Colombian Not-To-Be Ships

Started by The Rock Doctor, August 13, 2010, 06:41:13 PM

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Carthaginian

With 8-12 heavy MG's, that is still not likely to do enough damage to make it dangerous.

Sorry, I'm a guy who's run a heavy MG (M2 .50BMG) and large caliber automatic grenade (Mk 19 40mm) launcher in real life. They are dangerous, but not all powerful.
So 'ere's to you, Fuzzy-Wuzzy, at your 'ome in old Baghdad;
You're a pore benighted 'eathen but a first-class fightin' man;
We gives you your certificate, an' if you want it signed
We'll come an' 'ave a romp with you whenever you're inclined.

damocles

#31
Quote from: Carthaginian on August 16, 2010, 05:45:46 AM
With 8-12 heavy MG's, that is still not likely to do enough damage to make it dangerous.

Sorry, I'm a guy who's run a heavy MG (M2 .50BMG) and large caliber automatic grenade (Mk 19 40mm) launcher in real life. They are dangerous, but not all powerful.

I am not that familiar with the fall trajectory arc of the M-19 but I was under the impression that it was a low velocity weapon that was not a true HV auto-cannon, but that it was more like a mortar?  

Zeppelins historically are very fragile. A pair of machine guns can kill them. Or something as simple as a lighted cigarette. (The dope used to air seal the gas bags in most cases was highly flammable. Or just wind blown debris could or climb to excessive altitude. I refer you to the Shenandoah disaster.

http://www.airships.net/us-navy-rigid-airships/uss-shenandoah

OOC
Which is a problem that I think the French will soon discover. There is an IC reason the Dutch rejected the airship in favor of the plane. I will publish a story about cell inflation and the failure to punch through the 7000 meter ceiling.

maddox

I beg to differ.
Rigid airships  have a remarkable damage tolerance if it comes to pure physical damage. And the hydrogen flamability issue was solved  early 1920's, as about every large airship designed for hydrogen proves. LZ127 and R100 come to mind.
Of course, LZ 129 Hindenburg did burst into flames. But it was never ment to be filled with hydrogen, wasn't it.

And yes, showering an airship with tracers or incendiary shells will put it aflame. But not as easy as most people think.

damocles

1. The chief design failure of rigid airships was that their frame strength was inadequate to take torque or bend loads.
2. They could not fly in thunderstorms or simple wind-shear, ever.
3. The loss rate > 50% per 1000 hours flight was appalling.
4. Riddle the nose full of simple simple bullet holes and tears and watch it SNAP in two as the nose falls and the tail lifts. You don't have to set it on fire at all to cause a bend moment that it cannot sustain.
5.

http://www.youtube.com/watch?v=F54rqDh2mWA

The hydrogen problem was never solved.   
 

maddox

Quote from: damocles on August 16, 2010, 08:30:34 AM
1. The chief design failure of rigid airships was that their frame strength was inadequate to take torque or bend loads.
Especialy true with the German High Flyer designs, and there is the rub, the first UK rigids after WWI took the design of such one.

Quote2. They could not fly in thunderstorms or simple wind-shear, ever.
What aircraft could in those years? Or, compare that as a weakness to the avarage tramp on the 7 seas.
Quote3. The loss rate > 50% per 1000 hours flight was appalling.
Compare that to the loss rate of commercial flights with aircraft.

Quote4. Riddle the nose full of simple simple bullet holes and tears and watch it SNAP in two as the nose falls and the tail lifts. You don't have to set it on fire at all to cause a bend moment that it cannot sustain.
Riddle anything with bulletholes and watch it break.

QuoteThe hydrogen problem was never solved.
That's why Graf Zeppelin blew up.... Oh, it didn't. 
Flamability and such are technical problems, and have technical solutions. The main reason everybody believes airships filled with hydrogen are floating bombs is LZ129 Hindenburg, an airship designed to use Helium as liftgas, and therefor, never had the extra technological tricks LZ 127Graf Zeppelin used.   
 

Valles

There's also the factor that, at this point in time, a large payload for an airship is thirty tons, while a large payload for an airplane is a quarter of a ton.

