Size of Dragon Hydrogen Bladders

[Hardy]

Yes, that's why the English still express body weight in units called "stones".

A remnant of an old unit. I can't argue with that. Metrication is a slow process, granted.

The problem is that metric is a foreign language to me - <snip>

Ah. I really can't blame you then. The educatonal system and the 70s culture would be more to blame.

Also, you're a pilot. From what I've experienced with American avaiation, metrication is seemingly impossible.

So when I "translate" there's always the possibility of my screwing up, just like those who don't speak English as a first language sometimes stumble over that. This transition has been made within the lifetimes of quite a number of people, and us old fogies are going to be at a disadvantage for the rest of our lives.

Hmm. I'm beginning to sympathize as most people over 35 that I know appear to have a problem with it. This makes me appreciative of being able to have denounced Imperial measurement in the eighth grade.

95.76 Newtons per square meter.

I'd like to mention that, due to being tired last night, I misplaced a decimel point. It's about 1 kg per .1 square meters. Does that affect the newtons? I'm not even sure what newtons are a measure of - wing loading is normally expressed as a unit of weight (the load) and a unit of area (what supports the load).

Well, your problem arises from "pounds" referring to both force and mass. Wing loading is, of course, measured as force over an area, not mass over an area. You simply don't measure force in kilograms. A Newton, as you can guess by its namesake, measures force and is a kg∙m/s². Since it's over an area, this becomes pressure and is known as a Pascal.
I'm sure you know the rest.

And, no. I directly converted your Imperial wing load stat instead of using your conversion. No trouble.

[Hardy]

Flying: Could it have a huge wing span and only glide? Or is a ton too large for this?

This applet was extremely helpful in approximating the shape and lift coefficient of a dragon's wing. A Cl of 2 is close.

So, according to the lift equation, if a 1000 kg dragon happens to be gliding at 30 m/s through normal sea level air with virtually no downward motion, it would need about 8.9 m² of wing surface area. It would correspond to a relatively short wingspan, depending on chord.

For gliding at a relatively slow (but seemingly realistic) speed of 10 m/s with minimal altitude loss, you'd need about 80 m² of wing area, which is comparable to the U2 Spy Plane.

[Master of Ossus]

If you're going around with hydrogen inside the BONES, then I imagine Helium would be a better pick since it's inert. Of course, the fact that it's inert and rare makes it almost impossible to find, but I don't really think it would be a good idea to be moving around with something that could react with oxygen to turn rather violently into water at any moment inside your tissues.

[wolveraptor]

i'd like to note that it was theorized by animal planet that dragons had super-strong muscles due to the increased O2 content of Cretaceous air (nearly 35% according to USGS, who studied air bubbles trapped in amber).

http://minerals.cr.usgs.gov/gips/0amber.htm

[Broomstick]

The problem is that metric is a foreign language to me - <snip>

Ah. I really can't blame you then. The educatonal system and the 70s culture would be more to blame.

Indeed. Knowing what I now know, if I had been given a choice I would have preferred to memorize all those constants of life like the acceleration under 1 g and so forth in metric. But the choice simply wasn't there - the only metric units I committed to memory in Chemistry and Physics class were those with no imperial equivalent.

Over time I acquired a "feel" for some units - after all yards and meters are nearly the same, as are quarts and liters. Kilometers and miles are farther apart, but knowing 100 km = 60 miles and 100 miles = 150 (very roughly) km will do for short distances and/or low speeds. But once I get outside of those familar units I can easily get lost.

It's not even as though I can immerse myself in the "foreign language" in daily life - to do so here in the American Midwest would be ridculous. Very little is sold in metric, outside (as I mentioned before) soda and illegal drugs (the latter being something I have nothing to do with). It would be like attempting to communicate in Greek.

Also, you're a pilot. From what I've experienced with American avaiation, metrication is seemingly impossible.

Very nearly.

I mean, yes, I could ask for the barometric pressure in millibars and at about half the airports I use I might even get it - but not one airplane I fly has an altimeter that's calibrated in millibars, they understand only inches of mercury. So, even if I did ask for and get millibars I might well find myself on final with an airplane in one hand and my flight computer in the other frantically trying to make a conversion - not exactly a safe proposition.

I mean, good heavens, two of the airplanes I've flown had airspeed gauges calibrated in miles per hour.

Actually, it's a nasty mess in US aviation - you can get information in almost any format. Some airports given temperature in Celcius and barometric pressure in inches - some will dispense Farenheit and millibars. It's crazy. It's why every cross country trip I bring TWO flight computers with me - the battery operated one with the computer chip inside for really precise work and the WWII era "whiz wheel" that doesn't require batteries and is just barely more advanced than an abacus.

