Air Fleets of Mystara
by Giampaolo AgostaClassification
I'd divide flying fighting forces into a few categories, with different properties:
1) Skyships (Alphatian Man-of-War, Heldannic Sturmkondor, and the like): they are costly and require much magic, or, in case of Zeppelins, are dangerous, but can carry large number of troops (from a dozen or so to the 600 sailors and marines of the Alphatian Man-of-War, a true flying fortress) and heavy weapons. Useful for long range operations, these ships are able to work on their own for weeks.
2) Airplanes (Serraine biplanes and triplanes, Glantri's Dragonflies of Doom): these are skyships that need only one or two crew members to operate, and may carry no more than a dozen passengers. These skyships need to return to a land base or a carrier ship (currently, only Floating Ar and Serraine could be used as carriers).
3) Air cavalry/infantry (Pegataurs, R.A.F. hippogriff riders, Ee'aar): these are individual soldiers, either able to fly on their own or carried on a flying mount whose fighting ability is comparable to that of the rider. These troops need to land often, since the flyers tend to get tired.
4) Large flying creatures (Dragons and Rocs, with or without riders): these are large flying monsters, whose fighting ability usually exceeds that of the rider (unless the rider is of very high level); they can be used as fighter/bombers, and have longer range than air cavalry.
Outer World Air Powers
Heldannic Knights
According to Bruce Heard, the Heldannic Order can field 25 Waffenadler and 2 Sturmkondor warbirds. Each Waffenadler has a crew of 60, while a Sturmkondor carries 90 sailors and officers, for a total of circa 1700 members of the Luftflotte.
Both types of warbirds fit in the skyship category.
Empire of Thyatis
Thyatis relies on the Retebius Air Fleet and the Knights of the Air for aerial support. We have no hard numbers, but the Retebius Air Fleet assumed this name when the Retebius Aerial Corps grew to "several hundred warriors". So I'd put a lower bound at 500 units for the R.A.F., while the total air forces of Thyatis would have to be limited so that they cannot overpower the Alphatian aerial defences.
Anyway, since the Alphatians were never able to get great advantages from their own aerial forces (including the massive Men-of-War), I'd say that the combined might of the R.A.F. and the Knights of the Air would easily exceed 1000 units in modern times.
These are divided between air cavalry, mounted on hippogriffs, pegasi and griffons (85%), and large flying creatures, including sphinxes, rocs and dragons (15%).
Thyatis also has the magic necessary to produce "bumber-chutes", so it could potentially create a corps of paratroopers (carried by rocs and large dragons). However, this would be quite costly (more or less, a paratrooper equipment would be as costly as a knight).
Thyatis doesn't have skyship technology before WotI, but could acquire it from captured Alphatian dominions after the War.
City of Serraine
The Flying City of Serraine can rely (in addition to the city itself, which acts as an aircraft carrier) on 25 biplanes and triplanes, plus a number of Pegataur fighters (there are circa 120 Pegataurs on Serraine, we could say that 25 could be available as fighters).
There are also some Cloud Clippers, which could be used a troop transports.
Hagiarchy of Hule
While the Hulean army relies mostly on giants and juggernauts to achieve supremacy in land battles, the Legions of Doom include 10 Doomflyers each, with some 60 crewmembers each.
Doomflyers are useful as personnel carriers and mobile archery platforms, but carry no heavy weapons.
There is no estimate of the number of Legions of Doom (and therefore Doomflyers) available -- only one is used in the invasion of Sind, but more are likely to be available for use on the other borders (I'd say a total of five at least).
After the invasion of Sind, Hule may capture the Barge of Sayr Ulan.
Rajahstan of Sind
Sind has a single skyship, the Barge of Sayr Ulan, which is mostly an experimental craft. It can be used as an heavy bomber thanks to a lighting bolt weapon, though it is also armed with ballistae and catapults.
Alfheim
The elves of Alfheim have the ability to build Lightboats, through their clan relics. Moreover, powerful elven wizards also build Swan Ships.
Both types are small crafts, in the range of the airplane type.
They are usually unarmed.
Ostland
Ostland has a single skyship, owned by the pirate Oberack, an ally of the Ostman clan. Therefore, the skyship is not available to the army of Ostland.
Alphatia
While Alphatia is the known to be to foremost producer of skyship, we have no data on the number of skyships actually available to the Alphatian Imperial Navy -- the only Alphatian Navy mentioned in canon sources that I know of is the fleet of Floating Ar in the PWA, at the very limited size of 4 ships.
My estimate is that the Alphatians, pre-WotI may field some 20 Men-of-War, and a larger number of smaller skyships (much like the Princess Ark), for a total of some 15-20000 airmen, boltmen and marines.
Aeryl and Eshu
These nations of the Arm of the Immortal are inhabited by flying race.
Therefore, their entire armies count as air infantry.
The Ee'aar can field 2200 elves and 220 giant eagles, while the Enduk army is some 3000 soldiers strong.
Enduks are short range flyers, so they rely on Naaruks (a type of winged bull golem) for transportation. Each Enduk temple has at least one Naaruk, and each Naaruk can carry up to 10 Enduks, magically merged into its body.
Rockhome
The dwarves do not have a standing flying force, but are experimenting with the proto-zeppelin -- and since the gnomes of Oostdok are already able to build zeppelins, it is likely that the Skarrad dwarves could make working dirigibles if the need arose.
Glantri
The Principalities have a secret force of 12 Dragonflies of Doom, designed by Prince Volospin. These airplane golems can be used as fighter-bombers and for fast troops transportations, though they are limited to some 5 passengers.
Of course, many individual Glantrian mages are able to fly on personal devices or mounts.
Shadowelven Territories
According to the PWA, the Shadow Elves have a standing air cavalry of 500 units, mounted on skinwings.
This puts the Shadow Elves nearly on par with Thyatis, Glantri and the Heldannic Knights.
Hollow World Air Powers
Oostdok
The gnomes of Oostdok are able to build zeppelins, even though they are not much equipped for war.
Schattenalfheim
According to the PWA, the Schattenalfen have a flapsail cavalry with 1500 members.
Nithia
According to the PWA, 100 Hoverships compose the flying fleet of Nithia.
They have a limited flight height, so they may be at a disadvantage against more flexible flying troops.
Milenian Empire
The Milenian Empires keeps a standing elite air cavalry of 100 griffon riders.
Other Air Powers
Myoshima
The Empire of Myoshima can invade Mystara thanks to they flying tiger cavalry. They are likely to have the largest flying cavalry of all, on par with the entire Alphatian Skynavy.
The Dragons of Wyrmsteeth
While the Dragon nations aren't usually involved in Mystaran politics and warfare, a Myoshiman invasion could trigger a reaction from these creatures. The Wyrmsteeth is the largest draconic kingdom on Mystara, and can field up to a thousand of dragons in battle!