3121: Kite Incident

Kite Incident

|< < Prev #3121 (July 28, 2025) Next > >|

↓ Skip to explanation ↓

Title text: Detectives say the key to tracking down the source of the kites was a large wall map covered in thumbtacks and string. 'It's the first time that method has ever actually worked,' said a spokesperson.

|< < Prev Random Explanation Next > >|

Explanation

In this comic Megan is setting up a kite as Cueball arrives. Megan sets up the kite using a fishing line, which is unorthodox but not unheard of. Because the connection between the holding point and the lofted kite will form a catenary hanging down, after paying out sufficient line toward a kite increasingly far downwind, the line starts to dip and possibly touch the ground. Cueball suggests adding another kite at that point, after which they can then pay out more line and keep the line raised off the ground for additional distance.

They then get into a loop of adding more line to accommodate a stock of kites, and then more kites to support the line, until the kite chain reaches ludicrous proportions. The kites become so numerous and high-flying that they eventually blow in a circle around a significant part of the planet, following a jet stream. A circle on the surface of the Earth that follows the line of latitude where Randall lives is about 18,500 miles long, though a circumpolar jet-stream would curve into higher and lower latitudes to possibly add a lot more distance (as well as being at a higher altitude, which would add a more predictable fraction to its length). If the kites have been dragged into a much smaller circle as the result of a kite and/or its string getting caught by an airplane, there's no evidence of this to either the comic's characters or to ourselves, and travel purely by extensive (albeit slower) atmospheric movement has been featured before. Modelling the line as a straight line stretching 15 degrees above the horizon, Megan has spent over 38km of fishing line by the time the first kite reaches the jet stream at 10km high, but the mean separation of kites is possibly not particularly far, based upon the heights of the figures in wider shots, and Megan has lost count of how many they deployed, anyway. The curve of the hanging tethers would be highly dependant upon the tension between the two points of suspension, as would the ability of any given kite to fly, but there is not enough clear information to discern to what limits these (and the fishing line) might constrain the scenario.

The sirens in the second-to-last panel refer to a visit by some law-enforcement agency. The string of kites circling the Earth has interfered with international air travel. Although the mass of any given kite and the presence of such a relatively light and fragile tether should not cause too much difficulty for the majority of airliners if their wing or body collides with the kite-chain, the danger of a kite being ingested into the engine would preferably be avoided out of an abundance of caution. This is true even if the presence of kites is known to be not a more solid danger rather than a mystery and/or perceived threat which can lead to air travel to be shut down. (Of course, with xkcd physics, the pilots may have been concerned that snagging on the kite string would pull Megan and Cueball off of their feet.) Regardless of the actual degree of danger, the authorities react accordingly, and events culminate in Megan and Cueball being forced to issue a formal apology. Having their lawyer there might indicate they won't get away with just an apology, but maybe this is to show they meant no harm, to decrease the penalty they will face.

The title text alludes to an investigation technique seen in many types of media where the investigator pins text and photo evidence to a board, connecting related evidence with string. This technique is also made fun of in 2244: Thumbtacks And String. Though often good enough for fictional purposes, at least to the extent that the plot demands, the text indicates that real-world uses of 'string on a map' to discover a useful result have not actually been successful. But in this case, the string on the map would be there to indicate the actual extent to the string in the air, probably from various reports received from around the world, and apparently it had successfully led to the discovery of the location from which the string originated on the ground and the subsequent intervention against the duo's excessive kite-deployment activity.

Kites have been a recurring topic on xkcd since the early days. It has been three years since the last comic featuring kites, 2632: Greatest Scientist, six years since Cueball put one up, in 2208: Drone Fishing, and 10 years since Megan did so, for 1614: Kites.

Transcript

[Cueball approaches Megan from the left. Megan is flying a kite, with the line attached to a spool.]

Cueball: Ooh, flying a kite?

Megan: Yeah. I found this big spool of fishing line in a closet.

[In a silent panel, Cueball and Megan are seen from further away, indicating that the kite is flying higher.]

[Cueball and Megan are seen from yet further away, indicating that the kite is flying still higher.]

Cueball: Are we allowed to fly a kite this high? Should we Google whether there are rules?

Megan: Eh, it's probably fine.

[The line held by Megan leaves her hand almost horizontally before curving up. Cueball stands a little way downwind his hand up to the string, above head-height, as if supporting/stabilising it or testing its tendency to stay up.]

Megan: The string is really starting to sag.

Cueball: Maybe we could attach another kite? I'll go get one.

[A new kite is attached just above the line, supporting it higher in the air, Megan's held end now leading up to the point it is joined.]

Cueball: It worked!

Megan: Nice!

[Megan is feeding out line from a partly depleted spool, via a peg/ground anchor, with a knot visible a short way up the rising cord. Two further empty spoole are seen on the ground. Cueball is approaching with a box.]

