Linked Questions

43 votes
6 answers
21k views

Can a helicopter stand on the ground upside down on its rotor head?

From what I understand the rotor head needs to be strong enough to hold the craft weight hanging below it, and sounds pretty strong. The blades however look quite fragile (for a piece of metal). In ...
PTwr's user avatar
  • 549
19 votes
4 answers
13k views

Why are there no helicopters with the rotor mounted on the bottom?

Downwash from the rotor of a helicopter creates drag on the helicopter body acting against the lift force of the rotor. Why are there no helicopters with the rotor under the main body of the ...
Andreas Pichler's user avatar
26 votes
2 answers
5k views

Are helicopters easier to fly nowadays due to computers?

4 decades ago, someone who seemed to know about helicopters said that hovering in one was like balancing on a ball (like bears do in a circus). But it seems like by using computers hovering and other ...
releseabe's user avatar
  • 363
28 votes
2 answers
7k views

Are helicopters aerodynamically stable?

On a fixed wing aircraft, if the aircraft's attitude is disrupted by a small angle and the controls are let go, it will slowly right itself to straight and level, due to built-in aerodynamic stability ...
kevin's user avatar
  • 39.7k
20 votes
2 answers
4k views

How does this RC helicopter keep itself upright?

I have this (cheap, beginner-level) RC helicopter: It has 3 controls: one for climbing and descending (collective throttle), one for yawing (differential throttle), and one for pitching (the tail ...
Tanner Swett's user avatar
  • 5,771
5 votes
4 answers
2k views

Can any helicopters use negative collective to descend rapidly?

On a helicopter, the collective is used to adjust the attack angle of all the main-rotor blades in the same direction by the same amount, causing the amount of lift generated to increase or decrease ...
Vikki's user avatar
  • 28.3k
3 votes
4 answers
4k views

Why does the helicopter's nose go down when the cyclic is pressed forward (in a hover)?

Helicopters have hinges on top of the rotor mast, allowing the rotor to be tilted longitudinally (forward/aft) or laterally (sideways). Why does the helicopter fuselage tilt up/down when the cyclic ...
Koyovis's user avatar
  • 61.6k
3 votes
2 answers
2k views

Why do helicopters typically have blades at the top?

This question has several great answers showing that it's perfectly possible for a helicopter to fly with its blades underneath the rest of the aircraft. There are some obvious issues with having a ...
LangeHaare's user avatar
3 votes
4 answers
1k views

In helicopter's forward motion, how is the forward pitching moment taken care off?

When the rotor disk is in the position shown by the dashed lines, the net Lift is at an angle. It should produce a forward pitching moment about CG (Center of gravity). That can cause the helicopter ...
Raj Arjit's user avatar
  • 268
0 votes
1 answer
376 views

Does the stability of a mass change if the center of gravity is above or below the point of thrust? [duplicate]

I was wondering if it makes any difference if the mass is balanced above or below the point of thrust. See image below for clarification: In the image you can see two configurations. The red arrow / ...
FutureCake's user avatar