keepthepace
@keepthepace@slrpnk.net
- Comment on High Altitude Solar Cruise 1 week ago:
The fact that you assume I don’t understand that basic fact clears that out that this is not a serious discussion. You think “plane, heavy, need fuel” “blimps cool, lighter than air” and work your calculations from there. I am sad I wasted so much time in it.
- Comment on High Altitude Solar Cruise 1 week ago:
Ok so scaling blimps up is realistic but planes not, no justification needed. I see, ok, bye.
- Comment on High Altitude Solar Cruise 2 weeks ago:
10-20 American football fields in size.
So about 20 times the biggest wing area that we currently have? Is this what you are scolding at? Is this your physical impossibility?
What’s the obsession with blimps by the way? If you are afraid by enormous sizes please tell me you have done the calculations there…
- Comment on High Altitude Solar Cruise 2 weeks ago:
Let’s be clear, without joking I think you are wrong to dismiss these possibilities and that you have an almost pathological lack of imagination. Yes, science fiction is about techs that do not exist yet are plausible.
You can fit a pool and a greenhouse in 250t. 40 cubic meters of water is 40 tons, 40 cubic meters of soil is basically the same. You have room to spare for the tennis court.
I am not a pro aviator, but I am a pro engineer, on an unrelated field, but I can do my napkins calculations. I mentioned the An-225 to make a point on the physically possible payloads that are possible today, with proven tech. I am not proposing we need those neither do we need the exceptional specs of that exceptional plane.
We scale down speed, it scales down drag (and necessary thrust) quadratically. We assume better efficiency on solar panels, batteries and motors because that’s what we will have in the future. Needing thrust only for sustaining flight and not for take off is another x5 factor on your calculation.
you’d still need at least 40 000 - 150 000 m2
Look at you! You managed to scale down your initial super confident 600 000 m² estimate by an order of magnitude! I am proud of you!
but as a wild guesstimate, I’d say the an255 needs some 40 000 to 120 000 kW for sustained flight in fair weather.
From what I am reading this is about the amount of power an airliner uses at max power on all the engines. You are looking at 1/10th to 1/20th of that for sustained flight, and quadratically less at lower speeds that those typical of those airliners.
- Comment on High Altitude Solar Cruise 2 weeks ago:
We do have helicopters. We have canadairs, we have hovering drones.
You are arguing about a technicality that has been worked around.
- Comment on High Altitude Solar Cruise 2 weeks ago:
Dammit, here I am, arguing over the feasibility of a fantasy, between a hamster in warhammer gear and a knitted armor. sigh
Dude chill, I merely mentioned the An-255 because you sounded like you were arguing that flying a pool and a greenhouse was somehow breaking a law of physics. It does not, you can fly both for the 250t (that’s payload only btw, that does not count fuel(+300t!), engine, structure) that this plane can lift.
I am not proposing to develop the same amount of thrust, speed, dry range that it exhibits, these are different beasts. Actually, in my fiction, these “sky palaces” only have the thrust needed for sustained flight, and can’t lift off unaided.
Now don’t get me wrong I’m no nuclear shill,
I am, but I am also an avid dreamer of new tech.
The record for efficiency for solar panels in a laboratory setting is 47%. Those aren’t commercially available. Commercially available ones are currently around 22%.
Sci-fi setting, honey. If 47% is achieved in the lab that’s the bare minimum of what is credible for future tech.
I am happy you made the calculation for something that can drag 300t of batteries at half the speed of sound and can produce the constant thrust the An-225 needs for take-off but that was never the proposition. I am proposing a slow vehicles, with a fairly big lift due to its large wings so probably able to fly at a much lower speed, generating far less drag, drag being the main lower bound for the thrust needs. Probably going at speeds where propellers are much more efficient than jet engines. All of this adds up to levels I don’t care to calculate because this is a fantasy.
However yes, that’s a proposition that still requires extremely large wingspans. And yes, putting a swimming pool in an airplane is kind of a ridiculous proposition, but it is kind of the point I want to make: nowadays that would be a very wasteful ridiculous thing to do. With this sort of tech? It does not harm anything or anyone. It does not burn fuel, it does not emit CO2.
