xkcd #3298: Aerospace Flowchart
Title text:
Someday, we will find the problem that goes with this solution.
Transcript:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3298/
There is hope though:
- America has it’s own no joke airship to orbit program
- Airlander will hopefully soon start to fly short haul flights in Spain (and like 20 of them)🤞🏻
pretty please?
But how do we convince investors to fund huge airship hangars in low density regions? They need adventure pools too, you know?
I find it hard to believe that there are problems you can’t solve with giant airships.
As the Total War 3 mod which basically turns the Empire into a ww1-ww2 era power has taught me, if you can’t solve a problem with zeplins you aren’t using enough of them. Now if you’ll excuse me the Karl Franz zeplin armada has some French to purge.
you’re right. i bet my cat would be less gassy if we lived at altitude, too
i’m not sure i would change that tho, she seems to enjoy farting on people.
If we made them extremely luxurious and everyone agreed that only the “best” people could use them for travel, I could see them solving a few problems.
I feel like you’re ignoring how cool massive airships are
Can confirm, I went on a Zeppelin flight earlier this summer, can absolutely confirm that it was damn cool.
I find it odd that the answer is ALWAYS no. Surely at least one problem has been solved by building giant airships.
Mass transport (of rich people and military) before the invention of the jet engine.
Airships are the most expensive, worst and most dangerous solution to any problem.
i disagree. you could build catamaran-style airships.
that sounds far more expensive and more dangerous.
not worse though, that sounds way cooler.
Building a worse airship is still building an airship.
And name them Akron and Macon.
i was going to name them after match companies but i like your idea
Oh you must be European, if you’re concerned about fires aboard airships. American airships don’t burn; we’ve never been stupid enough to use hydrogen as a lifting gas. USS Akron and USS Macon both crashed, much of the crew of one froze to death and the other proved surprisingly survivable. Compare that to the Hindenberg or R-101.
These are good priorities. We fumbled her so badly
Last month I went on a Zeppelin ride, there are some tasks that airships do well. Tourism tours, long term temporary monitoring, some specific geo surveys and advertising.
High altitude airostat balloons have also been considered as a superior alternative to satellites for some applications due to lower ping and greater resistance to solar activity. Unfortunately it turns out its also harder to make a long lasting high altitude balloon with consistent positioning than it is to launch something into space.
Wow, I’m envious!
There are still airships in operation? I thought it was blimps only
Yeah, though to be fair a blimp is a type of airship.
However, the Zeppelin I flew on and the Goodyear Blimp are not blimps, they are derigibles.
Whoa. Good for you.
And for radio relays. Although that’s more of a balloon job.
Here are some pics:
We should do it anyway, just to be sure.
But what if the problem is that you want to be able to hover in one place and lift stuff without having to continuously spend energy on enough thrust to push that weight upwards?
Slap a camera and a bunch of batteries on a balloon and you can easily map large areas without recharging. Great for photogrammetry. You can also carry other instruments onboard.
Lifting stuff with an airship is surprisingly terrible.
Why?
Our old arch nemesis, physics…
The problem is not that you can’t build an airship that can lift say ten tons of cargo.
The problem is what you do when you remove the cargo from the airship.
Without the cargo, the airship will be ten tons light, you would need to make sure you could hold it down against a lifting power of ten tons.
Ok, so let’s just fill it with water on the return journey, easy!
How would you do that in sync with removing cargo, the cargo which probably is a cargo container, and is just disconnected, you can’t just suddenly move ten tonnes of water onboard the airship, it takes time to fill up.
Ok so you get another container with a dummy load to enable a simple connect disconnect at the loading dock, fine that would work, apart from what you would do when the next load arrives, do you just manufacture dummy loads and take them back to the start, how do these get back to the other side where they are needed, and why don’t we use the same method to move the initial cargo?
How would you do that in sync with removing cargo, the cargo which probably is a cargo container, and is just disconnected, you can’t just suddenly move ten tonnes of water onboard the airship, it takes time to fill up.
A cargo container of water? You’re literally throwing your hands up at the smallest issues and pretending you hit mount everest.
Not to mention there’s no requirement the weight has to stay the same. Inflating and deflating the balloon controls the buoyancy.
A few solutions I could think of right off the bat:
- A logistical network so that not every A-B path has to be a net-zero-mass trip, only the nodes - reduces dummy load requirement
- Mass congestion pricing to help balance out the nodes
- Large water bags, send them back empty
- One-way airship travel tourism, brings extra revenue and publicity as a plus
Ok so you get another container with a dummy load to enable a simple connect disconnect at the loading dock, fine that would work, apart from what you would do when the next load arrives, do you just manufacture dummy loads and take them back to the start, how do these get back to the other side where they are needed, and why don’t we use the same method to move the initial cargo?
If you just have a tank for the water, you could just fill it before unloading.
Then you would need a heavier structure to be able to support twenty tons in total, ten tons need to be supported by the landing gear.
This makes things heavier.
Also, where do you get ten tons of water from, where you at the same time can’t drive a truck?
Only carry liquid cargo, pump out of the cargo tank at the same rate you pump into the water tabk. You’d be able to maintain ten tons to an acceptable margin of error.
Clever idea!
Vacuum the lifting gas out of the giant balloon into some storage tanks to compress it and use some smaller balloons as a tiny giant airship to transport the apparatus back?
You need the lifting gas to fill out the envelope and maintain structural integrity, a floppy envelope isn’t amazing at control
Maybe some balloon animal structures inside the balloon to give it a shape?
I started off being a bit silly, but this question is serious. If you had a magic material that was rigid and could maintain that inflated shape for the same weight as the current material they use, could you selectively change its buoyancy by vacuum? Don’t submarines and fish with their swim bladders do the same thing? That would make it a materials problem correct?
Ok, say you have an extremely lightweight yet strong material that you could make a large vacuum chamber out of. It would be quite effective as a lifting device.
And as you note, regulating the pressure inside with bladders would enable you to adjust the buoyancy, this is actually a system that the modern Zeppelin NT uses, though not for adjusting lift in response to loading/unloading, more as a general setting for the area and air pressure.
The NT is usually calibrated to weigh about 300kg and uses movable propellers to move up/down and relies on the airfoil shape of the inflated envelope to generate the tiny amount of lift to stay up while moving forward.
As I always say: Physics knows no favours and no bosses.
Boss wants me to do something that physic doesn’t allow? I laugh at him for his hybris. No, won’t work, because… See first line of this comment.
how hard would it be to have a big anchor that offsets the weight of a couple cargo containers while it fills a ballast with water?
A winch and cable, a balloon and a comfy basket, enough wine for a weekend. - Sales pitch for my floating AirBnB.
What about huge underwater submersibles ?Won’t someone think of the captains obsessed with the cleanliness of sheets?
I noticed the lack of a ‘Yes’ flow.
Could we put an airship in Venus’s atmosphere? It seems like it’d be more useful than sending something to the surface, but I know nothing about the engineering involved.
For a short time, maybe. Until it is shred to pieces or dissolved by the atmosphere I would guess. But I’m not an aerospace engineer. :)
No, it’s actually kind of an idea that people have thought about. The upper atmosphere on Venus is a kind of OK environment and because of the thick atmosphere, it’s even easier to float there than on earth. The trouble really starts when the acid clouds begin.
Good to know.
The trouble really starts when the acid clouds begin.
Yes, it’s always the same with acid clouds.
I studied aerospace engineering. Can confirm
sadly there is no yes line in first triangle of flowchart.
