Linked Questions

4 votes
2 answers
240 views

Can the measured thrust of a propeller be greater than the max thrust predicted by Froude's theory?

Can the measured thrust of a propeller be greater than the maximum possible thrust predicted by Froude's Propeller Theory? Is Froude's theory reliable in practice regarding the upper limit of the ...
topaz's user avatar
  • 41
2 votes
2 answers
512 views

How much is a swashplate system more energy efficient than a fixed blade system for the same load

When reading about the lifting capacity of swashplates (as found in helicopters) vs fixed blade systems (as found in e.g. DJI drones), I read a lot of comments about the fact that the bigger rotors of ...
Arie's user avatar
  • 117
0 votes
2 answers
965 views

Would large, low aspect ratio fan/propeller blades be more efficient? Why not?

With reference to this answer We read in the above that accelerating a larger mass of air by a smaller amount is (theoretically) more efficient. This is an advantage of a larger propeller than is ...
Abdullah is not an Amalekite's user avatar
28 votes
1 answer
18k views

Is there any equation to bind velocity, thrust and power?

I am designing a remote controlled airship. I will tune it so that the lift given by Archimedes' Principle will exactly balance the weight of all the structure. It will be propelled by brushless ...
Matteo Monti's user avatar
7 votes
1 answer
695 views

How much energy/prop efficiency does the e-volo copter sacrifice by having a smaller propeller?

It seems like on an electric aircraft, it would be very important to have a high energy efficiency. Wouldn't the e-volo copter be much less efficient due to the small radius of the propellers when ...
David's user avatar
  • 1,359
4 votes
1 answer
616 views

Matching the Drag Equation to Real Airplane Data

I am trying to compute airplane performance for a piston-driven airplane with constant speed prop using the standard equations for Lift, Thrust and Drag. I have found that there are a couple of useful ...
Phil Crowther's user avatar
4 votes
1 answer
3k views

Is there a special way to calculate the (parasitic) drag produced by the propeller?

Is there a special way to calculate the drag produced by the propeller? Can I compute it with the standard formula for parasitic drag, with the circular area of the propeller as the wetted area? To ...
Simon Ravelingien's user avatar
3 votes
1 answer
2k views

What is the difference between types of propeller? [closed]

I have been noticing almost every Multirotor vehicle uses a single thin double-bladed propellor on each axis. And yet clearly, there are some that do not fit the norm. Can someone explain what the ...
iNeedToMakeBetterQuestions's user avatar
2 votes
1 answer
134 views

What is the range of ratios between optimal propeller efficiency and true propeller efficiency?

In https://aviation.stackexchange.com/a/15383/20394, the optimal prop efficiency is given as: $$\eta^{opt}_{Prop} = \frac{1 - \frac{\Delta v\cdot \left({v_{\infty} + \frac{\Delta v}{2}}\right)}{d_P^2\...
Kenn Sebesta's user avatar
  • 5,172
2 votes
1 answer
2k views

Is there a mathematical formula to find the most efficient propeller? [duplicate]

Is there a mathematical formula to find the most efficient propeller? Is a five-blade better than a four-blade? Does software exist to aid in the calculations there?
AirbusLover's user avatar
1 vote
1 answer
183 views

Is flow attached at fixed propeller blade at every RPM / speed conditions?

Propeller blade AoA depends on tangential veloctiy caused by rotation and forward speed "head wind". If propeller has fixed pitch is flow attached on blade at every RPM / speed conditions? ...
user avatar
1 vote
1 answer
94 views

What are some first-order drag approximations for airframe/propwash interactions?

What are some first-order drag approximations for airframe/propwash interactions, both for dynamic flight and for static thrust, in a traditional tractor configuration?
Kenn Sebesta's user avatar
  • 5,172
1 vote
1 answer
416 views

How energy efficient is an aircraft take off?

How much work is generally done by an aircraft (e.g. B737NG) in order to reach V_rotate, and how does this compare to the energy content of the fuel that is used?
JNld's user avatar
  • 11
1 vote
1 answer
3k views

What is the Efficiency of Cessna-150's Propeller?

From that Cessna-150's data, it used Continental 0-200-A 100 HP (75 kW) at 2,750 RPM and with Fixed Pitch propeller with its diameter=69 inches. If power is delivered maximum to the propeller (through ...
AirCraft Lover's user avatar
0 votes
1 answer
2k views

static thrust vs. prop RPM data?

edit: question was too long, and is actually simple, so I removed unneccesary description Background: There are many questions here about: propeller efficiency changes to thrust when it is dynamic ...
ivanantuns's user avatar

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