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A comment on Boom Supersonic raises $100M, aims for 2019 test flights. Parent comment

Re:Boom Supersonic raises $100M, aims for 2019 test flights by TylerE on Saturday January 05, 2019 @02:39PM (#18833727)
No. The payload fraction is just too poor. For instance, the Hindenburg, which was the largest, most advanced Zeppelin ever built, had a payload capacity of only 21,000lbs. That's using hydrogen, which, is, obviously not real safe. If it had used helium instead, it would have had a payload capacity of -34,000lbs.

For comparison, a single 40' standard container has a maximum load of 57,000lbs, and a large cargo ship can carry thousands of those.

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Re:Boom Supersonic raises $100M, aims for 2019 test flights by FlyMoreRockets on Saturday January 05, 2019 @08:22PM (#18835668)
What was the mass of the Hindenburg without the lift gas? Doubtless modern composites could significantly reduce that mass, which could go directly into increased payload.

Alternatively, an airship of the same mass of the Hindenburg could be made significantly larger, and since payload scales with the lifting gas volume, payload would also increase.

Oh, and throw the Hindenburg's aluminum piano over the side.

I note with interest that you say the Hindenburg would have had a greater payload with Helium rather than Hydrogen. Why do you say that?

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Re:Boom Supersonic raises $100M, aims for 2019 test flights by TylerE on Saturday January 05, 2019 @08:27PM (#18835700)
> I note with interest that you say the Hindenburg would have had a greater payload with Helium rather than Hydrogen. Why do you say that?

I did not say that. Note the negative.

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Re:Boom Supersonic raises $100M, aims for 2019 test flights by FlyMoreRockets on Saturday January 05, 2019 @08:52PM (#18835842)
I saw the dash, but didn't understand it. If the payload with hydrogen is 21,000lbs and it is -34,000 pounds with helium, then it seems like it wouldn't even get off the ground. But clearly, it did get off the ground with passengers using helium, it was designed to fly with helium.
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Re:Boom Supersonic raises $100M, aims for 2019 test flights by TylerE on Saturday January 05, 2019 @10:15PM (#18836330)
No it wasn't. The German Zeppelin's always run hydrogen. At the time the US had the only real supply of helium and they wouldn't sell to Germany.
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Re:Boom Supersonic raises $100M, aims for 2019 test flights by FlyMoreRockets on Saturday January 05, 2019 @10:18PM (#18836343)
Okay, I stand corrected about it flying on helium, thank you for correcting me, +1. However, the Hindenburg was designed to fly using helium as the lift gas.

https://en.wikipedia.org/wiki/Hindenburg-class_airship#Lift_...

The article goes on to say the difference in lift between hydrogen and helium is only 8%.

Edit: drop the apostrophe on zeppelins

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Re:Boom Supersonic raises $100M, aims for 2019 test flights by TylerE on Saturday January 05, 2019 @10:45PM (#18836433)
8% of 500,000lbs is....
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Re:Boom Supersonic raises $100M, aims for 2019 test flights by btrettel on Saturday January 05, 2019 @04:06PM (#18834260)
Thanks for posting. These are interesting figures that show airships are not as good as I suspected.
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