Aircraft Stuff

[The Rock Doctor]

Thinking on aircraft a bit.  Here are some starting assumptions:

1)  The physics of aircraft remain valid.  There's no magic anti-aircraft decree across the world.

2)  The new world has access to historical data about Doolittle, Taranto, Midway, etc, just as it does about Jutland, Bismarck, and Iowa.

3)  The new world's cities are coastal or at sea; they are compact, with minimal land to spare for large airfields.  The area around an airfield would be city, with dire consequences if planes crash into them.

4)  The biosphere may have an airborne predator that is somewhat dangerous to slow, non-metal aircraft:  canvas and wood biplanes, airships, maybe helicopters.

5)  There may be an honor code that discourages strategic bombing of cities.

Thus:

-We expect that militaries will seek to use aircraft.

-They will also have defences against them - deck armor, dual-purpose guns, etc.

-Their aircraft will almost exclusively be ship-based or floatplanes.  Land-based aircraft may be possible - if somebody's willing to carve out the airstrips and endure the higher attrition rates caused by the local biota.

-Since it's easier to put a bunch of AA guns on ships than to build aircraft carriers, we'll probably find that, for a while, attackers can't generate a critical mass of aircraft necessary to overwhelm enemy AA defences.  For a while, we may see aircraft primarily used in scouting and ASW roles, with attack as a distinctly secondary function.

-Other than flying boats, we may not see development of multi-engined aircraft, with the implied loss of transport/attack capability implied.  Strategic air power may be a non-starter.

Thoughts?

[Nobody]

4)  The biosphere may have an airborne predator that is somewhat dangerous to slow, non-metal aircraft:  canvas and wood biplanes, airships, maybe helicopters.

I also thought of that. My conclusion was somewhat different though:
Airspace is dangerous (because of predators for example), so even when early light aircraft are build noone would dare to use them ,because they would be attacked almost immediately and most likely killed. But without previous examples/test, how would they ever get to sleek, fast all metal aircrafts? Certainly not impossible, but a really long way to go.

[The Rock Doctor]

It'd be possible to run a development program in some places.  Land-based air might be developed on isolated, sanitized islands (~Midway Island), or float-based air might be developed in marine areas with relatively calm waters.

Training air crew would be a challenge.  You would essentially be starting from scratch, with no existing pool of civilian aviators or outside infrastructure to make use of.  The graduated air crew would be pretty special - not something to throw away against hard targets with heavy AA defences...

[Carthaginian]

Hmmm...

I like this idea.
We would see a lot of aircraft cruisers, but not a lot of aircraft carriers... at least, not for 20+ years.
Lets run with it.

[The Rock Doctor]

Unless you've got these little islands to work with, I suspect it'd be easier to develop a training program for floatplanes than for wheeled planes.  After all, you only need a tender for a floatplane, whereas you need an aircraft carrier for the wheeled plane.

On that basis, you might see Tone-style cruisers used as scouting vessels, and your main strike platform might be a Commodore Teste-style seaplane carrier.  One might also find other large ships carrying a handful of seaplane-fighters for self-defence.  The Ise/Hyuga style hybrids might make sense, God help us all.

Of course, wheeled aircraft from proper carriers will still chew them up once fielded...

[Valles]

Speaking just for myself, I'd prefer to keep airships viable - solely out of cool factor, I admit.

Even that aside, I suspect that our interfering bird-analog is less of a roc or one of Alpha Shade's flyers, and more of a kind of sky piranha - aircraft don't get plucked out of the sky, they get mobbed. An airship can deal with this, by shutting the windows and using tough enough fabric for the outer envelope and so forth. Maybe ducted fans protected by screens. Airplanes... well, I think you probably could design one to cope, but it'd be tricky.

How the technologies would work out, I don't know. That's what the game's for, to find out!

[Carthaginian]

Uhm... there would be no fabric durable enough.
That's not how fabric works.

Kevlar can stop bullets... but not knives.
As the creatures would be focusing the cutting action of the bite on a point rather than an area, they would penetrate easier than a bullet. The metal in aircraft would be more suited to resisting the bites. Also, the higher speed of fixed-wing aircraft would make them more likely to be able to flee a natural predator which probably couldn't fly more than 100 m.p.h.

