Its an AIM-9M with more pull and more range.
In honesty its a bit of a consolation for the F-2s lack of HMD, and lack of ARH missiles compared to contemporaries.
The main thing that it can do that the 9M cannot is that you need to watch for the 6km top down shots. If you are on the deck always watch out for an F-2 up in the sky because those AAM3s can absolutely reach you.
Ive gotten many kills on enemies who never expect an AAM3 from space.