the prop. That'll take a little more math I guess.
You can use the same equation, just keep the diameter the same. I get the feeling it'll require a big change to the pitch value to balance the equation.
It will keep going up until the batteries run out! Keeping it under control, which you should do at all times, is down to the range of your radio equipment.
AT 416 THE "music" CAME ON AND I COULD HERE NOTHING YOUR WERE SAYING! WASTE OF MY TIME! OW! IT NOW STOPPED! GOD EXISTS! very good video! "EDUCATIONAL!"
@@jch8175 its "NOT!" an "entertaining!" video! its an educational one! one that educates the person watching it and not wasting your time by entertaining you like at "VEGAS!" were we all sing and dance to the drug music/medication music! he clearly is not involved with "NATIONAL GEOGRAPHIC!" were you are completely "entertained" with "beautiful" pictures of the world while playing "RELAXING!" drug music while somebody describes what is happening to you while you are all "messed-up!" from the "relaxing" music! its also difficult to here what a person is saying and its very annoying for no "APPARENT!" reason! this is just a very brief answer to your question! EVER BEEN TO COLLEGE! NOBODY "LECTURES" WITH MUSIC GOING! the word "lecture" means you have to "THINK" with something called "THOUGHTS" about what the person is saying and understand them! with national geographic your simply told the plant is "GREEN!" their are no thoughts! their is no thinking! but they are a very prestigious! organization! for "WHAT THEY DO!" they entertain you!
Not quite what i wanted to know. But hearing such a gebtle irish voice explain something technical... HOW CAN I NOT WATCH... im a man :'( Why the music though :s
That will depend on the available power. There's a good discussion here on the factors that affect large vs small propellers. www.rcgroups.com/forums/showthread.php?28219-Big-prop-low-rpm-or-small-prop-high-rpm
If that is Chinese 2212 1000kv. Most efficient is 9x4.7. 2 blade carbon prop. And 3 blade is 8x4 ... The best results tested the drag. Rpm Vs thrust output. In practice.. I tested it on 2212 1000kv. 9x6 prop is a bit to big pitch. For 1000kv on 3s. 9x4.7 is spot on efficient for 2 blade and 3 blade I would confidently put 8x4 produced best current draw Vs rpm and thrust output of 1.1kg
I'm more a visual and images right side of the brain kind of guy. Mathematics and logic is for the left side of the brain and no my specialty. To my best understanding... Do using 3 blades insted of two increses the lift for a drone while decresasing battery consuming and improving battery time? The pith of the blade is more pronounced at the center than at the tips. Why is that? Thanks for your explanation on this area.
For the second part of your question you should read Alex Gouthro's comment which describes very well why propellers are shaped like they are. In your first question you have to think about the load the propeller puts on the motor. You can gain small efficiencies by changing pitch or number of blades but the motor may struggle. Adding an extra blade should make the propeller quieter for the same performance, producing 3 smaller pressure pulses rather than 2 bigger ones.
That confirms what i was always told, drop an inch in diameter or drop one in pitch. Has always worked for me, no math required.
4:00 Music all of a sudden?!
Nice explanation! One aspect of prop theory that seems to get left out is that the curved nature of a prop reflects the fact that different parts of the prop have different pitches - starting with the tip of the prop having the least pitch and the part closest to the hub having the greatest pitch. The pitch given for a prop is really an ‘average pitch’.
This is because the different parts of the prop are all travelling at different speeds. The tip (having the greatest circumference) travels at a faster speed in its rotation than the part closest to the hub which has the least circumference and which travels at the slower speed in its rotation. The prop has to be designed so that all parts of the prop are are trying to get to the same place at the same time - hence the low pitch at the tip and the much higher pitch near the hub.
Hi, nice and clear demonstration !
Another quick and precise rule of thumb is that one : D2 = D1 x (Nblade1/Nblade2)^0,25.
This leads to 2 factors @ iso-pitch :
- From 2 blades to 3 blades, multiply the diameter by 0,9
- From 2 blades to 4 blades, multiply the diameter by 0,84.
That's an easy precise one ;o)
Excellent video. Very informative and detailed with no running off on irrelevant topics.
Just come across your channel thanks very much indeed you have very simply explained how to convert from a 2 blade to 3 or 4 blade propeller I hate it when I see a 2 blade prop on a scale model when I know it should be either a 3 or 4 blade prop
Thank you for the great explanation. Planning of changing to 3 blades of my hubsan.
Thank you! Nice video but I don't understand why the music in the middle of the vid hahah
Wow! That was informative. I was trying to reduce propeller size of my pusher design to help reduce overall size of plane. This equation helps a lot for that. Thanks for sharing.
