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| Second Stage |
 Title text: Hmm, they won't do in-flight delivery, so let's order a new first and second stage to our emergency landing site and then try to touch down on top of them to save time. |
Explanation
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This explanation may be incomplete or incorrect: Created by a BLUE ORIGIN DELIVERY DRIVER - Please change this comment when editing this page. Do NOT delete this tag too soon. |
In this comic, two people have lifted off in a staged launch vehicle without their second stage installed. This is unlikely to happen in real life, because rocket launches are thoroughly planned and checked and the lack of an entire stage would be glaringly obvious to anyone who is part of the project, but can be a problem in games such as Kerbal Space Program.
Staging in rocketry refers of the segmentation of a launch vehicle into distinct, separable modules, each one with an independent Rocket engine (or engines) and fuel supply. This is practiced for two critical reasons: firstly, different engine designs work better at different altitudes, so you'd want to use one engine type deep in the atmosphere and a different engine once you get to space; and secondly, since you only need one of those engines (or sets of engines) at once, it'd be better to simply expend the first engine(s) and its fuel tank once you no longer need it. By getting rid of that useless mass, you can go farther using the same amount of fuel. A launch vehicle that does not employ staging is called an Single-stage-to-orbit (SSTO), but none of them have been successful due to the technical challenges. There's a tradeoff between the greater effectiveness of different engines under different conditions, and the mass penalty of having to have multiple engines as well as extra hardware that can be separated.
As Pilot 1 calls to fire the second stage, Pilot 2 is initially confused and asks if a second stage was needed. Pilot 1 confirms that there was supposed to be a second stage, and thought that it was the Pilot 2's responsibility to install and confirm there was a second stage. When both pilots realize there is no second stage, Pilot 2, naturally, thinks he can order one on Amazon with same-day delivery (though Amazon typically doesn't sell space ship stages - at least not with same-day delivery[citation needed]). He then has difficulty picking an address ZIP Code as they are likely traveling too high above the ground and too fast to be in a single postal area for long enough for the delivery to take place. The joke is likely poking fun at people who forget to pack certain items when going on road trips or vacation, and rely on Amazon to deliver replacements to them. There is also humor to be found in this rocket apparently being designed, built, and piloted by only two people — in real life, the construction of a rocket, especially a manned one, involves thousands of people, and although test pilots have input in the development of many vehicles and many were chosen for various space programs, generally they do not do the designing themselves.
The comic also alludes to a not-so-distant future when space travel is a much more mundane endeavor. If companies such as SpaceX succeed in their mass-production and launch cadence goals, one could imagine a scenario where rocket parts become standardized and easily replaceable-- similarly to how it is easy today to replace a car's tire or fill its fuel tank if you get stranded on a highway.
In the title text, Pilot 2 concludes that in-flight delivery won't be possible but proposes to have a new first and second stage delivered to their emergency landing site so they can pick them up and continue on their launch without stopping.
This is not the first time Randall discusses the idea of a mid-flight delivery. A What If? explanation attempts to answer if it possible to have pizza delivered to you, by a bird, while flying on a commercial airliner.
Trivia
- The rocket, though apparently at least one segment short, appears to be substantially taller than the launch tower of the pad, which is a strangely incongruous detail. Unless the real rocket support is an angled back "hard spine" structure that has been rotated out of the way and down into the exhaust-flume/flame-trench quenching system. Since the voices are coming from what appears to be a separate module at the top of the rocket, it may be that the shell of the second stage is present, but not the engine and/or fuel.
Transcript
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This transcript is incomplete. Please help editing it! Thanks. |
- [A multi-stage rocket, with a capsule on top, is lifting-off the ground from a launchpad, at least two rocket nozzles are visibly producing a flame, and the pad is surrounded with smoke and/or steam from the blast suppression system. A voice comes from the capsule at the top.]
- We have liftoff.
- [The first stage separates from the rest of the rocket, part way through the roll-program. There are no obvious engines standing out from the 'second stage' (or extended payload trunk) lower shroud.]
- Main engine cutoff.
- Stage separation confirmed.
- We are go for second stage burn.
- Second stage?
- Yes.
- ...What?
- [The first stage and the rest of the rocket are drifting apart in apparent freefall. No rocket is firing and the background does not seem to indicate that this view is beyond the atmosphere.]
- We were supposed to have a second stage?
- ...Yes!
- Did you set up a second stage?
- I thought you were handling staging!
- Oh no.
- [They continue to drift apart slowly.]
- Okay, don't panic.
- Lemme see if we can order a stage online for same-day delivery.
- Sigh.
- Hey, what zip code should I put? Ours keeps changing.
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