When launching a fox-3 missile (RB 99) at long range when the missile is locked with its onboard radar, it starts spinning out as soon as the enemy visually de-renders and if not supported by TWS or STT.
It happens nearly every single time i look away and / or stop holding the TWS on the enemy and the missile doesn’t hit.
Here is a link to an in-game clip showcasing this, it can be seen on it that the missile spins out at the exact same time the enemy de-renders:
I think this bug has been around for at least 4 years. It’s very obvious in sim, where you can see enemy dots only within around 10 km UNLESS you are painting them with radar (any AA search mode and no lock or TWS reguired). If they have smoky engines you can see their smoke from 20 to 30 km away but not the actual dot.