explain xkcd - User contributions [en]

Talk:3199: Early Arthropods

2026-01-27T04:39:07Z

Cphoenix: Tweaking my own comment

Edit conflict on the transcript. Whoops! —megan [[user talk:megan|talk]] [[special:contribs/megan|contribs]] 00:45, 27 January 2026 (UTC)

there is a typo in title text, i wonder if it will be corrected [[Special:Contributions/2A02:A31A:E2CD:5300:5450:CAAA:3F64:5EE5|2A02:A31A:E2CD:5300:5450:CAAA:3F64:5EE5]] 01:45, 27 January 2026 (UTC)

First - [[Special:Contributions/45.178.1.151|45.178.1.151]] 01:08, 28 January 2025 (UTC)

Early Cnidarians:

"I'm going to be the biggest quilt-shaped bag of cells I can be!"

"I'm going to evolve special stinging cells!"

"I'm going to use [https://jetpress.org/v20/phoenix.htm epigenetics to lock my cells into lifelong somatic roles], and then they can use synaptic learning in their newly stable neural nets to develop novel behaviors by learning from their environment, and eventually one of my descendants will invent machines that they can publish webcomics on!" [[User:Cphoenix|Cphoenix]] ([[User talk:Cphoenix|talk]]) 04:37, 27 January 2026 (UTC)

Talk:3199: Early Arthropods

2026-01-27T04:37:06Z

Cphoenix: Comment on early Cnidarians paralleling this comic's structure, with a reference to my published paper about a possible trigger for the Cambrian Explosion.

Edit conflict on the transcript. Whoops! —megan [[user talk:megan|talk]] [[special:contribs/megan|contribs]] 00:45, 27 January 2026 (UTC)

there is a typo in title text, i wonder if it will be corrected [[Special:Contributions/2A02:A31A:E2CD:5300:5450:CAAA:3F64:5EE5|2A02:A31A:E2CD:5300:5450:CAAA:3F64:5EE5]] 01:45, 27 January 2026 (UTC)

First - [[Special:Contributions/45.178.1.151|45.178.1.151]] 01:08, 28 January 2025 (UTC)

Early Cnidarians:

"I'm going to be the biggest quilt-shaped bag of cells I can be!"

"I'm going to evolve special stinging cells!"

"I'm going to use [https://jetpress.org/v20/phoenix.htm epigenetics to lock my cells into lifelong somatic roles], and then they can use synaptic learning in their newly stable neural nets to develop lifelong responses from their environment, and eventually one of my descendants will invent machines that they can publish webcomics on!" [[User:Cphoenix|Cphoenix]] ([[User talk:Cphoenix|talk]]) 04:37, 27 January 2026 (UTC)

Talk:3093: Drafting

2025-05-24T06:43:10Z

Cphoenix: Hot staging of Starship will use Starship's thrust to increase Super Heavy's efficiency - yes, really.

The efficiency loss is presuamably because the exhaust from the lead rocket is pushing back on the following rocket. It's also really hot, so the follower may be destroyed. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 15:27, 23 May 2025 (UTC)

Anyone else getting lots of "site is experiencing difficulties" errors [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 15:28, 23 May 2025 (UTC)
:Yes. It must be drafting behind another, more powerful rocket-themed web page and was experiencing some of that "99% inefficiency." [[Special:Contributions/172.68.26.136|172.68.26.136]] 15:56, 23 May 2025 (UTC)
: " getting lots of "site is experiencing difficulties" errors " Yes. --[[User:PRR|PRR]] ([[User talk:PRR|talk]]) 16:22, 23 May 2025 (UTC)
:Yes. From the experience of another forum I'm in, it's probably a sudden uptick on (possibly AI-feeding?) site-scraping. On that site, the number of viewers suddenly increased from a few hundred people online, maximum, at any given time, to tens of thousands. The owner of the site put an additional "are you human" check in the way (after about a week of it), and it fell back to less than a hundred simultaneous connections (not that far off the actual observable user-traffic, with a couple of handfuls of Guest lurkers at any given time, rather than the pre-slowdown peaks of three or four times the provably genuine users).
:That site didn't have Cloudflare, unlike here, and didn't use that as a solution. I would have ''hoped'' that this would have mitigated it here, though. Possibly, however, things could have already been hundreds of times worse without it as it is, hard to know for sure.
:And though my reasoning of the cause is just a guess, I'm sure others have noticed that the amount of 503/Connection Issue responses we're getting has substantially reduced the spam-level numbers of "goes nowhere, does nothing" new accounts that this site tends to get (its other anti-spam protections having long since prevented most of those from doing anything, while still seemingly allowing genuine users to interact). Hard to fully qualify that as a positive, but I suspect that genuinely driven 'honest editors' are more likely to persevere and get past the current bottlenecks, so it might (in certain, rather limited, terms) ''improve'' the editing experience. (The other site started to be ''really'' hammered (to then prompt calls for its subsequent changes) on 11/May, which seems to me to coincide very closely with the drop in new spam-style account names on here, which seems to corroborate it being the same global issue causing both sites problems.)
:Not that I wouldn't appreciate less of the 503s/etc. It definitely is a direct annoyance. Which I can't see being solved any time soon (if Cloudflare doesn't blanket add to its proxying protections, itself). [[Special:Contributions/172.68.229.49|172.68.229.49]] 16:34, 23 May 2025 (UTC)
::Also here. Had to reload the page three times before I could begin writing. And will likely have to reload or try again several times before this is posted --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 19:06, 23 May 2025 (UTC)