I submit to you, sir, that this is a not inconsiderable difference.
======================================================

When the mother ship's cannon cracked the signal to return
The clouds were building bastions in the swirling up above
Poseidon the King and the Wind his jester
Dancing with the Lightning Lady Fair
Dancing with the Lightning Lady Fair

damocles

Quote from: maddox on August 16, 2010, 09:59:49 AM
Quote from: damocles on August 16, 2010, 08:30:34 AM
1. The chief design failure of rigid airships was that their frame strength was inadequate to take torque or bend loads.
Especialy true with the German High Flyer designs, and there is the rub, the first UK rigids after WWI took the design of such one.

Note that even in 1939 the Germans scrupulously tried to avoid wind sheer and thunderstorms?

Quote2. They could not fly in thunderstorms or simple wind-shear, ever.
What aircraft could in those years? Or, compare that as a weakness to the avarage tramp on the 7 seas.

Fokker D-VII
Curtis JN-IV series
Spads


Quote3. The loss rate > 50% per 1000 hours flight was appalling.
Compare that to the loss rate of commercial flights with aircraft.

The commercial loss rate of aircraft of the JN IV-D was appalling (similar), but note that you lost three men and a $1700 plane. With a Zep, it was usually a score of men and $100,000 on up.

Quote4. Riddle the nose full of simple simple bullet holes and tears and watch it SNAP in two as the nose falls and the tail lifts. You don't have to set it on fire at all to cause a bend moment that it cannot sustain.
Riddle anything with bulletholes and watch it break.

Same JN-IV was bullet resistant. Tough plane. Cost a lot less than a Zep, too.


QuoteThe hydrogen problem was never solved.
That's why Graf Zeppelin blew up.... Oh, it didn't. 
Flamability and such are technical problems, and have technical solutions. The main reason everybody believes airships filled with hydrogen are floating bombs is LZ129 Hindenburg, an airship designed to use Helium as liftgas, and therefor, never had the extra technological tricks LZ 127Graf Zeppelin used.   
The Akron and the Macon were both designed as helium Zeps. Both crashed. They had the tricks the Germans used in the Hindenberg. As for the Hindenburg....

http://mythbustersresults.com/episode70


It was too bad that the prople who built her used a thermite dope as a gas seal.


Nobody

I have never heard of Graf Zeppelin having any special equipment that Hindenburg (or Graf Zeppelin II) did not have, but it sounds reasonable.

Zeppelins are not as fragile as they look like, a storm is not a problem for them - unless they are close to the ground. Most if not all Zeppelins were lost during landing/starting, while being anchored or if put in/out their hangar.





P.S.:
I had the chance to fly with the Zeppelin NT this month - a remarkable experience.

TexanCowboy

Frankly, that's a ridiciolus argument. No sane pilot is going to take a WWI era plane or airship up in a thunderstorm....it may be technically possible, but a pilot in an open cockpit isn't going to do that sort of stupid thing. Ever wonder why flight operations, up to around WWII, were simply not possible in heavy weather, and why commercial flights today still refuse to fly though heavy thunderstorms, and will cancel flights because of them? There was no IFRs back then, so it would be impossible...just saying.

Maybe the Jenny is a lot more resistant then a Zep, to bullets, but it's a lot easier to wipe out a Jenny with a pilot kill then it is with a Zep, in a cabin.....besides, it would take a lot of bullet holes to blow up a Zeppie, without stuff like Le Prier rockets and Incendiary ammunition....which, for the former, is inaccurate, and used by me and Walter already (and failing epically, I might add), and for the latter, not commonly used....aircraft and airships are still competing, as compared to OTL when airplanes were already dominant by this point.

The Akron and the Macon were lost to weather, so that's uncomparable.

damocles

Like most aircraft, a Zep has to be trimmed for load over the length of the vehicle. Loss of the American Zeps was usually as a result of frame failure when the load force limits were exceeded.  

Something set the Hindenberg on fire. Lightning is the usual claimed culprit.

http://www.youtube.com/watch?v=hXjVxOGCEpQ

http://www.youtube.com/watch?v=Week2XRWLYs&feature=related

I think that shows the disaster is well researched. Hydrogen was the known fuel, oxygen the oxidizer. The ignition agent is what in dispute.  

