Condolences!
The Model 12 aficionados on this Forum will be of great assistance. I am not 100% sure if the Model 12 was ever actually known as an "airweight". Well, I checked, yep, I guess it was. I have a 4" in my collection; I don't think it is marked "Airweight"; maybe that's why I was incorrect.
Anyway, what I really want to be sure to tell you is to verify if this model has the steel or aluminum cylinder. The folks who know will be able to tell you from the serial number or wait until one of us looks it up. You want to be careful about what/which ammunition you shoot in it, especially if it's an older one with an aluminum cylinder. A magnet can answer that question.
Hornady now makes lighter loaded .38 Special ammunition; I obtained some solely for use in my Model 12, but I don't shoot it much, anyway. Enjoy yours!
***GRJ***