Escort see me without pinging

[BigWalleye]

From The Fleet Type Submarine NAVPERS 16160, June 1946, Page 177
(Available on-line at http://www.maritime.org/doc/fleetsub/)

The state of exact neutral buoyancy is probably never attained, but the approximation is near enough to allow depth control to be exercised easily by the diving officer.

In all normal submerged operations, the submarine is underway at relatively slow speeds. This horizontal motion through the water enables the surfaces of the diving planes to correct the effect of any slight positive or negative buoyancy and also to increase or decrease the submerged depth at the order from the conning officer.

From The Submarine Commander's Handbook (U.Kdt.Hdb.), OKM 1643, dated 1943:

247.) As a matter of principle, the submarine which is the object of enemy underwater pursuit should behave in such a way that it remains active, and should try to make good its escape by availing itself of every possibility, instead of simply waiting, and lying passively at the bottom. Activity on the part of the submarine always offers the best chances of shaking off the enemy.

From their training manuals, it seems that neither the USN nor the KM was aware of the possibility of a submarine remaining motionless at a constant depth. These manuals describe practical operations, not theoretical possibilities. (The theoretical possibility of establishing neutral bouyancy, and thus remaining stationary is indiputable. The question is whether this was done or could be done operationally, more especially in combat.)