snap roll or trip of to one side.

I agree and the complete cockpit assembly with canopy, has to be able to resist the highest speed (water pressure) the boat will ever achieve AND with a safety factor, the cockpit loading spherical 360 x 360 degrees.

"from which a pilot controls the aircraft. Most modern cockpits are enclosed"

HUH ?? where was a open cockpit ever mentioned ????? This is 100% enclosed ,Rated and water tight!!!

Show Me!

Try post 234 and try to keep up !

A water tight cockpit will be very difficult to open if up side down due to the outside water pressure.

What is the best solution to this problem?

A secondary hatch in the tunnel will work for cats but not for v-hulls.
A valve to flood the cockpit in a controlled manner?
A tank of compressed air to increase pressure in the cockpit to match the water pressure?
Other solutions?

Thats an interesting solution and certainly viable when you think about it. Also with a sealed cockpit breathing air will be an issue.

Ok let's check the math: @ .44 PSI per foot sea water, Let's Say 8 feet down or 8 X .44 = 3.52 Psi, No big deal, Simply over pressure the cockpit or flip the boat back over. NO water in!!!! we are in a Drowning mess now.

Check Valve it!