[quote=@Jotunn Draugr] MS Paint... Or tell me where you want to be, and I'll add you to the map. This really conflicts with the entire setting. I'm gonna say "no". This is Alt-History, not Sci-Fi. I think jet engines would directly conflict with the tech levels of everyone else. Steam power, man! Steam power! Think late-Victorian, with some out-of-place tech directly resulting from coal-burning. [/quote]Steampunk is sci-fi in the past and many classics which made steampunk were actually sci-fi during their age and also featured aliens at times. While aliens are a bit weird to even exist, I added it as a complication rather than an actual advantage. I could have Africans with Tripods and it wouldn't change much. But the mechanism how Martians interact is too much fun to miss. As for jet engines, no. Actually given the mechanics of steam, turbine engines make far more sense to be developed sooner. Also jets were a thing by mid-WW1. It just took a while to develop them. But again we have mechs so arguing against jets seems arbitrary. Blue coal explicitly can replace gasoline engines here so building turbines either for jet propulsion or driving propellers like turboshafts is hardly out of reach.