So, a game of World War I flying aces, with the key ingredient that's been lacking from other aerial combat games: intelligent apes... now, I cannot say that I've ever felt the lack of apes, intelligent or otherwise, in any aerial combat game I've played but... now I've read this, there's a certained warped corner of my mind that sees that they could be an asset!
The premise is simple. Back in the 17th and 18th century, human explorers from Europe found civilisations in distant jungles built not by primitive men but by apes. Urang utans swarming over the Indies. Chimpanzees in West Africa. The apes took advantage of the encounters every much as humans did, and by the beginning of the 20th century, they lived in the west enjoying all the benefits of civilisation in harmony with their hairless cousins, human beings. Five ape species have stepped up to take their place in society: Orangutans, Gorillas, Bili Apes, Chimpanzees and Bonobos.
After this swift yet comprehensive history we move on to Character Creation, which uses the QAGS ruleset (which you will need to make the most of this game). Characters may be humans or one of the ape species and details of the 'ape modifier' that you apply to any ape character are spelled out here. Given the original premise of the game, characters are intended to be pilots... but there is plenty of material if you intend a more general early 20th-century alternate history game where aerial action is not quite so important.
The next section discusses the Great War, weaving actual and alternate history into a seamless whole to set the scene for the game. Positing a date of 1916 when combat had settled into trench warfare with biplanes buzzing about overhead, the next section looks at the Flying Squadrons and how aerial combat was conducted. Aircraft, the nascent art of war in the air, even uniforms and squadron life are covered. The section ends with game details for several different aircraft.
And then... Flying Monkeys. It doesn't matter if you are human or ape, you need to be aware of certain details - and the rules that will model them. The effects of altitude, even frostbite, must be survived. A system for aerial combat itself is then presented, which a few die rolls and prangs later can be reported to be mostly workable, although a knack for abstracting and presenting the combat in narrative form improves things greatly. It's not about rolling dice, it's about adventure and derring-do, after all!
Finally some notes on the sort of adventure that ought to work well are followed by a fully-developed one, Masque of the Black Death. There's plenty there to get a good flavour of the game. A whole raft of appendices deal with the timeline of the alternate history, pre-1916 aircraft, the major nations, other theatres of war, speaking ape (common ape slang), a Great War glossary and (of course) some dumb tables to exercise your die-rolling skills upon. There's even a page of Inspirations, a GM cheat sheet and a character sheet - everything you need, really.
All jolly good fun, what? Gentlemen, gentleapes, start your engines!