In the 19th century, LTA aviation will be quite competitive in the sense that it will be as tantalizingly close to seeming attainable as aerodynamic flight. And also will fall short of the goals, for the same reasons HTA does.
Of course the difference is, the way HTA fails at this point is to completely fail to achieve sustainable flight at all, whereas ballooning was in the presumably unbutterflied past of the late 18th and early 19th century already achieved, and even after the POD I would expect the OTL efforts of the 19th century airship pioneers to be carried over, either by alt-timeline "brother/cousins" of the same people of OTL, or by completely different people attempting things the ITTL counterparts of the people of OTL leave undone because they have different interests or fail to exist at all!
I'd have to revisit the history of OTL to be definitive, but I believe at this point OTL, electric-powered dirigibles have flown as have steam-powered ones.
The problem is, the available power plants don't have the necessary power to weight ratios to deliver what is needed to maintain a steady course in the face of uncooperative winds. Also, everyone has rather primitive and confused ideas of how aerodynamics works and so in retrospect most of the OTL airship designs are appallingly draggy. There are structural issues too, which tend to favor poorer aerodynamics (the same was true of early airplanes OTL of course).
The same advancing tech that made airplanes possible and then practical was needed to enable really functional airships worthy of the name. I'm not sure why or how I got the impression that technology would advance faster in this timeline, but that dream has confused me regarding it before. I'd like it to happen just because more people are being included as closer to equals in the European-based global technical-capitalist society, but realistically I don't suppose that will greatly accelerate progress. A little bit, not much.
So, put it this way--suppose we had the world of OTL, forget about West Africa and the likelihood that the Islamic world in general will be more robust and less wracked with turmoil (at least, the turmoil will lead to more progress sooner one hopes) here; just look at the European powers (and the USA, and counting Russia as a European power of course--the Russians made quite a few major contributions to science and bids for glory in advanced tech OTL long before the Bolsheviks took over there) and ask yourself, if all the major leaders of the European nations--not just political leaders but owners of major industries--had had some premonition they'd be at war before the decade was out in 1890, what sort of aviation could they have come up with?
Probably all various kinds of dirigibles, and none of them of very impressive performance--though certainly having some kind of aircraft is way more impressive than having none! To have any sort of airplane actually flying, we need to preempt the work of the Wright Brothers by more than a decade. Now off the top of my head, I'm not aware of any materials or off-the-shelf machinery the brothers had available in 1904 that wouldn't have had close equivalents in 1894 (but we need it earlier so that there is some time for practical development and for war planners to include them in their plans, so say 1884). The Wrights did their own aerodynamic research; they went back to square one, built their own wind tunnels, worked out their own theories of lift and from them derived a uniquely advanced propeller design, and I believe made their own gasoline engine too for their purposes. Could all this have happened 15 or 20 years before?
Well, I doubt it, because I suppose that there were indeed materials available in '04 that wouldn't have been in '84 or even 1890; because although they made their own gasoline engine they doubtless studied existing ones and there would have been far fewer or none earlier and none as good as the examples the Wrights or their competitors had available to inspire, guide and warn them in the 20th century; although they took a fresh look at aerodynamic theory, they did so while avidly studying both academic theory as it came available to them and the practical data of many attempts by many people to achieve powered flight, plus intensive study of gliding flight by people like Octave Chanute.
If Jonathan were moved to have it so, there's room for saying "oh yes, people were more air-minded earlier, though it hasn't come up as a relevant subject yet" and therefore there would be more grist of trials that erred for these alternate aspiring aeronauts to mill. But they still wouldn't have adequate engines unless that field of invention were also more advanced, and with it metallurgy, and so on. I tend to think that technology is a web where it's hard to advance one part of it without advancing everything more or less in step. There's no obvious reason why anyone anywhere in this timeline would be either more motivated or have better opportunity to be much more advanced in any field (except perhaps tropical agronomy and epidemiology) than OTL.
So, sadly, no airplanes. Not unless someone is so desperate to fly they devise some kind of long-burning rocket to drive a glider up to a height from which it can then glide down, which is sort of an airplane. That requires someone to be a whiz at making reliable solid fuel rockets that don't explode (or set the presumably very lightweight glider structure on fire) and might not be any more plausible really than advancing the IC engine by a decade or more.
Actually this rocket-glider notion came up in WI threads about the plausibility of really ancient aircraft, like Tang dynasty China or medieval Europe, and I thought it was possibly doable (with a lot of trial and tragic error!) and would seem cool enough and marginally useful enough to be kept in practice. For stuff like scouting for army maneuvers, possibly for ships. Presumably the pilot is a good swimmer and the glider is expendable, or the tech gets good enough to enable a skillful pilot to land on the water to be winched back up aboard ship, in good enough weather anyway.
