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171 votes
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Why does XKCD say that autogyros will crash if the pilot reacts to a stall as in a normal airplane?

That one thing is to unload the rotor too much (i.e. "push on the stick"): From explainxkcd: ... Unfortunately, as soon as the rotor stops spinning, the whole aircraft falls like a brick ...
Wayne Conrad's user avatar
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82 votes
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Is this XKCD comic list about autogyro features accurate?

Flies like a plane. To a certain extent in that the controls are plane-like, you do not have helicopter controls (no cyclic, etc.), but you also do not have wing control surfaces, so in some respects ...
AndyW's user avatar
  • 1,171
30 votes

Why does XKCD say that autogyros will crash if the pilot reacts to a stall as in a normal airplane?

This is a well known problem with gyrocopters. The first answer was partially correct in that the problem was caused by pushing the stick forward and unloading the rotor. However, the problem wasn't a ...
scientious's user avatar
23 votes

Why does XKCD say that autogyros will crash if the pilot reacts to a stall as in a normal airplane?

I believe what the comic is referencing is Mast Bumping. Rotor blades are very flexible, and for a bunch of reasons, are free to pivot around the mast.(The shaft the blades are spinning around) In ...
Smoores02's user avatar
  • 239
18 votes

Is this XKCD comic list about autogyro features accurate?

The "needs a runway to take off" statement is historically true of most autogyros, but many modern ones can take off vertically. It's called a "jump takeoff." It works by flattening the blade pitch ...
Orv's user avatar
  • 181
12 votes
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Why do autogyros exist?

Autogyro blades have a higher airspeed than the aircraft that is carrying them, so they can generate lift even when the aircraft speed is low. They fly as if they had a wing the size of the whole disk,...
Robin Bennett's user avatar
8 votes

Is this XKCD comic list about autogyro features accurate?

Re the "Can often be flown without a license" this is true in the US for certain types of gyro - small, one-person craft which are classed as part 103 aircraft. All the more modern, useful ones that ...
chipchap42's user avatar
8 votes
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Can an Autogyro with wings survive a rotor mechanical failure? Will it be safer?

That is a very broad question and covers many topics, but I will try to answer as best I can and not miss anything. A quick note on the wings. Adding wings as a safety aspect to the aircraft kinda ...
Dawn Breaker's user avatar
7 votes

What are the advantages and disadvantages of autogyro aircraft?

Image source From the same website: Zooming through the sky in something that looks like a flying chair, isn't for the faint-hearted. These aircraft look like a cross between a small ...
Koyovis's user avatar
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7 votes

Why autogyros use pusher-, whereas, piston-engined planes use puller-configuration?

Pitcairn PCA-2 - By NASA/NACA, LARC [Public domain], via Wikimedia Commons The original autogyros were tractor (google Cierva/Pitcairn). The big thing with autogyros is thrust line relative to the ...
John K's user avatar
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6 votes

Can anyone identify this Autogyro?

It looks like a Kellet K-3, I believe... Photo from 'Cierva Autogiros', by Peter Brooks.
xxavier's user avatar
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5 votes
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Would this concept of Autogyro/Gyroplane be efficient or practical?

There's no sensible reason to use ram air turbines to power the rotors on a craft like a gyroplane. The rotor is already powered directly by the airflow -- essentially "gliding" in and ...
Zeiss Ikon's user avatar
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3 votes
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Is there a way for the helicopter rotor to get its power half by wind, half by engine?

The problem is that as an autogyro, the air is going through the rotor from below, and as a helicopter, the air is coming from above and it has to be one or the other. In any case, gyroplanes don't ...
John K's user avatar
  • 132k
3 votes

Grand Canyon flying minimum altitudes

The rules for operations in the Grand Canyon Special Flight Rules Area (SFRA) are governed under 14 CFR Part 93, Subpart U. Please review these rules here and all applicable GCSFRA NOTAMS prior to ...
Romeo_4808N's user avatar
3 votes

What are the uses of gyroplanes?

I also want to mention these advantages (in addition to the lower operational cost): Easy to fly and enjoy the flying experience. Because it is in constant autorotation it can't stall. It's simpler ...
Jesús Martín Berlanga's user avatar
3 votes

How does the forward speed of an auto-gyro relate to the rotation speed of the rotor during auto-rotation?

