1972: Autogyros

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Autogyros
I understand modern autogyros are much more stable, so I've probably angered the autogyro people by impugning their safety. Once they finish building the autogyros they've been working on in their garages for 10 years, they'll come after me.
Title text: I understand modern autogyros are much more stable, so I've probably angered the autogyro people by impugning their safety. Once they finish building the autogyros they've been working on in their garages for 10 years, they'll come after me.

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: Created by an ANGRY AUTOGYRO MAKER - Please change this comment when editing this page. Do NOT delete this tag too soon.
If you can address this issue, please edit the page! Thanks.

On a normal airplane, one will push the yoke forward in a stall or engine out situation, to regain airspeed and to stabilize the plane. On an autogyro, this leads to negative angle of attack, decelerating the rotor, which may lead to a crash. Also pushing the yoke hard forward while flying full throttle may lead to a crash.

Transcript

[A picture of Megan wearing aviator goggles, sitting in an autogyro and holding the control stick. The autogyro is surrounded by sentence fragments, explaining characteristics of it.]
[Clockwise from top left:]
  • Looks like a helicopter, but is nothing like a helicopter
  • Big blade on top is not powered and spins freely [Arrow pointing to it]
  • Can often be flown without a license
  • Cheap
  • Needs a runway to take off, but not a long one
  • Can land vertically
  • Cannot hover
  • Never stalls
  • Extremely safe, unless you do the one thing you instinctively do to escape a stall in a normal airplane, in which case it will crash immediately.
  • Rare in the US, usually homemade. Common in Europe.
  • Sort of like a powered parachute
  • Flies like a plane but is nothing like a plane
[Caption below the frame:]
Autogyros are weird.


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Discussion

Land vertically?

Hi, searching 'autogyro' has led me to find autogyros can't land vertically. Could this be a mistake on Randall's part, or am I missing a joke here?

172.69.186.58 13:55, 26 March 2018 (UTC)

I just read about them on Wikipedia and I see that they can't take off vertically, but there are kinds (possibly all) that can land vertically 108.162.219.76 14:01, 26 March 2018 (UTC)
The Wikipedia article was edited this morning to claim that they could not land vertically, but the edit was short-lived and reverted. So, be careful what you trust. JohnHawkinson (talk) 14:37, 26 March 2018 (UTC)
It appears they can land vertically with the correct wind conditions. Here is a YouTube video: https://www.youtube.com/watch?v=GAoK9zM8FFQ - and they say "Actually it is a 'Zero GROUND Speed Landing' approx. 25 kts headwind".
Here is a YouTube video of a zero ground speed takeoff: https://www.youtube.com/watch?v=Kd7_V4pW--Q
I think the confusion here is that yes, it can land vertically: for that matter, so can any airplane. What matters isn't ground speed but airspeed, and as long as there's as much headwind as the landing airspeed of the aircraft, it will land vertically. Now, with fixed wing airplanes the landing speed is at least 40-50 mph, and you don't often find headwinds like that. The much lower landing airspeed of an autogyro makes that feasible. Gbisaga (talk) 21:26, 26 March 2018 (UTC)
"Landing vertically"...having so little forward airspeed on touchdown that it is negligible108.162.216.208 23:40, 26 March 2018 (UTC)
I disagree with this. If that were the case, an autogyro could NOT land vertically or anything close to it. I think it's clear that "vertical" refers to movement relative to the ground, as movement relative to airflow is invisible. I'm having a hard time finding hard numbers on minimum airspeed for an autogyro (and unlike fixed wing aircraft, I've never flown one myself, so I don't have practical experience to fall back on). However I've seen a typical autogyro's best rate of climb speed is 50-50 mph, versus almost 70 for a 152; so I'll project about 30 mph for a minimum speed in landing configuration. Landing in that kind of headwind is certainly not unreasonable (though it would probably be not that much fun). Gbisaga (talk) 12:56, 27 March 2018 (UTC)
I'd expect an autogyro to be capable of landing the same way a helicopter with an engine malfunction lands - autorotate the rotor to store energy and then stop while relying on the rotor to slow the descent. Does not sound like the safest of procedures, but it certainly gives you a vertical landing. Mat (talk) 08:30, 27 March 2018 (UTC)
Doesn't the downward motion of the autogyro during descent contribute to the autorotation of the rotor, thereby providing lift while descending even through air that is calm laterally? 162.158.154.43 14:29, 27 March 2018 (UTC)

