You have been initiated into the wonderful world of the pitchpole. this is a problem that as far as I know has been pretty exclusive to the hobie 16 because of the tapered nature of the bows of each hull. this is a problem that will forever plague you to some degree or another as long as you have the boat. the quickest and most surefire way to avoid this is to buy some anti pitchpole hydrofoils and install them on the bow of each hull. With these installed those bows will never again bury themselves in the water. However, a true skilled cat sailor would never be caught with those on his boat......
The aquatic car wreck known as the pitchpole takes place for one very simple reason. You have a Jib. there are several remedies that can alleviate your boats tendency to do this on whatever tack you are taking. Some say the best remedy is to Rake your mast back even further and this will prevent it from happening I have tried this and in moderate winds it helps but if you love high winds then it doesn't do much of anything. my personal remedy has been the jib travelers. the problem is that in high winds there is so much force being exerted on the jib that it is pushing the nose of the boat right down into the water.. so to fix this you need to spill some of the air off the jib at a greater rate without losing any of the speed that the jib brings to the boat. Hence the travelers. the best way to get the feel for it is to loosen the jib at first and sacrifice the speed as you learn the best way to position the travelers. the further out you go with them the more air spills off the jib and lifts the bow, but you can also lose speed, so you need your crew to be experimenting with that sweet spot where you are spilling enough air to keep the bow from diving but are right on the razors edge where you can keep the best speed both tacking up into the wind and downwind.
The travelers have been the best solution I have come up with for avoiding that problem but even they are not fool proof. just the other day I pitchpoled right out into the jib and watched the boat roll over on its side. But to me that is just fun you are not really having a good time sailing if you are not constantly flirting with disaster. So play with different remedies and see what works best for you and your crew, the thing about Sailing a 16 is that it is a constant evolution of fine tuning to get the best possible experience.. Good luck and I hope this helps.