[Worldwalker]

Well, this guy's got a zeppelin.

I haven't been able to endure enough of the excerpt to find out if there's anything in there about the way they built it, but historically, the two necessary technologies were the Hall-Herault process and the internal combustion engine -- the former to produce aluminum for the frame, the latter to produce motors with an adequate power to weight ratio for lighter-than-air craft. Both of those postdate the Civil War considerably.

Without aluminum, or better yet aluminum/copper alloys, it's going to be nearly impossible to produce a rigid airframe that is light enough to get off the ground. Something like a spruce skeleton with bamboo spars might be light enough to fly, though it would cut into the payload capacity drastically, but would it be able to remain rigid enough? Rigidity is essential; a wiggly zeppelin will tear itself apart.

Power is another problem. While early internal combustion engines existed, they were extremely heavy and low-powered. An engine adequate to power a farm tractor just isn't sufficient for aviation use. One of the biggest, if not the biggest, threats to the zeppelins that bombed England in WWI was the weather. Their motors were not powerful enough to fly against strong winds, so many were blown off course and crashed. It's hard to envision what the Confederacy could have produced which could perform as well as what a country noted for its technology had 50 years later. Again, engine weight cuts into your payload capacity.

There's also fuel for those motors. Again, we're looking at power and weight, and nothing that would have been available to the Confederacy would have an energy density anywhere close to petroleum products. The Texas oil fields were still years in the future; oil was a northern resource. Alcohol would really be the only alternative, but you have to carry a lot more of it, and feed a lot bigger engine, for the same power output. Never mind payload capacity, the question of whether this thing can even get off the ground is becoming critical.

What are the gas cells made of? Historically, zeppelins used a form of parchment made from the intestines of cattle, called goldbeater's skin because it was used in the making of gold leaf. It's strong, flexible, and light -- and enough to build a single zeppelin requires the guts of tens of thousands of cattle, and the requisite production facilities. The more likely alternative would be doped silk, which is not nearly as light and leaks hydrogen like a sieve.

Would it even be hydrogen? Or would it be illuminating gas (coal gas)? If the latter, we've lost even more lifting capacity; if the former, there's the problem of keeping it in that silk envelope for long periods of time.

There's also the question of the effectiveness of said dirigibles in warfare.

For observation, yes, they'd be handy, but whether they'd be enormously more useful than fixed balloons is another matter entirely, especially since a tethered balloon could supply observations in realtime via telegraph, while a dirigible would be limited to dropped messages. They might actually be more effective as portable balloons, traveling to where they were needed and dropping a tether/telegraph line to a ground crew.

Bombing, on the other hand, would only work as a terror weapon, if that. Again, look at the WWI zeppelin raids. They were doing well to hit the right city. If they flew low enough to have any accuracy whatsoever, someone shot them full of holes, which is a bad thing when you're flying around with a ginormous bag of explosive gas. Precision bombing was a concept yet to come. Now go back 50 years. No TNT, no Lyddite, not even dynamite. The only practical explosive was black powder. The amount of damage that could be done against an industrial target -- say, a shipyard -- would be fairly low, even if the zeppelin could actually hit the thing. The resources required to repair the damage would be a fraction of the resources required to inflict the damage, and the Union had more reserve industrial capacity than the Confederacy.

The technical limitations of this zeppelin would probably limit to operating at much lower altitudes than its real brethren 50 years in the future. Wind shear could tear it apart in seconds. If that brought it within range of Union sharpshooters, well, a giant flying gasbag is a pretty good target. Nobody had invented incendiary bullets yet (possibly because they didn't have much of a need for them) but a few rips in the gas cells could be enough to disable it. It's going to have gas pressure issues to begin with -- remember how well silk doesn't hold hydrogen.

The technologies required to produce an effective military zeppelin include the mass production of aluminum, lightweight internal combustion engines, petroleum production and distillation to fuel those engines, and either an effective high explosive for bombing or a means of long-range communication for observation. Resources required include fuel, goldbeater's skin, and lifting gas. It's going to take a lot to convince me that these, or any effective substitutes for the, would be available to a primarily agricultural country half a century before they were employed by a heavily industrialized country.

Maybe this author has explanations for where the Confederacy would get these things, or what they would substitute for them. I guess I'll never know, because I simply can't plow through enough of his book to find out.

A lot of amateur writers (and a disturbing number of professional ones) forget that no invention, no technology, exists in isolation. There are necessary precursors, there are supporting technologies, there are spin-offs ... there's a whole structure required. And there, I suspect, this author has failed as well.