All I know for sure is that eternal planes are a thing that is possible right now, and that better tech will allow us to make them bigger.
- Comment on High Altitude Solar Cruise 2 weeks ago:
Yes and? You do know that current cargo planes are able to lift 250 tons without violating the laws of physics?
- Comment on High Altitude Solar Cruise 2 weeks ago:
Just to be clear “eternal planes” exist today. They use solar during the day, batteries during the night. Unmanned they last forever and a 2-person plane like this already exists now.
What I am proposing is science fiction, but honestly the most straightforward and boring kind: I am proposing that from this current state, we will continue, percent by percent, improve efficiencies in batteries, motors, solar panels, we will improve material resistance and aeronautic designs.
- Comment on High Altitude Solar Cruise 2 weeks ago:
Oh this is just the dining Cupola, you should see the greenhouse and the swimming pool if you think it is cramped up!
Why not just use a helium blimp instead?
Why use non-renewable helium when you can just use more elegant, more renewable, more steerable solar power?
(In all seriousness, I am trying to give an idea of a high-tech sustainable future that’s not just “small scale farming with solar panels”)
- Submitted 2 weeks ago to stable_diffusion_art@lemmy.dbzer0.com | 21 comments
- Comment on Looking for transcendence 3 weeks ago:
Transcendence is not for the cold feet.
- Submitted 3 weeks ago to stable_diffusion_art@lemmy.dbzer0.com | 2 comments
- Comment on Cry Harder, Kid 2 months ago:
If you have never seen a scallop run away, google it.
- Comment on She-Ra Lives! 2 months ago:
Personally I find it weird that we do generalities about a this population as it is very likely that they had all different cultures on the tribe level.
- Comment on Amateur Entomologists 2 months ago:
Nah the game is about friendship and time travels. The boss is kinda irrelevant.
- Comment on Amateur Entomologists 2 months ago:
The court was one of the best moments!
- Comment on Penguins 🐧 2 months ago:
PENGUINS! IM TALKING ABOUT PENGUINS!
- Comment on Amateur Entomologists 2 months ago:
Chrono Trigger is fun!
- Comment on Amateur Entomologists 2 months ago:
In DnD I believe it is called a Tarrasaque
- Comment on DNA Horror Movies 2 months ago:
I’d roll my eyes over the last one but instead I just spinned them.
- Comment on Womp womp 2 months ago:
Yes, they get confused with us evil engineers.
- Comment on smart engineering 2 months ago:
That’s not the history of that thing: en.wikipedia.org/wiki/Up_to_eleven
- Comment on IS THIS REAL CHAT?? 2 months ago:
THANK GOD YES! Imaginary matrices are a pain to multiply!
- Comment on A decline in arable land 2 months ago:
Is this a bad thing? I always heard that here in France we have increasing forest coverage.
- Comment on Ahoy me hearties 2 months ago:
Alexandra Elbakyan deserves a Nobel and a presidential pardon. I doubt any other person alive now has made more for science.
- Comment on Pick some unrelated lectures, they said. 2 months ago:
A someone not in the field (CS/Machine learning) what did you expect these to be?
- Comment on Pick some unrelated lectures, they said. 2 months ago:
But… but… these are my maths shoes!
- Comment on Publishers Always Innovating 2 months ago:
Yes, PDFs are much more permissive and may not have any semantic information at all. Hell, some old publications are just scanned images!
PDF -> semantic seems to be a hard problem that basically requires OCR, like these people are doing
- Comment on Publishers Always Innovating 2 months ago:
I love that PDFs are so difficult to transform into HTML, too
FYI, if that’s relevant to your field, every new article published on arxiv.org now has a HTML render as well.
And on many older publications, transforming “arxiv.org” into “ar5iv.org” leads to an HTML rendering that is a best-effort experiments they ran for a while.
- Comment on Publishers Always Innovating 2 months ago:
You are welcome.