Added notes on difference between friction and expellant propulsion [[Special:Contributions/172.69.212.151|172.69.212.151]] 16:14, 23 May 2025 (UTC)

Just a comment about drafting and cycle-sport. It might be used in peletons and certain velodrome events (i.e. not "pursuit" ones). But in my own part of the sport, time-trialling, it is actually ''not allowed'' (excepting in team time-trials), as competitors that have just been passed by a faster rider are not supposed to hang on (figuratively, of course) to their wheel. Nor should you try to catch your minute-man just so that you can stick behind them. Also, the rules on the amount of traffic allowed on the roads during an event, as well as being a direct safety aspect on the busiest of roads, are meant to remove any excessive advantage from passing traffic (especially lorries) pushing/pulling the competitors along. This doesn't mean that the occasional ride won't get some assistance. A fast tractor may be too slow for a fast rider to stay behind, who would really need to pass it when safe to do so, but could be going just fast enough for a slower one to benefit (but at the risk of being spotted doing so and the issue addressed appropriately). But competitor-on-competitor co-pacing (or accompanied riding of any other unofficial kind) is ''definitely a no-no''. [[Special:Contributions/172.68.229.49|172.68.229.49]] 16:34, 23 May 2025 (UTC)

This comic made me think of this video: https://www.youtube.com/shorts/yuMcAS_wRRQ [[Special:Contributions/172.69.212.145|172.69.212.145]] 17:45, 23 May 2025 (UTC)

The exhaust of the lead rocket might increase the density of the gas around the following rocket, thus affecting the efficiency of the following rocket's engine. (Giving the effect of being at a lower altitude if in atmospheric flight.) Rockets generally are less efficient in higher density atmosphere, and are designed for a particular density.
If the following rocket was close enough, it might alter the efficiency of the lead rocket by increasing density near the lead rockets engine, or by providing something similar to ground effect for the lead rocket. (The extent of such effects would also depend on any atmosphere.) [[Special:Contributions/108.162.245.19|108.162.245.19]] 19:12, 23 May 2025 (UTC)

Since rockets often travel at supersonic speeds, it seems like the costs and benefits of drafting might be altered, compared to land vehicles drafting at subsonic speeds. (Would both rockets have shock waves in front, would the shockwave from the trailing rocket interact with the first rocket, ...) Seems like it would be worth mentioning, but I couldn't find much about supersonic slipstreaming. Since I am not a rocket scientist, I wouldn't hazard a guess what might happen. [[Special:Contributions/162.158.41.115|162.158.41.115]] 19:35, 23 May 2025 (UTC)

I am aware that bicycle races exist and except for occasional articles about cheating (the most interesting method was extracting one's red blood cells, storing up quite a lot, and putting them back in right before the race) don't care. Geese. Drafting is why I see a vee of geese where the leader peels back and becomes a follower accompanied by a bunch of geese that are just a flock. I think that fighter planes can use drafting. I've noticed the effect when a semi blows past me.[[Special:Contributions/172.71.222.202|172.71.222.202]] 06:26, 24 May 2025 (UTC)

Ironically, Elon Musk has just announced that when the Starship hot-stages from the Super Heavy (meaning one rocket closely following another, both with engines firing, much like the picture), some of the vent ports at the top of the Super Heavy will be blocked so that the thrust from Starship will come out directionally and push the Super Heavy in a predictable direction... thus increasing its efficiency! [[User:Cphoenix|Cphoenix]] ([[User talk:Cphoenix|talk]]) 06:43, 24 May 2025 (UTC)

Talk:3093: Drafting

2025-05-24T06:42:37Z

Cphoenix: Hot staging of Starship will use Starship's thrust to increase Super Heavy's efficiency - yes, really.

