"The depth bombs dropped by the PBY had damaged the U-boat's diving planes
, surface lights, and had forced the vessel to reduce its speed to 11 knots."
The second movement, 'Blow, thou winter wind' uses slurs to sound like diving planes
and the final movement, 'Heigh ho, unto the holly' is a hymn for all who faced death in World War I."
Improvements such as double hulls, diving planes
to power descents, gyroscopes, periscopes, deck guns, snorkels, increased torpedo capacity, etc.
They also survived skin-ripping coral, diving planes
and, worst of all, bars that didn't exist.
6 feet long and 10 feet wide were mounted in line with the forward conning tower and operated by a lever inside the sub.
To escape gravity, scientists have also tried creating temporarily weightless environments, for example in the bellies of diving planes
, but then they have only seconds in which to conduct their experiments.