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Comment by stanski | Hacker News Reader

To be fair, the time difference between a jet airline and blimp would be a lot bigger than 3 times or so. 7 hour in a metal tube vs 5 days in a blimp sounds more realistic.

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Cruising speed in an A380: 560 mph (900 km/h) [1] Cruising speed of the Hindenburg: 76 mph (125 km/h) [2]

That's a multiplier of 7.2, though the shorter the flight the more pronounced an airship's time to reach cruising speed and come back down from cruising speed will factor into the overall ratio. And this assumes we can't make airships go faster than the Hindenburg (is 155mph/300km/h unreasonable?).

[1] https://en.wikipedia.org/wiki/Airbus_A380#Specifications [2] https://www.airships.net/hindenburg/size-speed/

Airships couldn't fly great-circle routes of shortest distance, so the actual distance would be much longer. They did pressure-flying, skirting around weather formations like a helicopter flying through mountains. Sometimes they could get a slingshot by riding a wind as it flowed from a high.

Maybe for airships/blimps the approach would have to be different than for airplanes, meaning more intermediate stops? (maybe their "landing/takeoff"-cycle is more efficient than the ones of airplanes?) Kind of bus/tram vs. trains?

Or maybe just complementary? E.g. long routes handled by airplanes, "medium" routes handled by airships/blimps, and the rest handled by trains/bus/whatever?

I suspect we could do much faster landing/takeoff in airships nowadays than before, with dynamic positioning and azimuth thrusters or similar (rather than relying entirely on tether lines and/or mooring towers). It might be possible to have a faster cycle than airplanes due to VTOL abilities and more on-board infrastructure allowing for landings at smaller airfields than most commercial flights are able to use - though I imagine most local airfields would require some degree of retrofitting before they could support airship landings.

While I doubt they will ever be a primary transportation medium, I wonder if there would be enough demand for a cruise-ship-style airship to be commercially viable; I for one would absolutely love to spend a month on a luxury cruise around the world, landing every other day without the limitations of only seaside locations.

there is well forgotten middle ground - large and relatively slow (say 200-300mph using today's tech) plane, something like this https://en.wikipedia.org/wiki/Dornier_Do_X

"As a result of its size, passengers were asked to crowd together on one side or the other to help make turns."

That's amazing

Somewhat unrelated, I’ve been wondering for a while whether all pax in concert moving to the front/back of the cabin could bring a jet out of its flight envelope. There’s one or two related aviation stack exchange questions (that I’ve contributed to, IIRC), but I’ve never seen an informative authoritative account.

Abso-freaking-lutly. The permitted range for the CG (longitudinally) — denoted as "% of MAC", for Mean Aerodynamic Chord — is quite narrow, and you prefer to stay away from the "edges" of that range whenever possible.

The distribution of pax and baggage are chosen so as ensure its within the range. IOW, they don't book Row 1 then 2 then 3, etc, — sold seats are sprinkled across the aircraft as it's filled.

I've been told when the flight attendants are moving forward and back with the beverage service you can watch the trim wheel turn as the autopilot maintains correct AOA.

I did recall one incident where the plane got out of balance because of passengers moving in concert.

https://www.indiatoday.in/india/story/asaram-bapu-rape-accus...

On the ATR-72 [0] there is an extra leg that folds down at the back of the plane to stop it tipping over, and passengers at the front half must remain seated until the rear pax have left, so there must be some danger of unbalancing. These are weird planes in that the cargo is stored at the front, behind the pilots, and the only door is at the rear. They are prop planes, the 72 being a stretched 42, I believe.

0. https://en.wikipedia.org/wiki/ATR_72

There was a plane crash in the Congo that was reportedly due to everyone running away from a crocodile. https://en.wikipedia.org/wiki/2010_Bandundu_Filair_Let_L-410...

When flying a small airplane in Asia we were all weighted individually, and distributed around the plane accordingly.

I read about other flying boat - Boeing-314. It seems that it was basically 74 first class equivalent passengers and it was very expensive in its time. Converting it to cattle-class economy maybe could push it to 100-120 or so passengers. It would still be very expensive due to inefficient flight profile and high fuel consumption. Limited routes too. They are very pretty though, I'm not denying that.

Pan Am's Clippers were basically modeled after the luxury trains of the era, divided in compartments with seats that could be converted into bunks, and a common dining lounge: https://airandspace.si.edu/sites/default/files/images/7146h....

I think the problem with these is that they're terribly inefficient. Large plus slow equals low altitude, which means thick air.

Maybe it'd be possible to revisit nuclear powered aircraft? Modern, intrinsically safe reactors powering turboshaft engines could keep a ponderous flying platform aloft for months at a time.

I don't know much about modern reactors but I suspect even 3rd gen ones will still require immense shielding of a cabin and will be single contour design, meaning that exhaust will be irradiated, maybe less so than on prototypes from cold war. And as I remember soviet Tu-95LAL that did flew with a reactor did so WITHOUT any significant shielding for the crew.

I'm not sure there's value in debating that. It is a hypothetical blimp that doesn't exist.

Blimps can't go all that fast.

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