...and let the smutty jokes commence!
NASA got a great big balloon for the 75th anniversary of its iconic Moffett airfield in the heart of Silicon Valley. The space agency on Friday celebrated the landmark occasion with the dedication of the world's largest airship, a 246-foot Zeppelin owned by the private company Airship Ventures. The lighter-than-air craft …
Ah, the myth about hydrogen being the cause of a certain disaster...never put facts before a good story (or myth)...
...the bit I really liked is where they got the now classic, "it's an ideal thing to monitor the environment"...
...apparently you can get away with anything (except environmentally friendly anything with nuclear or atom in its name) if you state something like,"for environmental reasons..."
IN saying all that, I wouldn't mind a Zeppelin myself...beats queuing at rush hour!
"airship flight back home where it belongs."
Not Lakenhurst, New Jersey then where most US airship activity took place.
Let alone a mention of Friedrichshafen where it all begins.
Or Howden, Pulham (and later Cardington) where UK activities too place.
Mine's the one with the silk outer and rubber pockets.
"The craft is one of only three Zeppelins currently in operation in the world. It's also the first to touch down on US soil since the ill-fated Hindenburg crashed in 1937. Of course, Eureka is filled with helium, a considerably less "Oh, the humanity!" combustible gas than hydrogen.
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Don't you just love these!
How is that NASA thing different this I was lucky enough to have a flight in in over last Xmas operating out of Florida business airport for family and friends..
This comes with a built on TV !
Great fun :-)
"...apparently you can get away with anything (except environmentally friendly anything with nuclear or atom in its name) if you state something like,'for environmental reasons...'"
Exactly what part of "radioactive waste", which can be highly radioactive for hundreds of thousands of years (source: US NRC [www.nrc.gov]), is environmentally friendly? And, if it *IS* determined to be "environmentally" friendly, radioactive waste isn't exactly PEOPLE-friendly, now is it?
The Hindenburg burned because the coating on the canvas was powdered aluminum and varnish, which is similar in composition to solid rocket fuel. This is what caught on fire from electrical discharge. Most of the casualties were from people panicking and jumping out of the airship from 100ft. Of the people who stayed on the ship until it was on the ground, six of the crew died from diesel fuel burns.
Hydrogen does not combust in an airship -- it escapes into the atmosphere because it is the lightest element. Once the bag is punctured, the hydrogen is long gone.
re: "Once the bag is punctured, the hydrogen is long gone."
Not quite; the Hindenburg was a rigid airship (you can see the metal frame collapsing in the newsreels of the disaster as it hit the deck) and the hydrogen was only at a slightly positive pressure, so unless it was punctured both at top and bottom, the hydrogen wouldn't go anywhere fast, unless it ignited at the air/gas interface then it would quickly burn the envelope and free more gas, which would burn the envelope and free more gas...etc. That is what we see on the newsreel.
The flammability of the envelope may have contributed to the fire, but other hydrogen filled airships (and ballons) also went up in flames, albeit less publicly, whereas I can't recall any helium filled aircraft doing the same.
What no one has pointed out yet, is that airships are useless in bad weather. With a top speed of 35mph, anything above a 36mph headwind will see it going backwards, and airships can't tack like a sail boat (no keel and a huge wind-catching side profile) I watched a Virgin Lightship try it once; every time it turned its nose slightly out of the wind it shot backwards pushing the tail downwards towards the ground - very dangerous. More airships have been lost through bad weather than fire.
And you clearly never let a good bit of Chemistry and Physics get in the way of trying to feel supirior.
"Ah, the myth about hydrogen being the cause of a certain disaster...never put facts before a good story (or myth)..."
You mean the THEORY that it was not the Hydrogen? So now your theory is more valid than other peoples theorys? Oh, of course, your a climat change denier....
"Hydrogen does not combust in an airship -- it escapes into the atmosphere because it is the lightest element. Once the bag is punctured, the hydrogen is long gone."