Despite all that, we just had our safest year in aviation on record. Guess we're doing something right.

I have no idea how foreign pilots cope with this - no doubt the big airports and TRACONS will give information in metric, but the little airports...! You're lucky if they give you accurate winds and active runway in any units of measure. "Ayup... land so you're pointing east, away from the sun, and it's a pretty stiff breeze" No joke, I've gotten that. Ah, rural charm....

95.76 Newtons per square meter.

I'd like to mention that, due to being tired last night, I misplaced a decimel point. It's about 1 kg per .1 square meters. Does that affect the newtons? I'm not even sure what newtons are a measure of - wing loading is normally expressed as a unit of weight (the load) and a unit of area (what supports the load).

Well, your problem arises from "pounds" referring to both force and mass. Wing loading is, of course, measured as force over an area, not mass over an area. You simply don't measure force in kilograms. A Newton, as you can guess by its namesake, measures force and is a kg∙m/s². Since it's over an area, this becomes pressure and is known as a Pascal. I'm sure you know the rest.

Huh. IS it force? I thought it was average distribution of weight over a given area. 10 kg is supported on every square meter... is that force? Perhaps... never heard it referred to like that, don't know if it's confusion or just the use we pilots put it to, you know, the tendency to focus on the practical rather than the precisely correct under theory.

What I need to do is find some websites of airplane manufacturers and see if the wing loading is given in newtons or kg/m2 Just don't have the time tonight.

[Broomstick]

If you're going around with hydrogen inside the BONES, then I imagine Helium would be a better pick since it's inert. Of course, the fact that it's inert and rare makes it almost impossible to find, but I don't really think it would be a good idea to be moving around with something that could react with oxygen to turn rather violently into water at any moment inside your tissues.

Well, you're walking around right now with a quantity of hydrochloric acid inside you that's strong enough to dissolve iron - or your tooth enamel, as bulmics frequently discover the hard way. Strong enough to cause significant burns to tissues not adapted/protected from it.

This site, http://www.intuitor.com/moviephysics/ (Look under their entry for Reign of Fire - there's actually some pretty interesting reading there overall), has this to say in regards to flame producing dragons:

The idea of a biological system for emitting flame as a defense or attack mechanism is pretty incredible but, surprisingly, there's at least one real world example of something similar, although far less dramatic. The bombardier beetle has a defense mechanism for producing tiny explosions that blast a mixture of hot liquids in a would-be predator's face. These liquids can reach temperatures of 100 degrees C. The tiny explosions are created using a complex system for storing and eventually mixing hydroquinone and hydrogen peroxide with enzymes

So animals can produce and store some pretty nasty chemicals with minimal risk to themselves.

[Hardy]

I'm taking this measurement discussion to PM.

Huh. IS it force? I thought it was average distribution of weight over a given area. 10 kg is supported on every square meter... is that force?

Weight, is by definition, a measure of force. Wing loading should therefore be a measure of force over area, and not mass over area.

What I need to do is find some websites of airplane manufacturers and see if the wing loading is given in newtons or kg/m2 Just don't have the time tonight.

Both Cessna and Lockheed Martin use "kg/m²" as their unit of measure for wing loading. They're probably referring to kilogram-force which is 9.80665 N. Some sites I've found which aren't aircraft manufacturers use N/m² and Pascals to measure wing loading.

I think this settles the issue nicely:
http://www.aircraftdesign.com/metricwts.html

[Lord Zentei]

i'd like to note that it was theorized by animal planet that dragons had super-strong muscles due to the increased O2 content of Cretaceous air (nearly 35% according to USGS, who studied air bubbles trapped in amber).

http://minerals.cr.usgs.gov/gips/0amber.htm

If Dragons are supposed to have super strong muscles then why the hell are Animal Planet even mentioning the ridiculous hydrogen bladders nonsense? Incidentally, how will increased O2 content inevitably lead to stronger muscles?

Come to think of it, why are they including a programme on dragons at all?

[Master of Ossus]

Well, you're walking around right now with a quantity of hydrochloric acid inside you that's strong enough to dissolve iron - or your tooth enamel, as bulmics frequently discover the hard way. Strong enough to cause significant burns to tissues not adapted/protected from it.

While that's true, it's difficult to envision a scenario in which bone tissue can be shielded from oxygen while it's still in a living creature.

This site, http://www.intuitor.com/moviephysics/ (Look under their entry for Reign of Fire - there's actually some pretty interesting reading there overall), has this to say in regards to flame producing dragons:[snip]

Again, this is all true information but the use of Hydrogen in the dragon actually enables the thing to fly, and is supposed to permeate the thing's bones. It's much easier to set up dedicated organs for storing dangerous chemicals, but it's much harder to modify a bone so it can do the same thing. And, as others have pointed out, if the stuff were just for fire-breathing then it wouldn't make sense for there to be so much of it that the dragon couldn't fly without it.