But OTL no one did such a wacky thing unless one believes some accounts from ancient China.
Nope, I think we are looking at dirigibles here, and not very big ones, and not very dirigible except in very calm weather. Very vulnerable to enemy gun fire. Well, actually hydrogen lifted airships were a bit tougher under fire than one might think, but since one might think they'd go up in flames at the first shot--not actually true, more often than not--the fact was over land they were generally abandoned, at least on the Western Front of WWI--I believe the Germans and also the Russians kept using airships in the East quite a lont time. But we aren't talking Zeppelins here, not even the clunky kind they had in 1914; those would be awesomely futuristic compared to what could be done in 1890. Count Zeppelin himself couldn't be said to have achieved a really practical rigid until around the time the Wright brothers flew, though his first attempts which did fly (not very well though) were years earlier. Other designs flew earlier but it wasn't until Alberto Santos-Dumont started making his blimps (again in the first decade of the 20th century, when suitably light and reliable gasoline engines became available) in Paris that I'd say really workable LTA that wasn't basically a free balloon with some minor maneuverability had arrived.
The problem of structure, including both the problem of holding the gas bag stiff against aerodynamic forces tending to bend or otherwise distort it and the problem of suspending the non-balloon structure from a balloon was a tough one. If you look at the sorts of airships people were typically flying in the first decade of the 20th century, typically what we have is a sausage-shaped gasbag (that might possibly be stiffened somewhat by pressurizing it with a ballonet) with a net over it and a bunch of wires hanging down to suspend a rigid girder hung below, on which the pilot, fuel, engine, props and control surfaces would ride. Such a structure obviously can't achieve much airspeed even with a good engine. The Italian approach was to develop that design by integrating the girder into the aerodynamic (more or less--again people understood aerodynamics poorly and anyway it's hard enough to build a simple structure, making it comply with aerodynamics as much as possible makes the job harder) gasbag to develop the typical "semirigid" design philosophy. Parseval in Germany probably had the most advanced nonrigid design ideas, involving ingenious suspension from a pressurized gasbag; other notions included the Astra-Torres design that partitioned the gasbag into three lobes (a cross section would look like a clover) thus putting the suspension lines inside them. It wasn't until after WWI that some expatriate designers formerly working for Zeppelin in Germany (and at this point working for Goodyear in the USA, wearing more than one hat--they were also founding employees of the Goodyear-Zeppelin company, a subsidary of Goodyear that had licensed rights to share some tech with Luftschifftbau Zeppelin in Germany, but when they worked on blimps they were operating as employees of another Goodyear division) developed the modern design of the typical blimp, with a unitary well-streamlined gas bag hull with internal catenary suspension curtains bearing the gondola snug against the hull.
I'm not sure how many of these designs might have had some practical version using 1880s materials, but even if that could be done, adequate strength and other essential properties (resistance to gas permeability for instance) would probably require more significantly more weight for a given volume, cutting into the margin available for payload and fuel. Engines in particular would be either weaker or heavier, probably both.
Heck, many of the would-be dirigible makers of the late 19th century didn't even use pure hydrogen for their lift; there's "town gas" which was commonly available in the 19th century for gas lighting, made by blasting coal with steam--this produces a mix of hydrogen and carbon monoxide, since the latter weighs about the same as air and the gases were in 1:1 proportion by volume, this stuff had half the lift of hydrogen. (And was just as flammable and also poisonous!) It was very easy to get though, trying to refine the carbon monoxide out of it for pure hydrogen would be tough.
I think that just maybe, generals looking at the prospect of a real war coming soon might decide the available dirigibles were good enough to have some use and therefore purchase some and set about fostering their improvement, in house or by their contractors. If one nation did this, another might feel they had to try and keep up, so very possibly we do have small armadas of small, slow dirigibles, basically motorized kite balloons.
The kite type of observation balloon by the way--we might more readily call a picture to mind if we think of WWII barrage balloons, basically a blimp-shaped balloon--seems itself to have been developed remarkably late; I just glanced at the Wikipedia article on
observation balloons and while of course military use of the basic spherical type balloon goes back to the French Revolution, there's no discussion of the more steerable, more airworthy kite type until the context is again WWI. I'd have thought they'd have been empirically evolved during the 19th century but it seems
Albert Caquot came up with the first decent design in 1914!
On the other hand the British were using mobile observation balloons in the 1880s in Africa OTL, so in this timeline I might think maybe some conflict or other somewhere provokes someone to improve the station-keeping abilities of a tethered observation balloon some decades earlier by shaping the hull, adding suitable stabilizing surfaces of some kind, and other innovations.
