Our A330-200's have jettison facility as do, I believe, our 767-300's. I only know about the 330's though so I'll stick to them. It is an option on the A330 - our sister company's A330-300's don't have it for example.
A320/321/330 can all be landed up to MTOW, provided the QRH Overweight Landing Checklist is followed. This has a few points to it, the main one being that the touchdown must be achieved at less than 360 fpm. There are also some configuration and climb gradient points to think about. An overweight landing check may or may not follow, dependant on circumstances of the actual landing.
The A330 QRH Overweight Landing Checklist states -
"Automatic landing has been certified up to Max Landing Weight, but has been demonstrated in flight up to Max Take Off Weight. In determining the best course of action, the crew may consider the option to perform an automatic landing, provided the runway is approved for automatic landing".
This opens up a very interesting debate - To jettison or not to jettison???? As far as I can see - no right or wrong answer to this - have discussed it at length with various trainers and they've all agreed that it's personal preference. However, the general consensus seems to be that if time is critical - don't dump, and if it isn't time critical or runway length/weather is a factor - do dump. I think I'll start a little thread of my own on this!!!
Hope this helps.