Talk:3087: Pascal's Law

2025-05-10T01:01:49Z

Cphoenix: Counterexample: an oversimplified law of physics that leads to a counterfactual conclusion by similar reasoning

I remember learning about this and thinking it was intuitive, but I didn't really think of these consequences. Maybe everybody is making powerful lifting machines for lifting cars and houses with your bare hands, rather than explaining the article, that there isn't one yet. Pascal's law basically says that if you make one end of a container of fluid X times larger, then any force exerted on the small end is multiplied by X on the large end, so you can make it near-infinite by making the small end very small. But you'll need a little more machinery added (like a gear system) if you want the distance actually moved to be higher. Actually I think that might undo the gains in force entirely. That might be how it happens, it might swap distance for force so the same work is performed.

Hey, remember that comic where Randal challenged people to fold a paper too small? This hand-makeable device could get farther on that!
[[Special:Contributions/172.70.111.110|172.70.111.110]] 21:46, 9 May 2025 (UTC)
: yes, that's how it works; the total work is constant and the hydraulic system is converting a small force over a long distance to a large force over a small distance. if you additionally want the force to be over a larger distance, you need to put more energy into the system or else you could push this machine with its own output and get free energy from nothing. really though hydraulics are just smoother, backlashless, equivalents to a gear train in the first place so you generally wouldnt need to use both. - [[User:Vaedez|Vaedez]] ([[User talk:Vaedez|talk]]) 23:37, 9 May 2025 (UTC)

As someone old enough to remember the [https://en.m.wikipedia.org/wiki/Slashdot_effect slashdot effect], I wonder if XKCD comics generate a similar effect on search engines. Though I doubt they would buckle under the weight these days. [[Special:Contributions/172.69.60.148|172.69.60.148]] 22:00, 9 May 2025 (UTC)

To whoever wrote the initial transcript, remember that we don't include the title text. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 22:06, 9 May 2025 (UTC)

I have to wonder whether he has the same disbelief of, say, levers... which allow one to move the Earth. [[User:Jordan Brown|Jordan Brown]] ([[User talk:Jordan Brown|talk]]) 23:34, 9 May 2025 (UTC)

Although some laws of physics are absolute and lead to extreme consequences, others are taught in a simplified form that can lead to wrong conclusions. For example, "Light and heavy objects fall at the same rate" can be used to prove that objects fall at the same rate on the Earth and the Moon - which is far from correct. If the Moon were somehow dropped onto the Earth, it would fall at a certain rate. The Earth dropped on the Moon would necessarily fall at the same rate. So if the Moon falling on the Earth fell at the same rate as a bowling ball, then the bowling ball would have to fall at the same rate on the Moon. When I read Heinlein's _The Rolling Stones_ as a pre-teen, where he describes things falling slower on the Moon, I applied this reasoning and concluded that Heinlein must have made a mistake. The solution to this paradox is that something as big as the Moon will not only accelerate toward the Earth, it will significantly accelerate the Earth toward it, so the Moon does not actually fall at the same rate as a bowling ball. [[User:Cphoenix|Cphoenix]] ([[User talk:Cphoenix|talk]]) 01:01, 10 May 2025 (UTC)

3039: Human Altitude

2025-01-18T01:58:06Z

Cphoenix: Forgot to change the comment when I edited a few seconds ago

{{comic
| number = 3039
| date = January 17, 2025
| title = Human Altitude
| image = human_altitude_2x.png
| imagesize = 508x495px
| noexpand = true
| titletext = I wonder what surviving human held the record before balloons (excluding edge cases like jumping gaps on a mountain bridge). Probably it was someone falling from a cliff into snow or water, but maybe it involved something weird like a gunpowder explosion or volcano.
}}

==Explanation==
{{incomplete|Created by a TORNADO - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
The comic purports to show the altitudes of humans over time, starting from a little after 1700. It uses a logarithmic vertical scale in order to indicate the finer details of 'low level' altitudes, yet fit the highest achievements onto the page. The measurements do not count altitude ''due'' to the ground beneath them, so a resident of {{w|Tibet}} or the {{w|Andes|high Peruvian Andes}} (for example) does not normally gain any particular advantage.