An autogyro flies at constant rotor RPMs. In vertical autorotation, that is a particular case, the rotor revs may be 10-15% less, but in straight and level flight, the rotor revs are higher, and ...
xxavier's user avatar
  • 11.1k
3 votes

Is it possible to have dual contra-rotating rotors on a gyrocopter or gyroplane? Are there disadvantages that would outweigh the extra lift?

You can get additional lift with a larger rotor, without going to the extra complication of having two of them. Present-day autogyros are very light machines that have more than enough with one rotor. ...
xxavier's user avatar
  • 11.1k
2 votes

Can an Autogyro with wings survive a rotor mechanical failure? Will it be safer?

Sure those wings would help, but if the 'mechanical failure' of the rotor involved an important imbalance, such as the loss of a blade, the machine would be difficult to control, wings or no wings... ...
xxavier's user avatar
  • 11.1k
2 votes

What are the uses of gyroplanes?

The gyrocopter is cheap, versatile, and as easy to operate as an off-road motorcycle. What can it be used for? For everyone's daily ride to work. The owner of Quobba Station in Western Australia owns ...
Koyovis's user avatar
  • 61.8k
2 votes

What are the applications, advantages and limitations of Gyrodyne rotorcraft?

The compound helicopter similarly has a separate propulsor for thrust. The gyrodyne differs from it in allowing the lift rotor to autorotate without power during forward flight. Both are capable of ...
Guy Inchbald's user avatar
  • 7,062
2 votes

Why do autogyros exist?

The autogyro was invented as an aircraft that cannot stall - a friend of the inventor was killed in an aircraft stall accident. The usefulness of the autogyro is that it was the necessary step on the ...
RAC's user avatar
  • 4,616
2 votes

Clarification on autogyro thrust formula

Weight is a force by definition. Its SI unit is newton. In most circumstances, weight is equal to $F=mg$. The quantity in kilograms is called mass. In colloquial speech it is often called weight ...
Sanchises's user avatar
  • 13.4k
2 votes

Clarification on autogyro thrust formula

In vertical autorotation, with a constant sink velocity, the lifting force produced by the rotor is exactly equal to the weight of the gyro, since any difference between weight and lift would cause an ...
xxavier's user avatar
  • 11.1k
2 votes

Would an Autogryro/Gyrocopter with wings be safer than a normal autogyro in a negative G situation?

Maybe. A big issue with a negative-g situation in an autogyro is loss of longitudinal control caused by the loss of drag on the rotor. The rotor drag provides a lot of nose-up moment, and the loss of ...
Chris's user avatar
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1 vote

Sub-ideal Autorotation in Rotorcraft

Autorotation in helicopters is rarely ideal, with net rotor torque = 0, because some energy is drained from the turning blades to feed the tail rotor. There's, however, a continuum between the ideal '...
xxavier's user avatar
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1 vote

Autorotation: Positive Pitch during descent phase possible?

During autorotation there are two main angles which are important, the inflow angle created by the rate of descent flow and rotational airflow plus the pitch angle (normally minimal on initial entry ...
Rob Wilkinson's user avatar
1 vote

How to calculate the amount of thrust of a autogyro during auto rotation?

In auto-rotation, either flying level, or with a constant sink speed, the vertical component of the thrust provided by the rotor is exactly the same as the weight of the gyro... In Wikipedia https://...
xxavier's user avatar
  • 11.1k
1 vote

Is it possible to have dual contra-rotating rotors on a gyrocopter or gyroplane? Are there disadvantages that would outweigh the extra lift?

Look at rc twin rotor gyros. They perform quite well. Instead of having articulated blades they are fixed and counter rotating at the end of opposing booms .The rotors are shorter and spin much faster ...
Chris's user avatar
  • 11
1 vote

Is it possible to have dual contra-rotating rotors on a gyrocopter or gyroplane? Are there disadvantages that would outweigh the extra lift?

I've long thought that a dual-rotor gyroplane, where the rotors are mounted side-by-side with a "coordination shaft" between them (such that they mesh) would be a good idea. Look at the Flettner and ...
Meower68's user avatar
  • 1,257

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