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Cargo airships could be big

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Re: Cargo airships could be big

#211

Post by nradov »

vintermann wrote: post #83
rsynnott wrote: post #37

Earlier quoted context omitted.

Partially or completely wind-powered cargo ships appear to be on the way, so this might happen anyway.

Personally I'm pretty disappointed that hobby drones use so much power, when the seagulls just glide out there, not even flapping their wings for minutes on end. We should be able to manage the same with microcontrollers now, surely?

We've been able to manage the same even without microcontrollers. Radio controlled model gliders and sailplanes have been popular among hobbyists for decades. I see them flying at a local park all the time.

Re: Cargo airships could be big

#212

Post by AlgorithmicTime »

stopping wrote: post #158
padobson wrote: post #93

Earlier quoted context omitted.

Massive airships flying 90/km an hours are LESS susceptible to blockades than cargo ships? I think I'll need a little more explanation than that. Seems like a shoulder-mounted rocket launcher would be more than enough to bring one down.

Or a single tracer bullet, if it's filled with hydrogen.

Apparently that's not actually the case. The Brits and French had a hell of a time shooting down German Zeppelins in WWI with standard tracer ammo.

Re: Cargo airships could be big

#213

Post by avereveard »

bruce511 wrote: post #180
criddell wrote: post #167

Earlier quoted context omitted.

> high octane fuel Doesn’t jet fuel have a relatively low octane rating compared to most liquid fuels?

It depends on the plane, but both your point and the parent point are correct. Piston engines run on high octane gasoline (Avgas) . This is the stuff that powered planes up to, and just past, ww2. Today it's still used in planes from that era, and some smaller general aviation planes. Jet fuel (jet a1) is basically paraffin. All turbine engines (think "jets", but also turbofan etc) run on this. It's a lot less flamma…

You can dump plane fuel before an emergency landing, making the whole process safer. it's not just double standards.

Re: Cargo airships could be big

#214

Post by kbenson »

echelon wrote: post #33
splitrocket wrote: post #12

This, my friends, is why we should colonize the upper atmosphere of Venus, where you could chill outside with only a respirator, rather than the inhospitable, irradiated, mangnetosphere free mars. https://en.wikipedia.org/wiki/High_Altitude_Venus_Operationa... https://spectrum.ieee.org/nasa-study-proposes-airships-cloud...

I've always felt people with these ideas are doing pie in the sky thinking and missing the other trends that would beat this concept out. Humans aren't suited for these environments. We evolved to fit this planet. These gasses, radiation levels, terrestrial foods, etc. The economics of going to Mars, Venus, etc. are iffy, and humans probably won't enjoy being there. It's McMurdo times about 1000. Getting back is hard…

As long as the AI we create treat us with the love and respect we treat our pets with, we'll colonize everywhere, even if they have to clone us on site.

Oh, the breeds we'll see... or be.

Re: Cargo airships could be big

#215

Post by wefarrell »

blamestross wrote: post #47
splitrocket wrote: post #12

This, my friends, is why we should colonize the upper atmosphere of Venus, where you could chill outside with only a respirator, rather than the inhospitable, irradiated, mangnetosphere free mars. https://en.wikipedia.org/wiki/High_Altitude_Venus_Operationa... https://spectrum.ieee.org/nasa-study-proposes-airships-cloud...

Hang on tight for those gentle 185 mph breezes...

Only a problem if you're anchored to the surface. Otherwise it's the changes in windspeed that you have to watch out for.

Re: Cargo airships could be big

#216

Post by Johnny555 »

LarryMullins wrote: post #132
coryrc wrote: post #123

Earlier quoted context omitted.

It's not safe for us to be breathing. But that doesn't matter to cheapskate rich private plane owners or their regulatory-captured FAA.

The really rich private plane owners all have planes that burn jet fuel, which is always unleaded. The piston planes are generally owned by "doctor rich" upper-middle class people, who have political influence to be sure but they're hardly the billionaires that might be known by name to politicians. I think it's more likely that the FAA protects general aviation because general aviation is part of the professional pi…

The people that are below “doctor rich” just rent their planes from the FBO, a cheap piston plane can rent for $125-$175/hour. So you can get in a couple hours of flying for what it costs a couple to go to a football game.

Re: Cargo airships could be big

#217

Post by throwaway894345 »

bruce511 wrote: post #180
criddell wrote: post #167

Earlier quoted context omitted.

> high octane fuel Doesn’t jet fuel have a relatively low octane rating compared to most liquid fuels?

It depends on the plane, but both your point and the parent point are correct. Piston engines run on high octane gasoline (Avgas) . This is the stuff that powered planes up to, and just past, ww2. Today it's still used in planes from that era, and some smaller general aviation planes. Jet fuel (jet a1) is basically paraffin. All turbine engines (think "jets", but also turbofan etc) run on this. It's a lot less flamma…

> Hydrogen is also dangerous, and there does appear to be a double standard here.

I don't have beef with hydrogen, but I suspect it's a lot easier to secure fuel in a liquid state versus a gaseous state. Putting a lot of hydrogen in a relatively small steel container for use in an engine seems quite a lot safer than putting it in a big bubble and then dangling people from it. But I am not an aerospace engineer, could be wrong, etc.

Re: Cargo airships could be big

#218

Post by jillesvangurp »

andrewflnr wrote: post #86

The suggestion to use a magnesium frame, in combination with hydrogen for lift, is kind of hysterical. Why not use a flammable metal with your flammable lifting gas? I won't even be shocked if it works, but it would still be a hell of a thing.

You need oxygen to get to the flammable material to burn it. For magnesium that means grinding it to a fine powder that burns really quick. Otherwise, it will just oxidize at the surface and be quite boring and inert. It's a common metal used for all sorts of engineering. E.g. German WWII era planes used some magnesium parts.

Iron also burns if you grind it to a fine powder. You can try that out if you have some steel wool. It's just an exothermic oxydation process. The more surface area the hotter it burns. Magnesium just burns a bit hotter. Most of the colors in fireworks are just different metal powders burning.

And for hydrogen, you need to mix it with oxygen to get a flammable mixture. So, a large mass of hydrogen is explosive in the same sense that a few tonnes of kerosene is explosive. I.e. not that much at all. Also, hydrogen is light. If you have a leak you go down, and the hydrogen goes up very rapidly. It doesn't stick around.

They did this routinely in the 1930s. It wasn't much of an issue then. The theories of what happened to the hindenburg vary a bit but it seems as it didn't explode so much as burn. Probably most of the hydrogen escaped before it could burn.

https://en.wikipedia.org/wiki/Hindenburg_disaster

Interesting read. Quite a few people actually survived. I'm sure these things could be engineered to a much higher safety standard now.

Re: Cargo airships could be big

#219

Post by natpalmer1776 »

chatmasta wrote: post #171
stopping wrote: post #158

Earlier quoted context omitted.

Or a single tracer bullet, if it's filled with hydrogen.

Surely you could design some redundancy into the hull? It's not like the ship needs to be one giant gas bubble. It can be a mesh of a few hundred bubbles that could each pop without bringing the whole thing down.

So… 100 tracer bullets instead?
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