Quote:
Originally Posted by Sailor Steve
Or in a faked picture.
"Hey, guys. Lean way over and I'll tilt the camera!"
On the other hand it's interesting that the bow planes are apparently at full down while the stern planes are almost flat.
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The pic may or may not be posed but thinking about it for a second and the zero angle on the aft planes makes perfect sense for the initial stage of the dive.
With both sets of planes at hard-dive the boat should tend to pitch down rotating around the centre of gravity (or perhaps the center of pressure which one would think would start forward and move aft to the CG as the boat achieves equilibrium in the dive.*) This might well cause the entire stern to come out of the sea and result in losing control of the rudders, aft planes and now free-spinning props. Good arguments to avoid big angles.
On the other hand with aft planes at or near zero, they should become the pivot point and so the props and control surfaces stay safely submerged.
If you can get hold of
Submarine Commander by Paul Schraatz, he goes into great detail about the problems and pitfalls associated with big-angle dives in diesel boats.
<*My background is in ballistics not hydrodynamics so this is a guess and anybody familier with pitch behaviour of vessels in water may freely debunk as necessary.>