[wolveraptor]

i'd like to note that it was theorized by animal planet that dragons had super-strong muscles due to the increased O2 content of Cretaceous air (nearly 35% according to USGS, who studied air bubbles trapped in amber).

http://minerals.cr.usgs.gov/gips/0amber.htm

If Dragons are supposed to have super strong muscles then why the hell are Animal Planet even mentioning the ridiculous hydrogen bladders nonsense? Incidentally, how will increased O2 content inevitably lead to stronger muscles?

Come to think of it, why are they including a programme on dragons at all?

Hydrogen bladders would be there to help the animals, i guess. and i just assumed (baselessly i suppose) that increased o2 content would provide more fuel for the muscles and respiration. I knowit would alleviate lactic acid conditions much quicker.

[Lord Zentei]

Hydrogen bladders would be there to help the animals, i guess. and i just assumed (baselessly i suppose) that increased o2 content would provide more fuel for the muscles and respiration. I knowit would alleviate lactic acid conditions much quicker.

As shown, hydrogen bladders would be a hinderance not a help. Strong muscles or gliding are the way to go if you want to get airborne.

For lactic acid you would need a decent blood circulation system, not O2 in the bones... and the chest muscles of flyers are white muscles for takeoff (white muscles = low bloodvessel count for high muscle fibre density.)

Bottom line: the Discovery channel and it's subchennels blow. They blow so much that it should be possible to sue them for it, and New Scientist magazine should be sued along with them. Watch the National Geographic channel and read Scientific American instead.

[General Brock]

AMX wrote: [Wrong]

And I keep fish and I know that. No more posting at 4:00 AM for me. Thanx for the kick.

[Broomstick]

Huh. IS it force? I thought it was average distribution of weight over a given area. 10 kg is supported on every square meter... is that force?

Weight, is by definition, a measure of force. Wing loading should therefore be a measure of force over area, and not mass over area.[/quote]
OK... but for better or worse, the convention among pilots is not newtons, but unit of weight/unite of area. At least in this country. And on a powerful lot of websites.

I wish I could come up with an appropriate anology, but it's been a long week and I'm tired enough to make hash of it if I tried.

Both Cessna and Lockheed Martin use "kg/m²" as their unit of measure for wing loading. They're probably referring to kilogram-force which is 9.80665 N. Some sites I've found which aren't aircraft manufacturers use N/m² and Pascals to measure wing loading.

That would be consistent with pilots using the kg/m2 or lbs/ft2 convention and the engineers using something technically more correct.

Wouldn't be the first time something like that happened. Way back in 1944 Wolfgang Langewiesche wrote about the difference between how pilots and aeronautical engineers regarded (and calculated) best glide.

Well, you're walking around right now with a quantity of hydrochloric acid inside you that's strong enough to dissolve iron - or your tooth enamel, as bulmics frequently discover the hard way. Strong enough to cause significant burns to tissues not adapted/protected from it.

While that's true, it's difficult to envision a scenario in which bone tissue can be shielded from oxygen while it's still in a living creature.

And why would that be necessary?

Again, this is all true information but the use of Hydrogen in the dragon actually enables the thing to fly, and is supposed to permeate the thing's bones. It's much easier to set up dedicated organs for storing dangerous chemicals, but it's much harder to modify a bone so it can do the same thing.

Is it? Birds already store air in their bones - seems to me it would be a matter of sealing off the compartments for better control of the gaseous content.

If you're going around with hydrogen inside the BONES, then I imagine Helium would be a better pick since it's inert. Of course, the fact that it's inert and rare makes it almost impossible to find, but I don't really think it would be a good idea to be moving around with something that could react with oxygen to turn rather violently into water at any moment inside your tissues.

While hydrogen is combustible, it's not so very combustible as all that. The Hindenburg, for example, flew enormous distances while supported with hydrogen and never had a problem. Interestingly enough, all the zepplins (if I recall correctly) of the time had gas bladders made of something called "goldbeater's skin" which is nothing more than the tanned lining of cow intestines. So hydrogren can co-exist quite nicely with organic tissues even in an atmosphere of 20% oxygen. Assuming gas bladders, hollow bones, or some other internal storage method, it's extremely unlikely such animals would spontaneously combust with any frequency. Oh, sure, the occassional lightning strike, but you don't need hydrogen storage to get killed by that. As a general rule, animals don't play with matches.

For that matter, oxygen is pretty hazardous, explosive, and corrosive yet your body manages it very nicely - would, in fact, expire without it.