Cueball: I bought another package of string.

Megan: Oh good, these spools are almost empty.

Megan: I think we're in the jet stream.

[Three empty spools, one spool in use and one unused spool surround Megan and Cueball, with one supporting kite visible on the line that Megan is still feeding out.]

Cueball: How many kites are on there now?

Megan: I've lost count.

[Another silent panel, zoomed out to see at least a half self-supporting "kite-length" about ready to have a new kite added at the ground end, and almost the same amount of curve leading off-panel to the next (previously attached) kite, unseen. There are flat items (presumably kites), spools (one being the current one being fed out) and boxes (assumed to contain more kite material and/or spools behind and around the two small figures.]

[A much larger panel with the same ground details but a wider view. Above the ascending line of kites there is now a second, horizontal line of kites, dangling furves of connecting chord, leading from off-panel left to off-panel right.]

Cueball: Uhh...

[Some kites, spools and boxes are around the two figures, now seen again in close-up.]

Cueball: ...Did it blow in a circle?

Megan: I don't know. Lemme look at a map of where the jet stream goes.

Cueball: Hey, do you hear sirens?

[A CNN logo is at the upper right of the panel. Megan stands at a lectern, with Cueball on one side and Ponytail, holding a briefcase, on the other. An illegible news ticker is shown below them, along with more illegible text on either side of the panel, just above the news ticker.]

[A banner with white text on a black background:]

Breaking: Kite Incident Duo Speaks

Megan: On the advice of our lawyer, we would like to apologize for the events that shut down global air travel last week...

  Add comment        Create topic (use sparingly)       Refresh 

Discussion

First post! 162.195.34.112 21:47, 28 July 2025 (UTC)

hey :) i wrote the current transcription and it definitely doesn't look perfect so if anyone has any feedback on how to improve i'd rly appreciate it (also like to add that i think this is probably my fav title text in all of xkcd) stevethenoob 22:16, 28 July 2025 (UTC)

The last frame says it shut down global air travel. I think it's implied that the line of kites circled the world. 2001:8003:6490:9700:94EE:E801:7399:7FD9 22:45, 28 July 2025 (UTC)

I think, at worst, it'd be hemispherical travel that's disrupted (wouldn't cross over between northern and southern Hadley Cells at all), though of course that would still affect air travel in which at least one end originated in the northern hemisphere (Sydney to Buenos Aires, etc, should probably be safe to fly) and there'd be an abundance of caution anyway, at least until the rather one-dimensional threat is properly identified (and the nature/origin of its deployment).

Also, I think a plane could probably strike an actual kite or two without too much problems (much less substantial than a bird-strike, and they're designed to shrug off at least the smaller birds), and I can't see the kite-line being an issue, as even a high-strength fishing line is probably vulnerable to the mechanical concentration of stresses.

Though I'm surprised it has the tensile strength to lead around the world, prior to any contact with a plane, as all it takes is for a slight wind-differential and the force of numerous down-wind kites could end up creating a tension against the more steady release from the ground and the relative back-pull from all kites that are upwind of that point), either snapping the line or parting a knot between two adjacent spool-ends of line. You can use a fishing line well beyond its design limit by smooth tugging action/responding properly to the pull of the hooked fish at the other end, but localised jerks and jinks will be hard to avoid across thousands of miles of polymer chord flexing and reacting to the way each of its periodically-attached kits want to move at their respective locations along the 'master string(s)'. 92.23.2.228 00:18, 29 July 2025 (UTC)

Interrupting those 'inter-hemisphere' flights would likely have knock-on effects on other flights in the otherwise non-affected hemisphere, due to planes and crews being in the wrong place, disruption to flight slots, etc. - see for example how the Iceland volcano caused disruption right across Europe and beyond, even for flights in areas nowhere near the dust cloud. 82.13.184.33 08:50, 29 July 2025 (UTC)

It would not actively shut down southern-hemisphere traffic, though, just disrupt it. Ironically, could even mean those flights that fly have fewer take-off and mid-air delays, not needing to queue/enter holding patterns quite so much at the now much less busy airports - though that'd be trivial and just not eating into acceptable time-buffers that every flight should have.

And I can't envisage a London to Sydney (now rested, first-shift) flight crew and plans being the only ones that are able to now go from Sydney to Wellington as a new flight onwards, if that was somehow factored in. They could be as easily replaced by the Sydney to Tokyo ones who now can't set off, etc. (Or some shuffling between where pilots and plans actually are, as there'll be plenty of spares in Johannasburg, Rio, etc, otherwise sitting idle and unable to get 'north', even as others are actively held back from reaching 'south'.