Prior to 1783, the first confirmed ascent of a human in a balloon, the line's high-points are indicated to be due to "various falls", i.e. a person who ''was'' on the top of a particularly high building/cliff/tree suddenly finding themselves (for an instant or two, at least) the person 'lucky' enough to be considered the furthest above the ground (it is at times like this that living at a higher absolute altitude ''might'' grant an 'advantage' to the individual who suddenly discovers their previously high standing-spot to no longer be as reliable as they thought). It also suggests that "catapult accidents" (indicated as "hilarious") may also contribute to the (momentary) gain in altitude. The limit to this period's ability to exist at altitude appears to be around 100 metres, which is perhaps mostly what a particular precipitous (and precarious) cliff-top might contribute to the situation.

Once {{w|balloon}} flights start, heights of up to 10km are attained. And though there were some {{w|List of ballooning accidents|dangers}} from this, as early aeronauts discovered, it might at least now be presumed that some of these peaks were attained by individuals who had previously marked a prior instantaneous altitude on the graph.

Shortly after the 1900s, {{w|airplanes}} dominate the graph. And the rise in utility of passenger aircraft (before World War 2; but especially afterwards, following a period where regular and extended high-altitude flight has been experienced by bomber pilots of various nations) ensures not only that there are people attaining greater and greater altitudes, but also that there are also always ''other'' people in the air, ensuring that the lesser 'maximum altitude' periods still have people a significant number of kilometres in the air.

Interestingly, the lower-limit, all the way up to the invention of the airplane, seems to stay at about two metres (around 1881, the lowest marked position seems to be only slightly above 1 metre), which might represent the possibility of there always being at least ''someone'' climbing up a ladder and/or jumping off of a hay-cart.

Once {{w|spaceflight}} becomes a thing (interestingly, marked around the late 1960s, though it actually started in April 1961), that greatly increases the upper spikes for the (implied) duration of the {{w|Orbital spaceflight|orbital flights}}.

The {{w|Apollo Program}} is then indicated by both label and a notable spike as (between {{w|Apollo 8}} in December 1968 and {{w|Apollo 17}} in December 1972), men from Earth were sent around the Moon and attained altitudes 'above the Earth' of approximately 400,000km in the process.

Since the end of the original Moon landings, the upper spikes settled down quite significantly back to 'only' generally low orbital distances, but he very latest era, marked "Space Station", seems to coincide with the current continuous inhabitation of space, which officially started in November 2000. Since that date, there has ''always'' been someone at approximately 400km altitude (give or take changes in the orbit, and of the terrain below), with occasionally some yet higher person(s) on certain missions (e.g. servicing the {{w|Hubble Space Telescope}}, May 2009 at 515km). The graph does not ''seem'' to show the blip created by Polaris Dawn's 1,400 km 'new record' of September 2024, but this may be ''just'' off the right-hand edge of the graph.

Though the historical validity is sometimes argued, it is interesting to note that (as early as the 6th century CE), experiments with man-flying kites may have produced (semi-)brief spikes in the altitude record for the time. Gliders of the later era (starting roughly at the start of the 1800s) were probably eclipsed by the indicated balloons, but may have produced ''some'' of the spikes seen (above 10 metres but well below the multi-kilometre peaks), as occasional departures off the tops of hills were accomplished without quite so much ill-fortune, or at least without being ''entirely'' unintentional.

Tornadoes are another possible cause of high-altitude humans. There are multiple credible stories, [https://www.youtube.com/watch?v=pEPf6K-Y7GA| like this one], of people being lifted off the ground and surviving. In theory, they could have been lifted well over 100 meters and still survived.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

{{comic discussion}}

3039: Human Altitude

2025-01-18T01:55:43Z

Cphoenix: Mention of tornadoes as a potential cause of human altitude.