Hydrogen burns, it does not explode in the air medium. It has to be confined to "explode".

http://en.wikipedia.org/wiki/Air_Mail_scandal

The Americans did fly in the type weather described using the inferior DH-IV. 

Desertfox

No sane pilot EVER will fly a plane knowingly through a thunderstorm. The loads will tear apart ANY plane. I've been in enough of them to know that even driving is dangerous.

Yes the USAAC flew the mail in all weather, it also resulted in half the pilots being killed in the first month.

A well designed zep is a safe ship. See Los Angeles and Graf Zeppelin. Macon was lost to a design flaw and poor damage control afterward. Akron and Shenandoah where lost to really bad weather. But even then see Shenandoah, ripped into three pieces all of which landed safely. Plenty of WWI zeps where riddled with holes and made it home safe.
"We don't run from the end of the world. We CHARGE!" Schlock

http://www.schlockmercenary.com/d/20090102.html

Valles

QuoteNote that even in 1939 the Germans scrupulously tried to avoid wind sheer and thunderstorms? 

This is what is known as 'responsible flying'. Hell, responsible behavior full stop.

QuoteThe commercial loss rate of aircraft of the JN IV-D was appalling (similar), but note that you lost three men and a $1700 plane. With a Zep, it was usually a score of men and $100,000 on up. 

For a national fleet, the individual price tag is only a matter of publicity. Whether you lost that percentage of your operations in downing sixty biplanes or one airship, the totals come out the same.

QuoteThe Akron and the Macon were both designed as helium Zeps. Both crashed. They had the tricks the Germans used in the Hindenberg. As for the Hindenburg....

http://mythbustersresults.com/episode70

It was too bad that the people who built her used a thermite dope as a gas seal.

If you're going to pick at a weakness, please try not to confuse it with others. Waffling back and forth between whatever suits your purpose does your credibility no favors, and thus your argument notable harm. Are you concerned about flammability, or about storms?

Further, the assumption that every airship in Nverse is built after the model of the classic Zeppelins is mistaken; I've known for some time that Maori 'liftships' used semi-monocoque hulls with lightly-waterproofed balsa shells over sparse duraluminum skeletons. Flammable, yes, but hardly the same kind of rocket fuel that was used for many thousands of hours of safe flight. The outer shell is heavier, that way - though I think not by as much as many people would assume - but the skeleton can be built lighter and using a stronger arrangement since the mechanical properties of the shell mean there'd be no need to worry about its effects on drag. The biggest problem the Maori face is wetness and rot, and that's addressable by proper attention to sealant and hanger maintenance.
======================================================

When the mother ship's cannon cracked the signal to return
The clouds were building bastions in the swirling up above
Poseidon the King and the Wind his jester
Dancing with the Lightning Lady Fair
Dancing with the Lightning Lady Fair

maddox

Valles, you have a point with your Balsa Clad. The ZMC-2 is another , later example of that way of building.

P3D

Balsa sheets might not be the best idea. Waterproofing will weight more than the sheet itself. Sandwich plies would also add more weight.
Balsa lightness is good for rigidity, but for airship shell I'd choose the flexibility and Strength of Aluminum.

BTW what was the Al skin thickness for the Zeppelins?
The first purpose of a warship is to remain afloat. Anon.
Below 40 degrees, there is no law. Below 50 degrees, there is no God. sailor's maxim on weather in the Southern seas

Valles

The original reason for adopting that design approach is artistic/meta; the treated wood is yellow-blond, visually very distinctive from the standard doped-canvas silver-grey of the classic rigid airship. In-character, it was picked up before it was clear that aluminum sheeting was even possible at such a scale, and kept because its properties are well understood and continually being pushed. The outer shell is already laminated - formed of crisscrossing strips in three layers or so - but the only loads it's intended to bear are aerodynamic and local; the stress-bearing structure is a geodesic arrangement of duralumin girders. As far as I can tell, the only assumption that's really required in the entire matter is that a suitable lightweight sealant could be found, and I don't think that that's a stretch.
======================================================

When the mother ship's cannon cracked the signal to return
The clouds were building bastions in the swirling up above
Poseidon the King and the Wind his jester
Dancing with the Lightning Lady Fair
Dancing with the Lightning Lady Fair