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Comment by louprado | Hacker News Reader

We may (or may not) have a helium shortage[1] and it requires surprising effort to ignite the hydrogen in an airship[2].

Perhaps we should reconsider if our hydrogen ban is warranted for autonomous or remotely piloted airships. Note, the article makes no mention how this airship is piloted, but its primary use is to supply humanitarian relief missions.

[1] https://www.wired.com/2016/06/dire-helium-shortage-vastly-in... [2]https://youtu.be/wzW4258oIyg?t=46m56s

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> it requires surprising effort to ignite the hydrogen in an airship

They burned like tinder, in large numbers. The following is a list of hydrogen-filled airships which burned. These exclude losses due to enemy action.

  1902, *Pax* explodes over Paris
  1908, Zeppelin LZ-4 caught fire while moored
  1912, *Akron* explodes off Atlantic City
  1913, Zeppelin LZ-18 caught fire during test flight
  1915, Zeppelin L-4 burned when struck by lightning
  1915, SL-6 explodes after takeoff
  1915, Zeppelin L-18 burned in hangar
  1916, Zeppelin L-6 burned when being inflated
  1918, 4 Zeppelins and one other burned in mass hangar fire
  1918, Zeppelin L-59 explodes during flight
  1919, US Navy blimp C-8 explodes while landing
  1919, British blimp N.S.11 burned in flight
  1919, US blimp *Wingfoot Express* burned over Chicago
  1920, US Navy blimp D-1 burned at base
  1921, US Navy blimp C-3 burned at Hampton Roads, VA
  1921, British rigid airship R.38 broke in half and burned in mid-air
  1921, US Navy blimps D-6 and C-10 burned in hangar fire
  1922, US Army *Roma* struck power lines and burned
  1922, US Army blimp C-2 burned while exiting hangar
  1923, French Navy *Dixmude* struck by lightning and burned in flight
  1930, British rigid airship R.101 struck hillside during storm and burned
  1934 Soviet blimps V4, V5, and V7 all burned in a hangar fire
  1935, Soviet blimp V7-bis struck a powerline and burned
  1937, Zeppelin *Hindenburg* caught fire due to unknown cause and burned

  [0] https://en.wikipedia.org/wiki/List_of_airship_accidents
  [1] http://www.zeppelinhistory.com/zeppelin-facts/airship-accidents/

So less than one incident per year, most with a low amount of casualties, on what I assume was quite a big population of airships. And that is without modern technology, because we've made some progress in flame retardant materials

I find that rather makes the case of bringing back hydrogen filled airships.

> what I assume was quite a big population of airships

That might be a bad assumption. Hard to find numbers for all producers but based on the various lists of airships (links below), it looks like total number of airships produced was probably in the "few hundred" range, and only a small portion of those were in use at any given time.

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

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

https://en.wikipedia.org/wiki/List_of_Sch%C3%BCtte-Lanz_airs...

Looks like biggest risk the the hanger! One would hope we could avoid such risks with today's level of technology.

Geez, that documentary clip is really interesting. Given that lots and lots of incidiary and explosive rounds couldn't take down a Zeppelin, it really seems like the Hindenberg was really just an unfortunate one-off.

The Hindenberg had a ~ 60% survival rate. Plane crashes have close to 0% survivorship.

It shows the persistence of bad PR and the power of video.

Since autonomous airships still can still ignite as they're loading or unloading, it may be worth filling them with helium, but I do think using hydrogen may be more appropriate for Project Loon. Hydrogen could still be viable as long as the airship is designed so people won't be hurt even if it does ignite. For example, the cargo could be designed to have a low terminal velocity or a ballistic parachutes could be used.

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