# Questions tagged [model-aircraft]

Questions about "Model Aircraft" and the regulations which govern them. Model Aircraft are a specific type of unmanned aerial vehicle which are only flown for hobby or recreational (non-commercial) purposes, and flown within the visual line of sight of the operator at all times.

30 questions
32 views

### Load testing a model glider wing

I wish to load test a model glider wing. The standard static load test methodology using sandbags on the upturned wing would be difficult as the chord of the wing is small - it will be difficult to ...
107 views

### Aerodynamics and fuel consumption of a powered glider

I want to optimize the flight distance of a powered glider model airplane, without the use of soaring. I've studied some aerodynamics books, but still feel unsure about my conclusions. Please tell me ...
47 views

### When calculating lift, using the the NASA lift equation, can any value be increased, ie. velocity or surface area, for increased lift?

I am trying to understand the breakdown of the NASA lift formula, which is written as such $L = C_L \frac{\rho v^2}{2}A$ If I take for example CL=0.87, v=20m/s, ρ=1.22kg/m3, and A=9.02m2, my ...
345 views

### Does the required torque to spin a propeller increase with RPM?

I‘ve currently been experimenting with different propellers: 12x12 prop, 16x12 prop (both two blades) and a 22x14 (6 blades) prop. They were propelled by a 2.4 kW electric motor with 260 kV on a 6S/...
98 views

### In xflr5,how is the value of Fz calculated?

I am building an conventional plane with AR=6 and I find the wing area,A.So I have selected an airfoil for building my plane that is sd7062. Using xflr5 I got a cl vs alpha graph and I took the cl ...
92 views

### Where can I find the best site to learn aircraft design on a small scale? [closed]

I am undergraduate student still trying to figure out a lot about Aerodynamics and aircraft design. I am learning how to design rc planes. So the thing I know the weight of my plane which is between ...
146 views

### Will leaving the ducting on the propellers attached to a DIY aircraft give it more thrust? [duplicate]

I'm not sure if its the right place, I have a problem with a flying thingy, and you like flying thingies, don't you? I will be trying to add some means of propulsion to my friend's styrofoam plane (...
129 views

### What is the effect of fuselage weight on a model glider?

I've built a model glider and wanted to see the effect the weight of the fuselage had on its performance. It flew the further with more weight which seems counter intuitive. I can exert more force ...
131 views

### What are the equations of motions for parafoils?

I want to use the following equations so as to describe the motion of parafoil \left[ {\begin{array}{*{20}{c}}{\dot x}\\{\dot y}\\{\dot z}\end{array}} \right] = {V_a}\left[ {\begin{array}{*{20}{c}}{\...
246 views

### How high can I fly a model aircraft under 14 CFR 101 rules?

For a UAS operated recreationally, may altitude exceed 400 AGL? AMA rules state in several places that flight above 400 AGL should be avoided. And close to airports there is a more firmly worded ...
223 views

### How to proceed in designing a catapult glider with maximum flight distance? [closed]

As a basis for this question, take the following catapult glider: http://www.guillow.com/spaceshuttle.aspx This model has low aspect ratio wings, a thick wing section and a relatively wide fuselage, ...
11k views

### Why do model aircraft fly and maneuver so differently from real aircraft?

I recently viewed on Youtube many videos of small and giant models of airplanes. In some cases they are small (for example an A330, 1 meter long) and in others they are huge (for example an A380, 5 ...
847 views

### Which airplane is this lego model?

I'm wondering about the type of jet in this lego kit: https://shop.lego.com/en-US/Airport-Air-Show-60103 One of the jets appears to be an F-18 (the one with twin tails, of course) but I can't place ...
393 views

### What knowledge is needed to build a small aircraft?

It is my dream to make a basic flyable small scale aircraft (the size of a model aircraft). What is the basic knowledge needed to be able get started in the first place? In particular, I would like ...
160 views

### How is the required motor power calculated for a quadcopter?

I've been trying to find the required motor power for a quadcopter. I first calculated drag power and then I made a linear trend line for motor power against motor weight. I made the motor power 1.5 ...
149 views

### Feasibility of using secondary props to generate power on an electric model aircraft [duplicate]

Beginning with the aeroplane itself, it is a small, fixed wing model aeroplane, reminiscent design-wise to a Cessna 172. It is completely battery powered and has a primary prop attached to a motor ...
179 views

### Is it legal to build and fly an international aid drone?

Is it legal to build and fly a scale 1m:20cm Boeing C-17 for use in flying from the U.K. to other countries to deliver aid in places that are hard to reach? For example, on top of a large hill where ...
1k views

### Why is white light more visible than red and green on this Cessna model on a sunny day?

Source: https://i.ytimg.com/vi/hNgu1vypV3g/hqdefault.jpg VS Why is the white Landing light more visible on a fine sunny day and not the other two? I would have assumed the Red one to be most visible ...
729 views

### Why does this plane not pitch up after a dive?

I've tested my RC plane yesterday. It's a canard. After hand launching, the plane goes straight, then I change the elevator to go down and it's going down, but when I pitch up the canard doesn't work ...
415 views

### How can I get started on a winglet design for a small remote controlled aircraft?

I'm a member of a student competition team, we design light aircraft (total airplane overhead area is limited to 0.9 m²) capable of carrying higher payload. The competition also limits the takeoff ...
10k views

### How can an aircraft hover almost vertically?

(Source: https://fat.gfycat.com/) The aircraft in this GIF (although being an RC plane) seems to be flying vertically, just meters above the ground. How is this possible? How is it possible to ...
3k views

### Do quadcopter propellers break the sound barrier?

I recently bought a quadcopter and noticed every time I fly it there is this weird buzzing noise. I have heard this noise on other quadcopters around the same size as mine(4in by 4in). On an airliner ...
434 views

### Does the direction of counter-rotating props affect efficiency?

From my brief Wikipedying, if counter-rotating props' tops go towards each other, each has a reduced P-factor so the loss of either engine won't yaw the aircraft as hard as if the bottoms come ...
2k views

### Has the FAA banned FPV for model aviation?

On the FAA website the FAA says that you should not fly your model aircraft out of line of sight. Does this mean you cannot use FPV goggles?
979 views

### How can you calculate the gliding distance for a remote controlled jet?

Is there a way to calculate the gliding distance for a remote controlled (RD) jet aircraft, in case of engine failure? We have some telemetry data on the model, giving us speed and altitude so as to ...
683 views

### What airfoil design is needed for a 4 m wingspan soaring plane?

I’d like to build one that is heavier than a F3J plane and it will be similar to NASA’s soaring plane of the "Autonomous Soaring Plane" project. What kind of airfoil do I need? Simply scaling a normal ...
2k views

### What is the maximum altitude allowed to fly a model plane/helicopter in England?

What is the maximum altitude I'm allowed to fly a model plane or helicopter in England?
2k views

### Could you use radial blowers to propel a model aircraft?

I was inspired by stealth planes like the Boeing Phantom Ray: I'd like to make a model aircraft that's as thin as possible, and has integral engines that are not visible from the outside. I have been ...