15

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 to be lighter and less powerful than you'd expect. If you make a plane with half the wing span, it only has a quarter of the wing area. So now a half size model ...


10

There's no magic technology, it's just a difference in design goals. FPV drones are designed for speed, performance and robustness, DJI drones are designed for duration and carrying a gimbled camera. Larger, slower turning rotors are more efficient at producing lift but have a lower top speed. That's why helicopters can hover and propeller planes with the ...


10

You might be able to write custom flight control software for a multi-copter that would simulate this. You might get close just by radically limiting the pitch and roll rates and being gentle on the throttle. In either case it wouldn't be intrinsic to the design. If you want smooth, soaring flight, you'd be best to build a fixed wing model with a fairly ...


9

(Edit: The original version of this question asked about "drones" in general. This answer was based on the question pre-edit, hence the clarification of drones vs. quadcopters.) First, a word of clarification. A drone is just any unmanned aircraft. The specific type of drone you described in your first paragraph is called a quadcopter. Now, if you ...


8

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 wingspan as the full aircaft Have a quarter of the wing area Have an eighth of the mass Counter intuitively, this means that the model has more surface area per ...


5

This is a good question. In short, While DJI drones certainly have a lot of engineering and design put into them, the way they achieve long flight times is no secret. The DJI drones' long flight times are largely due to the high capacity batteries, motors, and propellers used. Although, there are many smaller things that also affect flight times. Probably ...


3

The premise of your question is based on fairly limited observation of aviation. First there are many fixed wing "drones". They just haven't been as prevalent in the consumer market as in the segments of the hobby market that grew out of the longstanding R/C aircraft hobby, and in the professional market. Next, in terms of rotary wing flight, it's ...


3

Lower kV motors will spin more slowly but with more torque. Spinning more slowly (with the same prop) will give you less thrust and less power (and thus lower current) at full throttle. However, a well setup quad doesn't spend much time at full power, especially when you're considering your total flight time. The amount of thrust required to fly is still the ...


2

"Drones are small helicopters": False. Drones are fixed prop and that mechanical difference alone places the devices in a unique category. The actual differences are many. It should also be mentioned that "drone" covers a wide range of devices, the proper term would be multirotor or specifically fixed prop multirotor. "They cannot ...


1

Drone capable of smooth, gliding, birdlike flight? Possible, and done. (Missiles optional)


1

I have built and owned plenty of racing and photo drones. DJI is one of best for photo drones.There is a big difference in a racing drone that uses ESCs and motors that take a lot of power to fly at high speeds and for quick maneuverability and a photo drone which does no need to use as much power. They have designed the camera drones to use lower RPM speeds ...


1

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 the square of the linear size. For similar reasons, drag grows with the square of linear size too. And concerning power required, it grows with the power 3.5 of ...


Only top voted, non community-wiki answers of a minimum length are eligible