{{comic
| number = 3039
| date = January 17, 2025
| title = Human Altitude
| image = human_altitude_2x.png
| imagesize = 508x495px
| noexpand = true
| titletext = I wonder what surviving human held the record before balloons (excluding edge cases like jumping gaps on a mountain bridge). Probably it was someone falling from a cliff into snow or water, but maybe it involved something weird like a gunpowder explosion or volcano.
}}

==Explanation==
{{incomplete|Created by a GUNPOWDER CATAPULT ACCIDENT - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
The comic purports to show the altitudes of humans over time, starting from a little after 1700. It uses a logarithmic vertical scale in order to indicate the finer details of 'low level' altitudes, yet fit the highest achievements onto the page. The measurements do not count altitude ''due'' to the ground beneath them, so a resident of {{w|Tibet}} or the {{w|Andes|high Peruvian Andes}} (for example) does not normally gain any particular advantage.

Prior to 1783, the first confirmed ascent of a human in a balloon, the line's high-points are indicated to be due to "various falls", i.e. a person who ''was'' on the top of a particularly high building/cliff/tree suddenly finding themselves (for an instant or two, at least) the person 'lucky' enough to be considered the furthest above the ground (it is at times like this that living at a higher absolute altitude ''might'' grant an 'advantage' to the individual who suddenly discovers their previously high standing-spot to no longer be as reliable as they thought). It also suggests that "catapult accidents" (indicated as "hilarious") may also contribute to the (momentary) gain in altitude. The limit to this period's ability to exist at altitude appears to be around 100 metres, which is perhaps mostly what a particular precipitous (and precarious) cliff-top might contribute to the situation.

Once {{w|balloon}} flights start, heights of up to 10km are attained. And though there were some {{w|List of ballooning accidents|dangers}} from this, as early aeronauts discovered, it might at least now be presumed that some of these peaks were attained by individuals who had previously marked a prior instantaneous altitude on the graph.

Shortly after the 1900s, {{w|airplanes}} dominate the graph. And the rise in utility of passenger aircraft (before World War 2; but especially afterwards, following a period where regular and extended high-altitude flight has been experienced by bomber pilots of various nations) ensures not only that there are people attaining greater and greater altitudes, but also that there are also always ''other'' people in the air, ensuring that the lesser 'maximum altitude' periods still have people a significant number of kilometres in the air.

Interestingly, the lower-limit, all the way up to the invention of the airplane, seems to stay at about two metres (around 1881, the lowest marked position seems to be only slightly above 1 metre), which might represent the possibility of there always being at least ''someone'' climbing up a ladder and/or jumping off of a hay-cart.

Once {{w|spaceflight}} becomes a thing (interestingly, marked around the late 1960s, though it actually started in April 1961), that greatly increases the upper spikes for the (implied) duration of the {{w|Orbital spaceflight|orbital flights}}.

The {{w|Apollo Program}} is then indicated by both label and a notable spike as (between {{w|Apollo 8}} in December 1968 and {{w|Apollo 17}} in December 1972), men from Earth were sent around the Moon and attained altitudes 'above the Earth' of approximately 400,000km in the process.

Since the end of the original Moon landings, the upper spikes settled down quite significantly back to 'only' generally low orbital distances, but he very latest era, marked "Space Station", seems to coincide with the current continuous inhabitation of space, which officially started in November 2000. Since that date, there has ''always'' been someone at approximately 400km altitude (give or take changes in the orbit, and of the terrain below), with occasionally some yet higher person(s) on certain missions (e.g. servicing the {{w|Hubble Space Telescope}}, May 2009 at 515km). The graph does not ''seem'' to show the blip created by Polaris Dawn's 1,400 km 'new record' of September 2024, but this may be ''just'' off the right-hand edge of the graph.

Though the historical validity is sometimes argued, it is interesting to note that (as early as the 6th century CE), experiments with man-flying kites may have produced (semi-)brief spikes in the altitude record for the time. Gliders of the later era (starting roughly at the start of the 1800s) were probably eclipsed by the indicated balloons, but may have produced ''some'' of the spikes seen (above 10 metres but well below the multi-kilometre peaks), as occasional departures off the tops of hills were accomplished without quite so much ill-fortune, or at least without being ''entirely'' unintentional.

