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| Aerospace Flowchart |
 Title text: Someday, we will find the problem that goes with this solution. |
Explanation
This comic is a section of a flowchart satirically depicting the work-flow process for aerospace engineers. The portion displayed implies that the first step for every problem is to consider whether the problem could be solved with "giant airships". It also implies that the answer is always 'no', but that this will always be considered before moving on to other solutions.
Airships refer to a type of aircraft that operate by buoyancy. The bulk of such aircraft consists of a large envelope filled with a lifting gas which is lighter than air (generally hydrogen or helium). These vessels were the only practical method of human flight for over a century, but were rendered obsolete by the invention of the airplane and other systems of powered flight. Airships are, by necessity, much larger than airplanes, due to the huge volume of lifting gas required. Consequently, they tend to be far slower and less maneuverable than airplanes, while being more delicate and vulnerable to the weather. Hydrogen, which was once the primary lifting gas, fell out of favor due to its high flammability, while helium is expensive in the kinds of quantities needed. They also require balancing of weight and buoyancy, which complicates ascent and descent, as well as any change in payload. All these factors have relegated airships to rare, niche uses in modern times.
Despite all these disadvantages, the idea of airships continues to catch the imagination of aerospace enthusiasts. The central joke of the strip is that even professionals in the field tend to dream of resurrecting the technology, but can never find a practical justification to do so. There are potential advantages to airships: they can potentially travel with much less power than other aircraft (albeit more slowly). They can stay aloft indefinitely, even hovering in place, with minimal energy use, and produce far less sound and air disturbance than powered aircraft. In theory, they can take off and land vertically with little infrastructure on the ground (in practice, though, ground handling tends to be hugely complicated by the weather). None of these advantages have proven powerful enough to overcome the many deficits of airships, but the concept continues to strike the imagination of some people, who keep looking for an application where they might be practical.
The reasons why people are drawn to this notion are complex. Airships have a retro-futuristic appeal, and were once assumed to be the future of transportation. The idea of these vast vessels floating in the clouds seems almost fantastical, but they existed as a real and practical technology for a significant amount of time. Some like to imagine that, had technology developed differently, they might continue to be an important technology today (which makes them a fixture in sub-genres like steampunk).
In real life, there area number of present and recent endeavors trying to commercialize modern airships. Shortly before this strip, there was a flight test by Sceye, Inc. of a helium-filled airship designed to replace cellular communication towers. Commercial airships have also been proposed by CargoLifter (which burned through $300 million before liquidation), and by Flying Whales, which at the time of this comic had been in existence for 14 years but has yet to produce a prototype. The patterns of such companies forming and then failing to produce viable products supports the central thesis of the strip: that many people really want airships to make sense in modern times, but can never make it happen. There are also 6 airships made by Zeppelin NT currently in operation.
Randall is likely among the number that would like to see airships return, judging by the frequency with which they appear in his strips.
Transcript
- [At the top of the panel:]
- Aerospace engineer problem-solving flowchart
- [Below that, in a flowchart box:]
- Start
- [Arrow pointing downward to a flowchart diamond:]
- Could we solve this problem by building giant airships again?
- [The only arrow from the diamond is labeled "No", pointing downward to another flowchart box:]
- Try other solutions
- [Four arrows pointing out of the box to the bottom of the panel.]
This Week's Explanation for Improvement
As part of the Explanation Improvement Project, each week the community selects one older, neglected, or otherwise stagnant explanation to expand and polish together. This week's pick is comic 395: Morning; help us by editing its explanation!
To get involved with the project, you can also nominate an explanation that you think should be improved, or vote on current nominations!
| Morning |
 Title text: I'd press on them to try to unstick them, but I can't reach. Can we try cycling day and night really fast? |
Explanation
|
Welcome to This Week's Explanation for Improvement! Anyone is encouraged to help explain comic 395: Morning; click here to get started! If you are new to wiki editing, you can read our editing FAQ for guidance. Here are some suggestions for improving this explanation: .svg){kind=icon} Explain the references to The Matrix to someone who has never heard of the movie.
.svg){kind=icon} Explain the "screen resolution of the world" in first panel. Is there truth to this? What resolution do our eyes actually have?
.svg){kind=icon} Explain the title text, especially "cycling day and night really fast".
.svg){kind=icon} The explanation of LCD screens is too technical.
|
This comic plays on the idea that physical reality might be a simulation running inside a supercomputer. This idea has been explored in popular culture before, as mentioned in the comic itself, but the second panel argues the revelation would still be a deeply existential horror of it were true.
The first panel mentions The Matrix, a 1999 action movie where the main character Neo discovers that the world he thought he knew was actually a simulation being run by an army of robots who keep the human race hypnotized inside the titular simulation. It is perhaps the most famous work of fiction to touch on the theme of reality being a simulation, and an easy cultural touchstone at the time this comic was written (thus her claim "We've all seen" it).
The reveal of Megan's reality being a simulation comes when she sees "dead pixels" in the sky. In LCD screens, especially TFT LCD, a dead pixel is a pixel that does not work properly, usually set as black or as some other color. LCD screens were a more common standard when this comic was written, but have largely been supplanted by LED screens wherever possible. Megan realizes that the reality is a computer simulation when she sees dead pixels in the sky, indicating that what she sees is an LCD screen.
In the last panel of the comic, there are three pixels — two red and one green — that look exactly like actual dead pixels.
Regarding the question in the first panel, "What resolution is life?" (by which "life" presumably means the "real world" or lived experience, not living biochemistry), the most scientifically meaningful response would involve Planck distance and Planck time, the smallest digital units of distance and time that time-space can be broken down into. Humans, of course, cannot perceive on that scale, but it is the fundamental building block of the time-space around us, similar to pixels (picture elements) on a screen or a bit (one-or-zero) of data. Datum. Data. Our experience occurs at a much higher level, so a lower order of resolution. Note that the trees are not pixelated, meaning that only the sky is a giant LCD screen.
The title text refers to usual techniques for fixing a dead pixel. One way is to apply pressure and release it, which isn't possible for Megan due to the distance of the sky. Another way is to make the area of the screen that the dead pixel is on change colors really quickly, which could happen if the day-night cycle was fast enough, or if the clouds overhead were sped up.
Transcript
- [Megan is standing to one side.]
- We've all seen The Matrix
- We've all joked about "What resolution is life?"
- But it doesn't blunt the shock
- Of waking up one morning
- [Megan looks up from field and sees several colored pixels in the sky.]
- And seeing dead pixels in the sky.
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