Well, I've learned something new today. Thanks.
Thanks mate, i was looking for this for a week :)
oooh Thanks a lot ... this is what i can call a tuto or an answer to how ..
all other videos about props in others chanlers are stupid
this is what we call it Engeneering ... thank you again
thank you , i can now convert my 2 blades to 3 blades ,very good video
Excellent, thanks for the calculation!
That's the hardest work to learn 9 minus 1 👍😂🤣
Thank you, simple and clear. Excellent.
Btw, in my case, to spare someone 3 mins of maths :) For prop 19x8, from 2 to 3 blade, d on 3 is 4913, so d=aprox 17. From 2b 19x8 need 3b 17x8. Cheers
Load factor on 2b is 6859. Divide that by sqrt2 gives 4851. Get the cubed root of that you get 16.9. so yes, 17 inch diam. (Keeping the same pitch for both)
Cool! Learned something new
You may want to ignore the final rule of thumb if you play with bigger props, as I do. The conversion load of my 27x10 electric 2-blade is actually a 24x10x3. I suggest doing the math for all sizes. If you can use Excel, it's very easy using the formulas represented here. I'm also curious to know if when you ran the 9x6x2 and the 8x6x3 in a static test on the same motor with the same battery, if the current readings were the same? That would be extremely valuable information. Of course, using something like a Rapala digital scale to measure the static pull from each prop on the same motor would also be extremely valuable data.
Thanks for the explanation.
Ive always heard in general if you add a blade you drop an inch and decreasep pitch slightly too would you recommend decreasing pitch .
You would have to play with the numbers to get both sides to match. In some cases this could mean using a different pitch to get equality.
That’s very clever. I know know what the sizes mean as well. I guess their must be a calculation for pitch verses power.
Good morning so I have a question for you. I have an FYP 51 1.5 that comes with a four blade propeller. I am trying to put a two blade propeller and I am unsure of the size that I want to use so that this will run properly maybe you can help.
Hello, this is a good video for lots of guys! Two small comments though: (1) your method assumes that both 2 and 3-bladed props must generate the same thrust in the end. (2) the dependency of the prop thrust on pitch is less than the power of one. From experimental data published in RC Groups, thrust changes with D^3.5 * P^0.5 as opposed to D^3 * P.
Hi, you make good points, and there is a huge amount of debate on the forums on the topic of PLF. Most RC pilots change diameter or pitch choice depending on how they want the plane to perform, so even after these calcs are done there is still room for manoeuvre. The debate continues...!
My motor is 2212 1400kv,,,plase suggest a 3 blade prop for 1400 kv motro on 2s lipo
Nice ! and now you can make a video to explain your formula and show why we raise the diameter to the power of 3 in both cases
Thank you for the video. Can you tell me where you got the equation from?
Hi, there's A LOT on rcgroups.com on this subject and the two methods I've presented here are the best approximations from my research on this. It will get you very close, particularly the first (longer) method, and you can play with pitch etc. to get the best performance for how you like to fly the model.
Can you tell how to make my own custom propeller like selection of airfoil, twist, diameter for given requirement of thrust. Can you please suggest any book or online tutorial for this. I am trying in Qblade. It would be a great help from you!!
Conor, I have used different equations than this an I do like the simplicity of your method. I have researched this too from the perspective of power consumption... in other words how can I change the prop (blades, diameter) and not change the power required to turn it. D1x(b2)^0.25 = D2x(b1)^0.25 where D1 & D2 are diameters of the props and b1 & b2 are the respective number of propeller blades. When I compare it to your calculator method it provides very similar results.
That's good work, thanks. I'm glad my shorthand method gets such similar results.
Very nice video
Thank you so much for the explanation... but I need some help in my case a have recommend propeller 1045, and I want a propeller with 6blades and when I do the equation 10x10x10=1000 and I have 2,23 as ratio of 5 and I have 448, when I approximate I found 7.6 approx so it's still a big number of propeller if a think about it I don't know if I'm doing it well... thank so much if you can help me
Hi, I've just done the calculation. From what you say I believe you have a 5-blade 10x4.5 prop and want to use a 6-blade prop. By my calcs the load works out at 9000, giving a diameter of 9.6 inches. Same pitch of 4.5. If you go down to a 9 inch blade the pitch will need to be 5.5 to keep the loading equal. Hope this helps.
Thank you so much, but actually 1045 recommend propeller it's a 2 blade and I want to use a 6 blade probably this can could be more understandable, so i don't know ... thank you so much
Can you explain what the advantages and disadvantages are of adding blades? Is the advantage simply smaller diameter?