That makes no sense at all.... Clearly the Hydrogen did not escape as the Hindenburg was very still floating when it started to burn. Claming it escaped is just a stupid thing to say.
*waits for angry replys that try to make my comment worthless by doing nothing more than pick my spelling to pieces*
I don't think that Brian Miller put his point across very well, but the point remains: put your hydrogen inside a certified, non-flammable skin and you will be an awful lot safer than the Hindenburg was.
As with all gases, an explosion will only occur if it is well mixed with an oxidiser, or oxygen itself - you don't see much fuss about the tanks full of liquid hydrogen that are common to most space-rockets, do you?
The thing that really hacks me off is the way that people have been quoting the Hindenburg 'disaster' as the justification for ignoring airship technology for the last 70 years. Let's at least acknowledge that even with that (now completely obsolete) hydrogen/canvas technology, two thirds of the passengers survived, which is a d*mn sight better than most modern airliners can manage when they seriously prang on landing/meet an unexpected hillside/impact a skyscraper. Given that even a punctured helium/semi-rigid Zeppelin stands at least a chance of just gently losing pressure and coming to ground, which would you rather be in?
For that much cash, I'd hope for a passenger compartment that was purpose built to give me a big field of view. Why are the seats facing forward? Why don't the windows go down to floor level? Why is the floor opaque?
I can understand all these things in a plane or bus, but not in a zeppelin.
Acherly, hydrogen burns with a non-luminous flame. For the non-cognoscenti, this means that the heat goes up, not out. I've actually witnessed this at (too) close hand. You can get burned on a hydrogen flame because by the time you feel it, you are in it. It is too dim to see in daylight, and gives off tiny amounts of radiant heat to the sides.
The newsreel footage of Hindenberg burning clearly show the luminous nature of the flame. Whatever is burning there, it most certainly isn't the hydrogen.
Of course, one could argue that although filling the Hindenburg with helium would not have prevented the fire itself (it wouldn't, the Mythbusters groundbreaking "experiments" notwithstanding) it might have acted in a fire suppressant mode to contain the disaster. This might be worth modelling to see what's what.
While "pure" hydrogen may burn with a near colourless flame, any flame will be coloured by other oxidisables within it. That "orange" colour does not preclude a hydrogen flame with other compounds being oxidised inside it. In fact, while, as has been said, it would be unlikely to explode, the gas escaping from the gasbags would be hard-pressed to avoid ignition, if there was a naked flame about; there would be plenty of air to mix with it and convection currents about to do the mixing, even if the Hydrogen just added to existing fires.
I don't think anyone has ever claimed the hydrogen just vanished without interacting with the fire that probably started in the envelope material.
I visited the Zeppelin Museum in Friedrichshafen this year and I can highly recommend it.
I had no idea that the US even had airships like the USS Macon, which actually acted as an aircraft carrier, launching propellor-driven planes by dropping them out the bottom.
There's also a great big partial reconstruction of the Hindenburg which you can go inside. Very swish.
I actually only went there because I was going to Germany (and nearby Switzerland) and Friedrichshafen's tiny airport happens to be a Ryanair destination, but it was well worth a visit.
While I agree that the Hindenburg passengers did indeed get of lightly (because the burning gas went *up*, and being heated went up damn fast), the history of the rigid airship is far from rosy even if you don't count the Hindenburg.
The big problem with airships is that they need to constantly fight the changing air pressure that weather brings on, with resulting changes in airship bouyancy in parts of the airframe. The stresses set up by adverse weather can wreak havoc with the lightweight frame of an airship, especially given the immense amount of leverage that is available over the length of the thing. Both the R38 and the USS Shenandoah snapped in two as a result of weather-induced stresses.
Don't get me wrong: I'd love to see these things in the air again. Perhaps with modern computer sensing and control and composite materials it might even be viable. Even with Helium (which is problematical in that the lift available from it makes for very poor airframe volume/passenger ratio) the case for them is poor.
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