Tornadoes are another possible cause of high-altitude humans. There are multiple credible stories, [https://www.youtube.com/watch?v=pEPf6K-Y7GA| like this one], of people being lifted off the ground and surviving. In theory, they could have been lifted well over 100 meters and still survived.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

{{comic discussion}}

3013: Kedging Cannon

2024-11-20T07:30:25Z

Cphoenix: Mention of chain boats as a real-life example of extended kedging.

{{comic
| number = 3013
| date = November 18, 2024
| title = Kedging Cannon
| image = kedging_cannon_2x.png
| imagesize = 740x259px
| noexpand = true
| titletext = The real key was inventing the windmill-powered winch.
}}

==Explanation==
{{incomplete|Created by a HEADCANNON. Do NOT delete this tag too soon.}}

Prior to the invention of powered ships, oceangoing vessels moved primarily by means of wind power, which meant that they were restricted by the direction and power of the winds. If a sailing vessel needs to travel upwind (against the wind), they typically make use of a technique called {{w|Tacking_(sailing)|tacking}} (or "tacking against the wind") which involves zigzagging across the wind's direction. This method is significantly slower and more difficult than traveling downwind, but it makes upwind navigation possible.

This comic portrays a fictional scenario where a ship's captain, apparently unfamiliar with tacking, has developed an alternative method based on {{w|kedging}} (also known as warping).

The basics of kedging are not dissimilar to the comic: a boat affixes a rope or chain to an anchor point (such as a literal anchor) and winches itself closer. Traditionally kedging involves deploying an anchor from the vessel, either manually or via a smaller boat, and then {{w|winch|winching}} the ship toward the anchor point using ropes or chains. This is a real method, but is clearly very slow and labor intensive. Generally kedging is only effective in shallow waters and employed when tacking is not an option, as for example in harbors or narrow channels where space is tightly constricted. The captain in this strip appears to be using it for long-distance travel, which would be highly impractical. What's more, he deploys his anchor with a cannon, wasting large amount of gunpowder (although with the setup as depicted, wasting gunpowder would be the least of a ship's concerns, as firing something the weight of an anchor any meaningful distance would require so much force it would outright rupture just about any age of sail artillerypiece), all while a confused Cueball looks on wondering why the Captain isn't trying to use tacking instead.

This approach to transportation has been used in war when the wind halts, with ongoing gunfire. This may be where the concept of using a cannon to send the anchor came from, as such a situation may involve an excess supply of gunpowder.

Where the water is too deep for the anchor to reach the bottom, a so-called {{w|sea anchor}} could theoretically be used, but would be even less practical. Kedging with a sea anchor would effectively be a very slow and inefficient version of rowing, which is alternative (albeit labor-intensive) method to travel against the wind.

The title text indicates that the captain's system has evolved to incorporate a windmill mechanism that harnesses wind power to draw in the kedging rope, windmills are much more intuitive to use for kinetic energy, as the concepts behind the airfoil are very commonly misunderstood (see [[803: Airfoil]]). The comment brings to mind the comparison of the energy efficiency of a windmill pulling in a rope vs normal tacking, which different audiences will have different intuitions about, and as such the joke will land differently for different people. Likely this is a ridiculously inefficient {{w|Rube Goldberg machine|Rube-Goldberg-like}} solution to wind propulsion, if tacking has been discovered, and an ingenious energy saver (if heavy and expensive) if not. An analysis of the efficiency is below.

==In real life==
On some rivers, {{w|Chain_boat|chain boats}} were used for about a century. A chain would be laid the length of the river, and the boat used a winch to pull itself along the chain. Rudders and booms could replace the chain in the center of the river even around bends. It turned out to be very difficult to drive the chain with enough force - several techniques were attempted.

{{cot|Speed and economic analysis of dual wind-winched kedging cannons compared to tacking}}
A dual-anchor kedging cannon system for sailing upwind, consisting of:
* Two kedging cannons firing 16 kg anchors
* 6-meter diameter windmill powering winch system
* Dual-winch setup for continuous operation
* Operating in 15 knot headwind conditions

Vessel specifications:
* Length: 30 feet (9.1 meters)
* Displacement: 10,000 lbs (4536 kg)
* Sail area: 600 sq ft (55.7 m²)
* Wetted surface: 40 m²
* Frontal area: 8 m²

;Wind power generation
Available wind power is given by:
''P'' = ½''ρAv''³''η''
where:
* ''ρ'' = 1.225 kg/m³ (air density)
* ''A'' = ''π''(''D''/2)² = 28.3 m² (windmill area)
* ''v'' = 7.72 m/s (wind speed)
* ''η'' = 0.245 (combined efficiency)

This yields 1.95 kW of usable power.