Hi, more blades offer a little more ground clearance which I wanted for the model I'm building (a Slow Poke). It's a tail-dragger so the nose will tip towards the ground on take-off. Also, for the style of the model I felt that 3 blades would look nicer. In general a 2-blade is more efficient but 3-blades can be a little quieter. For a more in-depth look at the pros and cons see this site: hartzellprop.com/are-more-propeller-blades-better/
I decrease one inch of D and one of P.
Same P on 3 blades usually means upper temperatures and less flight time
I'm curious about the math behind the D³*P*√N-1 formula. I looked through some of my resources on airfoil design, but couldn't find this one. Where does it come from? What's the logic behind it? Would love to know. Thanks!
Hi, it's propeller load factor. The principle is to keep the load factor the same whilst changing the number of blades.
Alternatively read the packet that Master Airscrew (what you used in the video) 3-blade props come in - 2-Blade to 3-Blade conversion: Decrease diameter by 1" and increase pitch by 1". Adjust to 2" for larger diameters (14" and up) 😆 (At least you didn't disagree with each other, haha 😅)
How would this apply to changing as ex. 42 mm 2 blade prop to a 3 blade prop? Changing a 9 inch 2 blade to a 8 inch 3 blade is a certain ratio proportion...so could you do an equation of 228 mm (9 inch) is to 203 mm (8 inch) as 42 mm is to x mm ? And that would be 35.6 mm (all approx.)
Hi, it's not possible to perform a direct ratio calculation due to the effect of the cubed root. But the maths are unit independent, so using the same equations will give you the correct diameter anyway.
why would u want to switch number of propellers though? And wont more blades weigh more?
Some planes need smaller diameter propellers for ground clearance, to avoid any chance of the blades clipping the ground. True that more blades weight more, but the propeller diameter is reduced, so it compensates.
Can you teach me how to calculate the thrust? Given with Pitch, Speed(rpm), diameter.
Hi, give this a go and see if it helps : rcplanes.online/calc_thrust.htm
I think it has to be taken into account that increasing the number of blades reduces the efficiency because they are in each other's swirl. The efficiency of a single blade propeller is the highest. However, it is very rare to come across a blade propeller because it is difficult to balance and only one blade gets all the load.
If that is the case, how did rc sailors use a 12 X 5 - 2 blade on the fms T28 Trojan 1400mm model that comes stock with a 12 X 7 - 3 blade prop?
Hi, these pilots may have done this as the lower pitch will produce more pulling power from standstill, but sacrifice top speed. Pilots can choose from a range of propellers to suit their powerplant. The video shows how to do a straight conversion from 2 to 3 blades (and vice versa) but some pilots may choose higher or lower pitches to change the model's flying characteristics.
ESC controllers and CPU are designed for 2 blade props , sure you can change it to 3 or 4 prop designs , however now the motor will not spin at the same RPMs and could make the motors run hotter or out of spec input readings making the ESC or CPU errors . I am not risking a $3,500 drone to try a different prop .
I didn't think this video had anything to do with RC Cameras. I thought this video was for people who's RC Airplanes always come with 2 blade props, but the Life-Sized, Real-World counterparts always have 3 blade Hartzell Props. They want to convert for realistic, scale looks, but retain flight capability and efficiency. Most of these type of people are definitely doing this mod or they wouldn't even want the plane anymore, lol.
excellent to see this...i left the forums years ago because of way too much 'trial and error' and pseudo science. The latest generation of ducted fans has only just realised that for RC, thrust is king..and now stuff their fans with blades. The vasafans of yesteryear, and some of the wemotecs are faster, and still work if you get the ESC, V, motor right.
Many thanks for this Conor ... great to know the conversion as I prefer 3 blade props ... I assume this conversion equation works in a similar way from 2 to 4 blade but would be DxDXDXDxP / quad root of N-2
Hi, the only thing you need to change is N, the number of blades. The formula would be D x D x D x P x SQRT(4-1). In my example, a 2 blade 9x6 would equate to a 4 blade 7.5x6.
Many thanks Conor 👍👍
@@StartingOutInRC how about 20x10 2blade what is the right number for 4 blade same pitch
What is size of blade bro
Dose HBN or BN propellers decrease rpm?
Hi, I don't use those types on my RC planes so can't advise you on that, sorry.
Ohh now if i stayed 9x6 on a 3 prop will there be a difference in performance? 😁
The speed of the craft and rpm will be low as you'll add 1inch diameter. But the thrust will be higher
Best demonstration !
Good video, wait for US also pls
Great.....!!!
Or you could just simplify it and say if you take your original prop cut it in half take that measurement of half of it and that's what each prop should be on your new three prop blade.....sorry if i didn't word that very well
Interesting but I usually want to keep the prop size the same and change the pitch so the model keeps a good look with the size of the prop. That'll take a little more math I guess.
