I find it disturbing that Muv-Luv managed to get a thread here, there's so many better anime in the past two seasons that deserves attention over this one.
Basically the setting is on an Alternative Earth overrun by Aliens called BETA. Total Eclipse is actually a sidestory to the Main storyline in the VN's The First incursion with the BETA began on the moon and eventually ended in failure due to their overwhelming numbers They first began devastating Asia as soon as they evolved a countermeasure for Planes and Nukes and basically start owning humanity And basically reduced the Human population to 1 Billion in time The series starts with the BETA's invasion of Japan but then has a timeskip for three years where it goes to the main protagonist Yuuya Bridges a part Japanese American TSF pilot with issues with his heritage It's like Starshiptroopers, Top Gun and Gundam I will say it does have moments of annoying fanservice but the story is decent enough to where it can be ignored. It especially picks up during the Russia arc