Thanks for the comments, guys. I'm not the original commenter, but I had a severe misunderstanding of what "landing vertically" meant. 172.68.26.71 13:54, 27 March 2018 (UTC)

Cannot hover?

I would assume that autogyros can hover in some conditions (i.e. in a headwind). This is the same argument as the one for "Land Vertically?"; namely that it's the wind that matters. Is Randall wrong here or is this just an impractical edge case? Here is a YouTube video Kosak2000 (talk) 15:58, 27 March 2018 (UTC)

It can hover in the sense that any fixed wing airplane can hover - by having a fast enough headwind. I've "hovered" in a Piper Cub before - even flown backward! But that isn't the conventional use of "hover" by aircraft pilots. Hover it meant to refer to purposeful powered flight over a stationary spot 'with no wind'. Such as a Helicopter can do. An autogyro cannot do this, as it must maintain forward movement (compared to the air) to maintain lift. However, with some "trick piloting," you can vertically land an autogyro. You're not hovering because you're not holding your altitude, but if you come in with some forward speed and high-ish descent rate, you can flare a few feet above the ground to a horizontal stop, turning your formerly forward speed in to slowing the descent rate to an acceptable descent rate to land at. 172.68.174.94 03:21, 28 March 2018 (UTC)
Trivia

First successful flight of an autogyro was in 1923, so they have been around for close to 100 years. Rtanenbaum (talk) 17:04, 26 March 2018 (UTC) The 1981 movie Mad Max II prominently featured an autogyro as part of the action. Rtanenbaum (talk) 17:04, 26 March 2018 (UTC) Also James Bond 007 flew the autogyro 'Little Nellie' in " You Only Live Twice". Reputedly prompting a bit of an autogyro revival. RIIW - Ponder it (talk) 17:46, 26 March 2018 (UTC)

There was also an autogyro in the 1980 adaptation of Ray Bradbury's "The Martian Chronicles" --Mr. I (talk) 00:51, 30 March 2018 (UTC)

First of all, I've converted section headings to bold labels - we should avoid them in discussion content. Secondly, my take on how to order the labels around the autogyro is down the left side, then across the top, and finally down the right side. I realize it's entirely up to the reader, but that order makes the most sense to me instead of clockwise - the text on the lower-right seems to be climactic in a strange Randell-esque way. Ianrbibtitlht (talk) 18:15, 26 March 2018 (UTC)

Agree with your entire comment, and have changed the order in the transcript --Kynde (talk) 20:03, 26 March 2018 (UTC)

Has Megan been seen wearing goggles before? Herobrine (talk) 23:05, 26 March 2018 (UTC)

"Powered parachute"? Sounds to me like this awesome thing. Fabian42 (talk) 08:50, 27 March 2018 (UTC)

It's actually this similar awesome thing and I've updated the main descriptions to link there. -boB (talk) 20:14, 27 March 2018 (UTC)
Section Headings

Re-converted section headings to bold labels in discussion content - please avoid re-adding them because they can interfere with auto-layout templates in the explainxkcd page system. Ianrbibtitlht (talk) 17:04, 27 March 2018 (UTC)

I feel like the "Not popular in the U.S., popular in Europe" should say "Self explanatory", then link to a page showing stats about popularity. (I can't find anything quickly, and am in a hurry right now). NiceGuy1 (talk) 07:19, 30 March 2018 (UTC)

Stack Exchange question

FYI: This xkcd was a subject on the Avionics Stack Exchange site: Is this XKCD comic list about autogyro features accurate? --PeterMortensen (talk) 12:46, 30 March 2018 (UTC)