You can use the same equation, just keep the diameter the same. I get the feeling it'll require a big change to the pitch value to balance the equation.
How to make small motor
How to know how high my homemade Dron will fly?
It will keep going up until the batteries run out! Keeping it under control, which you should do at all times, is down to the range of your radio equipment.
@@StartingOutInRC typhoon h pro can't fly over 122m while dji drone's can fly about 5000m. Why it happens? Isn't there any mathematical theory?
Typhoon H is limited to 122m by its software.
AT 416 THE "music" CAME ON AND I COULD HERE NOTHING YOUR WERE SAYING! WASTE OF MY TIME! OW! IT NOW STOPPED! GOD EXISTS! very good video! "EDUCATIONAL!"
where did you get "educational" from.
@@jch8175 its "NOT!" an "entertaining!" video! its an educational one! one that educates the person watching it and not wasting your time by entertaining you like at "VEGAS!" were we all sing and dance to the drug music/medication music! he clearly is not involved with "NATIONAL GEOGRAPHIC!" were you are completely "entertained" with "beautiful" pictures of the world while playing "RELAXING!" drug music while somebody describes what is happening to you while you are all "messed-up!" from the "relaxing" music! its also difficult to here what a person is saying and its very annoying for no "APPARENT!" reason! this is just a very brief answer to your question! EVER BEEN TO COLLEGE! NOBODY "LECTURES" WITH MUSIC GOING! the word "lecture" means you have to "THINK" with something called "THOUGHTS" about what the person is saying and understand them! with national geographic your simply told the plant is "GREEN!" their are no thoughts! their is no thinking! but they are a very prestigious! organization! for "WHAT THEY DO!" they entertain you!
Not quite what i wanted to know. But hearing such a gebtle irish voice explain something technical... HOW CAN I NOT WATCH... im a man :'(
Why the music though :s
How the rpm will change?
You can use the same RPM. The equation gives you a 3-blade propeller that will place the same load on the motor as the 2-blade
@@StartingOutInRC if I don't use the equation?
If you reduce the diameter by one then you can use the same RPM.
@@StartingOutInRC I mean if I just add another blade without changing anything else then what will be the rpm?
That will depend on the available power. There's a good discussion here on the factors that affect large vs small propellers. www.rcgroups.com/forums/showthread.php?28219-Big-prop-low-rpm-or-small-prop-high-rpm
You must be an engineer? Heheheheh thanks for the schooling that was informative
I'm using my degree as an aeronautical engineer wisely!
@@StartingOutInRC you can tell how you write/draw and the math equation 🤣👍
If that is Chinese 2212 1000kv. Most efficient is 9x4.7. 2 blade carbon prop. And 3 blade is 8x4 ... The best results tested the drag. Rpm Vs thrust output. In practice.. I tested it on 2212 1000kv. 9x6 prop is a bit to big pitch. For 1000kv on 3s. 9x4.7 is spot on efficient for 2 blade and 3 blade I would confidently put 8x4 produced best current draw Vs rpm and thrust output of 1.1kg
WHY MUSIC ?
👍👍👍👍👍👍👍👍👍👍👍👍👍👍
So, if I'm reading this formula correctly, a single blade propeller produces zero thrust. Might be fun to try a negative blade propeller.
There are alot of videos with single blade heli and planes you just have to have a counter weight
Thanks for this. Very interesting.
Watch your lip smacking, though.
I've noticed it too (!) and I only do it when making videos, it's a strange habit. I'm now making a conscious effort to reduce it 🙂
@@StartingOutInRC
It's not that bad.
Thank God there's an easy way...LOL...
I'm more a visual and images right side of the brain kind of guy. Mathematics and logic is for the left side of the brain and no my specialty. To my best understanding... Do using 3 blades insted of two increses the lift for a drone while decresasing battery consuming and improving battery time? The pith of the blade is more pronounced at the center than at the tips. Why is that? Thanks for your explanation on this area.
For the second part of your question you should read Alex Gouthro's comment which describes very well why propellers are shaped like they are. In your first question you have to think about the load the propeller puts on the motor. You can gain small efficiencies by changing pitch or number of blades but the motor may struggle. Adding an extra blade should make the propeller quieter for the same performance, producing 3 smaller pressure pulses rather than 2 bigger ones.
@@StartingOutInRC Thanks so much for the explanation!!! Happy New Year 2020!
"close enough math" thats what nasa said before their rocket went down
Random music at 4:00 which lasts 10 seconds. Son of a bitch
OMG whatever
You could also add up the 2 blade propeller "wing" area and get a three blade of a similar area. Less complicated, more intuitive.