15
votes
Accepted
Do aerodynamics scale for model aircraft?
Aircraft do not scale linearly, for a number of reasons.
Most aerodynamic equations include a speed squared term. If you halve the speed, you only get a quarter of the lift and drag, so models tend ...
- 7,418
8
votes
Do aerodynamics scale for model aircraft?
Elaborating on @Robin's answer with the full effects of the cube-square law.
If we were to construct a model aircraft at half the length of a full aircraft, the model would:
Have half of the ...
- 752
6
votes
Accepted
When flying, how can I identify the orientation of a distant fixed wing model aircraft?
The main way is through 'situational awareness'; if you are flying the aircraft, you should have an idea of what is it doing based on what it has done, and what you have commanded it to do. For ...
- 6,081
5
votes
Accepted
Grinding sound on FPV motor but no apparent damage
It looks like a bad phase to me. Check the resistance of each phase, wire 1 to wire 2, wire 2 to wire 3, and wire 1 to wire 3. If one of those is much higher resistance or shows no continuity, then ...
- 1,220
4
votes
How to limit the power of the brushless motor
Hi mate the design of an ESC with a power limiter is not an easy task.
A purchased ESC will probably have a means of limiting torque or current, but not power. Battery current is probably the best ...
- 481
3
votes
When flying, how can I identify the orientation of a distant fixed wing model aircraft?
Attempting to fly a distant speck of a model in a simulator is a common beginner mistake but it's really just evidence that you need a bit more practice at keeping the model closer to you.
As you get ...
- 7,418
3
votes
Which propeller for these motors for rc airplane
The size of the propeller depends on the voltage of your battery. Higher voltage batteries will make the motor spin faster, so require smaller props to stay within the power limit of the motor.
2200Kv ...
- 7,418
3
votes
Accepted
RC Airplane Fuel Tank Issue
My experience with glow engine models is that the tanks are made to be opened and resealed; the user needs to be able to replace the tubing inside the tank (which deteriorates over time due to ...
- 307
3
votes
Accepted
Is it possible to control an RC plane using reaction wheels?
Yes, it would!
A YouTuber, Thomas Stanton, has actually built a helicopter controlled with reaction wheels in this video!
However, for a fixed wing aircraft, you would also have to consider the ...
- 4,432
3
votes
What technology offers the longest range for RC controls?
The control range depends on the frequency, power and how the transmitter sends the data (the 'mode'.)
Power
More power gives longer range (much like a brighter light can be seen from further away.) ...
- 6,081
3
votes
What technology offers the longest range for RC controls?
If you are not interested in hard, real-time control and can accept some autonomy in the drone, then your best choice is satellite communication. The iridium based modules are lightweight, (45 grams), ...
- 411
2
votes
what kind of propellers should I use for my rc b29?
Work out what scale you're building, and look up the size of the real propellers. Then you can calculate the scale size propeller. You'll need to round it to the nearest inch.
A model like that will ...
- 7,418
2
votes
What technology offers the longest range for RC controls?
To my knowledge, the most readily available consumer long-range RC control system is the Crossfire ecosystem from Team BlackSheep. It makes use of the 868 MHz/915 MHz band and supports RF transmission ...
- 6,063
1
vote
UAV classification
Wikipedia has some drone classifications, based on weight, altitude and degree of autonomy. 100Kg and 2km would be 'medium' or (rather strangely) 'NATO type' (which is slightly lower than 'tactical'.
...
- 7,418
1
vote
UAV classification
For Europe, EASA (the European Union Aviation Safety Agency) classifies UAVs / UAV operations into three categories based on risk, which in turn depend on the weight and capabilities of the UAVs. Any ...
- 208
1
vote
How to couple panel method velocities with boundary layer equations to obtain viscous pressure and lift coefficient?
Hi Mate please see the HFLR5 Site and software that includes also calls to xfoil. As we know what you are asking is not an easy task.
The following example is for an airplane with NACA 2410 airfoil, ...
- 481
1
vote
How to limit the power of the brushless motor
This is done by choosing the correct battery and propeller combination--that's it. Choose a battery. Fully charge it. Then, start testing propellers with a power meter in series with your battery. ...
- 111
1
vote
Do aerodynamics scale for model aircraft?
For a given constant global density, mass grows with the cube of the linear dimension.
Concerning lift, all other things equal, lift grows linearly with the wing area, and the wing area grows with ...
- 111
1
vote
Is it possible to control an RC plane using reaction wheels?
Maybe.
But it would be very challenging in practice. The kinematics of a fixed-wing airplane require it to bank in order to maintain coordinated flight. This is going to cause gyroscopic precession, ...
- 1,892
Only top scored, non community-wiki answers of a minimum length are eligible