The main argument against dragons, as far as I'm concerned, is that they wouldn't be able to fly in Earth conditions. Now, if you had a much denser atmosphere it would be far more feasible for such creatures to evolve. In fact, I think a denser atmosphere would be of more advantage in this instance than lower gravity. I mean, the Moon has less gravity than Earth but you can't glide at all there because there's no atmosphere to speak of. I also know from my own flying experience that a relatively small increase in atmospheric density can make a flying machine MUCH more effective/efficient. If you had a planet with a Venus-thick atmosphere but otherwise more compatible with life as we know it you probably could have a viable dragon-like critter.

[wolveraptor]

As shown, hydrogen bladders would be a hinderance not a help. Strong muscles or gliding are the way to go if you want to get airborne.

I'm guessing that for the space a hydrogen bladder takes up, it isn't as useful as pure muscular power.

For lactic acid you would need a decent blood circulation system, not O2 in the bones... and the chest muscles of flyers are white muscles for takeoff (white muscles = low bloodvessel count for high muscle fibre density.)

I don't recall mentioning O2 in the bones. In anycase, hollow bones would be a more advantageous system of respiration. I have no clue as to why, though. I just read it a while ago in Robert Bakker's Dinosaur Heresies. It would also lower the weight of the creature.
Also, lactic acid is produced by fast-twitch or white muscle fiber. A creature that could break up the acid faster would be able to recover from exertion quickly.

Bottom line: the Discovery channel and it's subchennels blow. They blow so much that it should be possible to sue them for it, and New Scientist magazine should be sued along with them. Watch the National Geographic channel and read Scientific American instead

Discover was cool in the old days, with Wild Discovery and stuff. Now it shows shit like Animal Face-off and Monster Garage. Discovery Science is stilll good though. They don't put up with crap.

As a side note, I've always gotten fuzzy reception with Nat Geo.

[Lord Zentei]

As shown, hydrogen bladders would be a hinderance not a help. Strong muscles or gliding are the way to go if you want to get airborne.

I'm guessing that for the space a hydrogen bladder takes up, it isn't as useful as pure muscular power.

Not to mention "less dragon like in appearance".

For lactic acid you would need a decent blood circulation system, not O2 in the bones... and the chest muscles of flyers are white muscles for takeoff (white muscles = low bloodvessel count for high muscle fibre density.)

I don't recall mentioning O2 in the bones. In anycase, hollow bones would be a more advantageous system of respiration. I have no clue as to why, though. I just read it a while ago in Robert Bakker's Dinosaur Heresies. It would also lower the weight of the creature.
Also, lactic acid is produced by fast-twitch or white muscle fiber. A creature that could break up the acid faster would be able to recover from exertion quickly.

Sorry about the bones bit, but you did mention 02. Oxyen needs to be stored by haemoglobin as it is being transported around the body, precicely because it is so reactive. Also, hollow bones are no good for respiration. Try a good pair of lungs instead.

PS: the oxygen is not fuel, it is the oxidiser. Food is fuel.

[wolveraptor]

referring to the hollow bone thing, Birds obviously have lungs, but i think the system inside their bones lets them absorb o2 more thoroughly. Don't remember a thing though, just that Robert Bakker wrote it.

Qt: why did O2 high periods in the past allow for huge creatures, such as massive insects and dinos? Wouldn't that be indicitave that it was a fuel...i think?

[Hardy]

OK... but for better or worse, the convention among pilots is not newtons, but unit of weight/unite of area. At least in this country. And on a powerful lot of websites.

A Newton is a valid unit to measure weight. Kilogram-Force must be simpler, I guess.

That would be consistent with pilots using the kg/m2 or lbs/ft2 convention and the engineers using something technically more correct.

Practicality versus accuracy, I guess.

The main argument against dragons, as far as I'm concerned, is that they wouldn't be able to fly in Earth conditions. Now, if you had a much denser atmosphere it would be far more feasible for such creatures to evolve.

True. A one ton dragon with a wing area of 25 m² (comparable to a WWII fighter) could modestly glide at 10 m/s if the air were only three times as dense.

[Broomstick]

referring to the hollow bone thing, Birds obviously have lungs, but i think the system inside their bones lets them absorb o2 more thoroughly. Don't remember a thing though, just that Robert Bakker wrote it.

Birds have a more complex respiratory system than any other group of animals, and it is connected to their hollow bones. It is for this reason that a species of goose is able to migrate over the peak of Mt. Everest, at an altitude of about 10,000 meters for several hours at a time. That's even more impressive when you realize that not only can many airplanes not reach that altitude, but no helicopter can. Birds are the only multi-celluar lifeform (other than man) to spend time at such altitudes, and they don't require supplemental oxygen even when engaged in strenuous activiy. It's not their hemoglobin that does it, rather it's their respiratory system. Very[/i] efficient.