So the airships of the mid-1890s might be a bit better than OTL, if they are using gasbags derived from more advanced kite observation balloons. But not a whole lot.
The war might foster hothouse advances in dirigible design, but I find it hard to believe they could even come close to the OTL state of the art of 1910, which was not all that impressive.
Unless of course again you compare to having no airships at all, or to the sorts they had before the war.
If these advances include developing either better structural materials or better engines, then they will make development of an airplane of some kind easier, but if the war drags out just a few years we'd be within half a decade of the Wright brothers' first flights anyway.
What the war might do to change aviation history then, is possibly establish the airship in a very primitive form as a familiar and somewhat ubiquitous technology that has some practical use after the war, then postwar the ambition to establish serious airlines might take hold and we might get an early airship era using materials and engines comparable to what the Zeppelin works had available in the pre-war 1910s, but with somewhat superior aerodynamic design and structural cleverness developed empirically.
Count Ferdinand Zeppelin himself might or might not be butterflied away at birth, but his career seems unlikely to lead to developing his notions of a rigid-frame airship. OTL, he served in the army of the Kingdom of Württemberg and visited the USA during the Civil War to observe; it was there he had his first experiences with ballooning. His ideas for airship designs (many of which were quite impractical--his firm eventually did a lot better when he stepped aside and let real engineers design the airships
) were clearly something he thought about a lot, but he didn't do much OTL until he resigned from the Army in 1891--and he did that because he protested the degree to which the Württemberg army was becoming dominated by Prussians.
Here, even if we assume the Count (born 1838, it would take pretty strong butterflies of the type I think we can take advantage of if we want but also defy if we want that) is essentially the same person, the history of Germany is quite different. I forget if the Kingdom of Württemberg would be distracted by serious problems in the early 1860s that would keep the Count at home rather than studying the Civil War. Also that war is shorter and so he has less time to be influenced by it. Assuming nevertheless that he does go to America and among other things becomes a hydrogen-head (or he gets the ballooning bug some other way in Europe) and then returns to Württemberg--now, at least until the war, Württemberg is an independent kingdom, not part of the German Empire. It seems much less likely he'd have to resign from the Army, and so while perhaps he could have influence in government circles to promote a government airship project, on the whole it seems less likely his name or his notions of design would have the meaning they do OTL.
OTL, Zeppelin had a German competitor, Dr. Johann Schütte, who ran a rival firm that also made rigid airships. Indeed in some respects Schütte's early rigids were much more advanced than Zeppelin's early attempts and during the war the Zeppelin company took advantage of government-mandated patent pooling to appropriate some Schütte innovations. But Dr. Schütte was inspired to attempt this by Zeppelin's early attempts which failed; if there were no Zeppelin firm, probably no Schütte-Lanz either. Anyway all this was in the early 20th century.
However, Schütte-Lanz firm was based in Mannheim--which is also in Württemberg! Actually looking at the articles on that kingdom apparently it was quite the intellectual hothouse; Einstein (much more likely to be butterflied beyond all recognition here of course) was born there, a great many famous German universities are there.
So, while Dr Schütte himself might have been too young to play his OTL role (or butterflied away) perhaps the Count does persuade the royal government to undertake some serious airship development in the 1870s and '80s, and this draws in some serious talent resulting in the best design possible given basically 1880s tech. We might even get Schütte's famous (or infamous, if that is how it strikes you) wooden frame design. OTL by the time his ships were flying, advanced forms of aluminum (Duralumin) were being developed, but until some such metal becomes available, plywood frames would indeed be superior to available metal alternatives--from the point of view of strength/weight ratios, it has serious drawbacks such as tending to warp and come apart due to absorbing moisture that have to be addressed. Someone else would hit on it I suppose.
On the other hand, while Württemberg obviously has a remarkable development of intellectual culture OTL, would that be true here? It seems to have deep roots, but what effect would staying out of the (North) German Confederation and perforce being allied with France or Austria have? To what degree are the South German kingdoms in a de facto Confederation of their own--or indeed are in the North German dominated Zollverien? (We've discussed this part). If Württemberg were not part of the German Empire in the 1870s and '80s, would her industries and thus support of her scientific/engineering institutes be comparable to OTL? Military competition and uncertainty might make the government more inclined to fund technical ventures--but would they be doing so on an impovershed base?
Anyway if little Württemberg is making strides in impressive new airship designs (and can actually make them work impressively with 1880s engines) I suppose other greater powers will make some efforts too, and achievements we associate with Zeppelin OTL might not even be German but French, British, possibly American, or Italian. (Or conceivably Russian or Turkish).