Additionally, in a place where land is at a premium, airships take more area than aircraft.

[Valles]

Claws and predatory beaks aren't knives, I note, but piercing weapons. 'Hard'-skinned airships are perfectly possible. And so on; the technical details aren't the substantive part of my previous post.

The thing that makes a swarm of killer songbirds dangerous to an aircraft, in my mind, isn't their attacks - it's the 'flew through a flock of geese' problem.

The amount of cleared area required for an air station, whether serving airships or airplanes, is not, IMHO, significant. It's not small, sure, but what makes farming difficult is the amount of territory required to feed a major population - You could only feed about seven thousand people off of O'Hare's area, for instance. This is big in human terms, but relative to the requirements of a nation of millions, it's peanuts.

[Carthaginian]

Claws and predatory beaks aren't knives, I note, but piercing weapons. 'Hard'-skinned airships are perfectly possible. And so on; the technical details aren't the substantive part of my previous post.

A knife, V, is a piercing weapon.
A slash doesn't go through kevlar easily (though it does cut it) but a stab will go through fairly easily.

A 'hard skinned' airship is not possible simply because of weight- airships depend upon lift from the envelope to get off the ground- make the envelope thick enough that it can withstand what you suggest and you have an envelope that is too heavy to fly!

The thing that makes a swarm of killer songbirds dangerous to an aircraft, in my mind, isn't their attacks - it's the 'flew through a flock of geese' problem.

OK- now we are getting somewhere!
If you make the airship sturdy enough that the aircraft 'deflects' impacts from this mass of medium-sized songbirds, you are going to get dramatically heavy rather quickly. Birds routinely dent cars and crack/shatter windshields. IF the envelope is flexible, they can kind of 'bounce off' and damage would be limited; if the envelope is stiff, then impact damage is magnified and starts to beat things against each other-leading to a larger chance of breakage. Now, if the bird can dent a car at 55 mph or shatter a windshield at 65 mph... what can a swarm of them do to an aircraft-thickness piece of aluminum at 110 mph? As you suggest- they would beat the ever-living shit out of it. Ducting the propellers wouldn't accomplish a thing, as the birds would still be getting chopped up, and the prop would still be getting damaged... because if you close the ducts, you are gonna loose control of your ship.

The amount of cleared area required for an air station, whether serving airships or airplanes, is not, IMHO, significant. It's not small, sure, but what makes farming difficult is the amount of territory required to feed a major population - You could only feed about seven thousand people off of O'Hare's area, for instance. This is big in human terms, but relative to the requirements of a nation of millions, it's peanuts.

Yes- but every time you build that structure, you remove the possibility to support another small city or large factory. That makes it very non-trivial in the grand scheme of things: "Do I build an airfield and give up the food for a cruiser squadron for a year?"

[Valles]

A knife, V, is a piercing weapon.
A slash doesn't go through kevlar easily (though it does cut it) but a stab will go through fairly easily.

Ah, yes. *facepalm* I think about swords too much.

A 'hard skinned' airship is not possible simply because of weight- airships depend upon lift from the envelope to get off the ground- make the envelope thick enough that it can withstand what you suggest and you have an envelope that is too heavy to fly!

So this is a hoax, then?

I've looked into the design of the thing a bit, and it looks to me like the envelope actually was of significant thickness - enough to take having a sparrow fly into it, at least, even if not with its own speed added.

OK- now we are getting somewhere!
If you make the airship sturdy enough that the aircraft 'deflects' impacts from this mass of medium-sized songbirds, you are going to get dramatically heavy rather quickly. Birds routinely dent cars and crack/shatter windshields. IF the envelope is flexible, they can kind of 'bounce off' and damage would be limited; if the envelope is stiff, then impact damage is magnified and starts to beat things against each other-leading to a larger chance of breakage. Now, if the bird can dent a car at 55 mph or shatter a windshield at 65 mph... what can a swarm of them do to an aircraft-thickness piece of aluminum at 110 mph? As you suggest- they would beat the ever-living shit out of it. Ducting the propellers wouldn't accomplish a thing, as the birds would still be getting chopped up, and the prop would still be getting damaged... because if you close the ducts, you are gonna loose control of your ship.