;Drag forces
Total drag combines water and air resistance:
''F''drag = ''F''water + ''F''wind
where:
* ''F''water = ½''ρ''w''C''d''A''w''v''²
* ''F''wind = ½''ρ''a''C''a''A''f''v''²

Using:
* Water density (''ρ''w) = 1025 kg/m³
* Hull drag coefficient (''C''d) = 0.04
* Wetted area (''A''w) = 40 m²
* Air density (''ρ''a) = 1.225 kg/m³
* Air drag coefficient (''C''a) = 0.8
* Frontal area (''A''f) = 8 m²

Total drag force = 1053.4 N

;Anchor ballistics
For 300 m range with 45° launch angle:
* Required velocity = 54.7 m/s
* Launch energy = 23.7 kJ
* Black powder energy per shot = 680.4 kJ
* Launch efficiency = 3.5%

;System performance
* Winch speed = 3.60 knots
* Cycle time = 194.7 seconds
* Effective speed = 3.04 knots
* Compared to tacking speed = 4.95 knots
* Speed ratio (kedging/tacking) = 0.61

;Economic analysis
* Shots needed per nautical mile: 6.1
* Black powder cost per shot: $10 (0.5 lbs @ $20/lb)
* Cost per nautical mile: $60.76
* Powder consumption: 9.2 lbs/hour
* Operating cost: $184.90/hour

Example 100 nmi journey:
* Total powder cost: $6,076.12
* Journey time: 32.9 hours

;Conclusion
The dual-anchor kedging cannon system is both slower and significantly more expensive than traditional tacking:

Speed disadvantage:
* Achieves only 61% of tacking speed
* 100 nmi journey takes 32.9 hours vs 20.2 hours tacking

Economic disadvantage:
* High powder costs ($60.76 per nautical mile)
* Requires significant powder storage (303 lbs for 100 nmi journey)
* Additional wear and tear on mechanical systems

Key limiting factors:
* Limited wind power available (1.95 kW from 6 m windmill)
* High drag forces (1053.4 N total)
* Poor ballistic efficiency (3.5% of powder energy converts to useful launch)
* Long cycle times due to realistic winching speeds

The system could potentially be improved by:
* Larger windmill (though practical size limits on boats)
* More aerodynamic anchor design
* More efficient powder-to-launch energy conversion
* Reduced transfer time between anchors

Therefore, given both the energy constraints and economic factors, traditional tacking remains far more practical for upwind progress. The key insight is that while the kedging cannon seems to "cheat" the wind by going straight upwind, it actually requires converting wind energy to mechanical work less efficiently than a well-designed sail plan, while also consuming expensive gunpowder. The indirect path of tacking makes better use of the available wind force with no consumable costs.
{{cob}}

==Transcript==
:[A two-masted sailing ship with its sails up is floating on a calm sea with tiny waves. Two tiny figures can be seen at the ship's bow. One of them is speaking. In the next panel it becomes clear this is the captain.]
:Captain: I hope someday someone invents a way to sail upwind.
:Captain: Using the kedging cannon just wastes so much gunpowder.

:[Close-up on the deck of the ship, showing two persons behind the taffrail. Cueball is standing behind the ship's captain and talking to him. The captain is wearing a black bicorne navy hat and aiming a cannon containing an anchor forward. Chains are draped from the cannon.]
:Cueball: The '''''what?'''''
:Cueball: Wait, do you not know how to sail upwind? Is that why your ship takes forever to--
:Captain: Stand by...'''''Fire!'''''

:[Distant shot showing the anchor and its chain being launched out in front of the ship, towards the right of the panel. Cueball and the Captain can still be seen behind the cannon. The cannon has exhaust fumes coming out in front and the sound it makes is indicated:]
:Cannon: ''Boom''

:[Same setting but the anchor is now under water and the chain has become taut as the ship is dragged forward to the right. Movement lines behind the ship indicated its progress and it is also further into the frame than the previous panel. The movement is caused by pulling the chain back in on the ship. This produces a series of sounds:]
:Dragging chain: ''Click click click''

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Characters with hats]]