It was the more localised effect of the Icelandic volcano (or occasions like when Russia shot down the airliner over Ukraine) which meant that the 'fringe' of effected area to be avoided impinged into routes further away, and required flights that would merely skirt the area to consider their options, but the fringe of a whole hemisphere (which doesn't affect south-only specialist airlines) is arguably less significant, by proportion. Iceland was particularly disproportionate because the significant transatlantic travel tends to take paths up through the downstream ash-cloud, even between the extreme southern Europe and its equivalent US latitudes. Great circle (short) segments don't, however, cross the equator, but aftually bend away from it, so two south-of-equator endpoints have a flight path that's safer.

If an individual airline is running a (say) (North->)South1->South2->North(->South1) triangular service, normally, then it might have a problem if it doesn't run a S1->N->S2 counter-circuit with another plane (that also isn't 'trapped' North at the wrong moment), but can at least S1<->S2 until things clear up. And arrangements with other airlines (with opposingly 'south-trapped' resources) can probably paper over mutual gaps in coverage, if there's enough common goodwill for the duration. 82.132.237.17 09:31, 29 July 2025 (UTC)

Well for that matter, the Iceland volcano didn't totally shut down European air travel, but people still spoke about it in those terms. So I guess it depends what you mean by 'shut down' - whether you take a literal interpretation of 'there is none of it at all', or a somewhat looser common parlance interpretation of 'severely disrupt'. Also possibly depends on your interpretation of 'global air travel' - whether you take that to mean 'any air travel anywhere in the world', or 'air travel on a global scale' (i.e. long-distance international flights). 82.13.184.33 08:13, 30 July 2025 (UTC)

This is not the first time that Megan has expressed an interest in flying kites, nor the second. It's also not the first time that Cueball has taken kite flying way too far. 2600:4040:5432:F700:80B6:B228:2EDB:6FC4 00:46, 29 July 2025 (UTC)

I love this one, for me it is very much early xkcd spirit in there, with just people out and exploring, having fun, trying things... I don't think I can really describe, anyone feels the same? --Lupo (talk) 04:40, 29 July 2025 (UTC)

I agree, this very much feels like it could've been somewhere between .com/800 to .com/1200 and one of the better ones at that stevethenoob 10:59, 29 July 2025 (UTC)

Years ago someone told me that he had met Randall through their mutual interest in kites. 47.34.153.128 (talk) 07:50, 29 July 2025 (please sign your comments with ~~~~)

Me and my Dad had something similar happen when I was 15. He built me a big (8 foot tall) box kite and we went to fly it in a field beside our house. Problem was that on the other side of the field was the city's airport. All of a sudden a truck with flashing lights came charging through the field to where we were. A guy got out, looked up at the kite, looked at us, looked up at the kite again and said "Ummm.. you're going to have to fly that somewhere else - we're picking you up on radar." This was in the 90's before drones were a thing. I can imagine the panic when an unedentified blip shows up on radar with no transponder. That kite was lots of fun (though a little dangerous in high winds) it had a harness to hold it and it dragged me across a field once before my Dad grabbed me. Maybe I should make a quick release for it. 64.203.66.182 (talk) 14:30, 29 July 2025 (please sign your comments with ~~~~)

My cousin and I did this in the '80s with the same kind of kite. Kept tying on 200 ft spools of kite string until we went through 20 and couldn't see the kite any more. Tied it off to a fence and left it overnight. Tracked the string the next day (which never touched the ground) to the roof of a house a half mile away. How I wish we'd thought of adding more kites! -- BrickOfReality (talk) 15:19, 29 July 2025 (UTC) (please sign your comments with ~~~~)

We need someone who knows Calculus to come in and model the dangling line as the catenary equation. I know just enough to know how much I dont know 😭 199.241.130.234 (talk) 15:44, 29 July 2025 (UTC) (please sign your comments with ~~~~)

The weight of the string will be properly lifted by each kite. However, the horizontal tension will get higher and higher, as each kite needs lateral tension in order to resist the wind, and all the tensions will add up. This will decrease the depth of the catenary curve, but you will also need to increase the strength (and thus weight) of the string after not too many kites are added. -- Dtgriscom (talk) 16:15, 29 July 2025 (UTC)

if the kite is that strong, megan should NOT be holding the string with her bare hands. there's a reason modern kites have specially designed handles. (source: flew a big kite this summer, briefly tried to hold the string and Immediately regretted it) 73.190.140.221 16:40, 1 August 2025 (UTC)

The line is being fed via a ground-peg, perhaps only guided/released by Megan, who could be wearing suitable gloves/palm-protection that allows for enough friction without damaging either hands or 'string'. Given the open-ended (i.e. continually extended, by splicing in new spools) feed of line, I'm not sure there's a particularly better way than this. But I'm not anything more than an amateur kite-flier, so maybe I'm unaware of a better system (e.g. using proper friction-handling equipment on the spool side of the ground-anchor, feeding it and whatever passes it is now untouched all the way up to the kite(s)...) 92.23.2.228 19:51, 1 August 2025 (UTC)
        Add comment