https://www.mangago.zone/read-manga/rising_to_the_azure_sky/
It's finished, despite it being "on-going" on the website. It has very short chapters and it's more gag comedy than plot.
This next one has the same characters, but it's like a remake. It has longer chapters and it tells a coherent story, unlike the first version. It's finished as well.
https://www.mangago.zone/read-manga/rising_to_the_azure_sky_let_s_fly_together/
The manhuas are shounen ai though. You can totally read them both, but it depends what you're in the mood for: short and funny or longer and has plot.
And some manga, if you're interested:
https://www.mangago.zone/read-manga/soutai_flight_sign/
https://www.mangago.zone/read-manga/soujou_fly_again/ (spin-off to Flight Sign with another couple)
that's such a nice and exhaustive list thank you sm I really appreciate it!!
does anyone know of any yaois that have a plot around aviation, like one of the characters being a pilot, etc? rather niche but I'd be appreciative of any links!