...Or you could just seal the ducts with mesh grilles finer than the size of your attackers, just like house fans. This would cut down on aerodynamic efficiency, but should protect the props.

Some quick googling turns up this site, whose immediately relevant datum is the suggestion that small birds are unlikely to bother going higher than a couple of thousand feet. Obviously it's possible that they'd continue an attack above that altitude, but IMHO it'd be unlikely for such a small organism to bother, instead just counting the intruder as 'driven off' and calling it good.

Airships, after all, don't have to remain constantly in forward motion - they can launch perfectly well by just casting loose and venting ballast until they drift up out of the danger zone, and maneuver at a walking pace if need be to land again.

Assuming that the call is made to have our killbirds perceive airships as 'intruders' rather than 'objects', the way they do airplanes. Sheer size might very well mean that they didn't. This'd be a GM call based on the desirability of having airships be common in the setting.

Personally, I'd be in favor - aside from the alternate-history cool factor, an airship is unlikely to make a successful air-attack platform against any target smaller than a city, and having them filling the 'airborne scouting' niche would further delay the development of the airplane and accordingly prolong the battleship era.

Yes- but every time you build that structure, you remove the possibility to support another small city or large factory. That makes it very non-trivial in the grand scheme of things: "Do I build an airfield and give up the food for a cruiser squadron for a year?"

Of course it's a serious question! But it's not an absolute game-breaker the way you seemed to be implying.

[The Rock Doctor]

Alright, so that's something to mull over.  Let's park that issue for the moment...

[Nobody]

Lets imagine some nasty flying animals here*. To be a threat to aircrafts they would have to be (at least some of them) the size of small aircrafts. But how would people in the cities on the ground be safe? Maybe they just don't like confined spaces like streets? Fields could be covered by wire nets.
Airships or Zeppelins, they are HUGE. Maybe just big enough to be attacked by those nasty bird?

About the metal/hard skip airship: it's hull has had a maximun thickness of only 0.24 mm (0.0095"). Not really going to stop anything. It would also loose its shape should the internal pressure drop.

Oh and isn't it time to move the "air" stuff in it's own section as well?

*)trying very hard not to think of dragons... although there should be enough big birds, flying Dinosaurs and meter-sized fireflies etc.

[Carthaginian]

A knife, V, is a piercing weapon.
A slash doesn't go through kevlar easily (though it does cut it) but a stab will go through fairly easily.

Ah, yes. *facepalm* I think about swords too much.

Nothing wrong with that!

Yes- but every time you build that structure, you remove the possibility to support another small city or large factory. That makes it very non-trivial in the grand scheme of things: "Do I build an airfield and give up the food for a cruiser squadron for a year?"

Of course it's a serious question! But it's not an absolute game-breaker the way you seemed to be implying.

Meh- I just looked at it as it was... the choice between having an airbase of planes likely to get eat, or the chance to field a bakers dozen Tone class aircraft cruisers. It's not really a game breaker by any means; it was just something to think about in-character.

[The Rock Doctor]

I don't think I have the ability to move the air stuff into a new thread - maybe Mike could do that?

[Valles]

Lets imagine some nasty flying animals here*. To be a threat to aircrafts they would have to be (at least some of them) the size of small aircrafts. But how would people in the cities on the ground be safe? Maybe they just don't like confined spaces like streets? Fields could be covered by wire nets.
Airships or Zeppelins, they are HUGE. Maybe just big enough to be attacked by those nasty bird?

About the metal/hard skip airship: it's hull has had a maximun thickness of only 0.24 mm (0.0095"). Not really going to stop anything. It would also loose its shape should the internal pressure drop.

Oh and isn't it time to move the "air" stuff in it's own section as well?

*)trying very hard not to think of dragons... although there should be enough big birds, flying Dinosaurs and meter-sized fireflies etc.

Suddenly, I'm flashing back...

I'd read the description of the method of construction as implying multiple layers of the hull-metal, actually. Could be wrong on that.

Any case, although the flyers are awesome, I don't think that a species that large is really plausible - hence my suggestion of the hazard's being more by way of a 'willing birdstrike' issue than actual hunting.