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I'm looking to find the amount of lift produced by a 27 inch diameter, 12 inch pitch, two-blade propeller spinning facing the ground. Are there any datasheets that show the amount of lift given at any rpm?

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    $\begingroup$ Thrust generation also depends greatly on the propeller pitch, not just the diameter. $\endgroup$
    – ifconfig
    May 15, 2020 at 3:28
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    $\begingroup$ Thank you for visiting Drones.SE! In order to get the answer you are looking for, please add a few more details about the specifications of the propellers. Information like pitch (as mentioned above), number of blades, and any other information you have on the propellers you want information for. The more information you can provide, the better the answers will be. $\endgroup$
    – Jacob B
    May 15, 2020 at 3:36
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    $\begingroup$ @GabrielKusiak Just saying that an answer can specify for any pitch doesn't help. In order to get a good answer, you'll need to be asking about a specific diameter and pitch combination, or else any answer would have to spell out every possibility under the sun, which isn't desireable. $\endgroup$
    – ifconfig
    May 15, 2020 at 3:55
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    $\begingroup$ @ifconfig ok I fixed it. $\endgroup$ May 15, 2020 at 4:28
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    $\begingroup$ @ifconfig I've found a prop 27 inch diameter, 12 inch prop. I also edited the question $\endgroup$ May 15, 2020 at 4:42

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There are too many factors to be able to give you a precise plot. All the below have major impacts on propeller performance:

  • Activity factor
    • A blade with a thicker chord will generate more thrust, but have less efficiency
  • Airfoil selection
    • Prop airfoils change as a function of radius. Some airfoils are good (bad) at low Reynolds and/or low Mach, but are bad (good) at high Reynolds and/or high Mach
  • Proximity to ground
    • If you're close to the ground, pushing air at the ground, then you have a good efficiency bump from ground effect.

However, https://www.apcprop.com/files/PER3_27x13E.dat is a good first step. The change in pitch from 12" to 13" is not going to dramatically change matters, and probably has less of an effect than flying in ground effect or airfoil changes.

You can also compare to https://www.apcprop.com/files/PER3_26x13E.dat, which reduces diameter by an inch, while increasing pitch by an inch. You will likely find that a theoretical APC 27x12 will be in between the two in terms of performance.

I hope this is helpful. Ultimately, once you get close enough to your desired theoretical performance there's no option but to try a few blades out for empirical results.

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