Potvis triple hull type submarine The first design of a
triple hull submarine dates from the year
1942, the all time low of the Second World War. The
shipbuilding Engineer of that time, M.F.Gunning, who
was working at the Dutch Navy department in London, had the idea in the same
period as the successful campaign of the Africa corps under the German General
Rommel, which was then in the vicinity of Alexandria in Egypt. Malta
could only be held in Allied hands at the cost of terrible loss in those days.
It took only a simple calculation, that a submarine with a cargo
capacity of 500-1000 ton (cubic meter) could deliver as much cargo in about 3
months as some ships of the famous "Maltese convoys" that reached
their destiny. By means of constructing a cargo-submarine
with a hull consisting of three cylinders, a boat would be made with enough
cargo capacity to meet the needs of the demand. The machines and batteries would
be placed in the two relative smaller cilinders below, in doing so creating a
lot of space for the cargo compartment. In fact, a more
detailed predesign plan was brought to the attention of the British authorities,
and among them the Chief of the British Submarine Service , Sir Max Horton.
This produced little result, because the British were convinced
that Rommel soon would be about to leave Africa. Because
of this, a cargo-submarine would become obsolete. Another
drawback was the construction time of at least one year, and because of that the
British rejected the plan. Sir Max Horton saw some
opportunities however and so Ir Gunning got the request to produce a scketch
of an operational submarine of this type. Within a few
weeks, the design was on paper, but in the mean time Sir Max Horton had been
promoted to Chief Western Approaches, and
for that reasonthe project receded into the background.
After the war, when the Dutch Submarine Service had to think
of redevelopment just like the rest of the fleet, a lot of submarine projects
were worded out on shipbuilding department of the Dutch Ministry of Navy,
according to the same staff specifications, tonnage's and power. In December
1948 the
final decision was in favour of the design of engineer Gunning. The
triple hull submarine had the preference, the main
reasons were:
-A good balance of weight
-A better space partition
-A better ventilation flow
-Two separated propulsion devices, which would be easy to attain in case of a
repair action.
All these points were in favour of the triple hull types of
about 1150 -ton (cubic meter).
Click to enlarge
Displacement
.
1530 ton emerged 1826
ton submerged
Dimensions
length width
draught
79,50 meter 7,80
meter 4,95 meter
Propulsion
diesel electro
2 MAN 4-takt engines,12
cylinders after refit: 2x SEMT Pielstick PA4 2
Smit electromotors 2x168 cells of British making After
refit: 2 Holec electromotors 2x 168 Varta-cells from Germany
Power
diesels electro
2x 1250 apk, after refit 2x
1550 apk 2x 2200 apk
Speed
emerged submerged
14,5 knots 17
knots
Screws
.
2
Crew
.
67
Armament
.
4 bow tubes of 53,3 centimetre
4 stern tubes of 53,3 centimetre
was working at the Dutch Navy department in London, had the idea in the same
period as the successful campaign of the Africa corps under the German General
Rommel, which was then in the vicinity of Alexandria in Egypt. Malta
could only be held in Allied hands at the cost of terrible loss in those days.
It took only a simple calculation, that a submarine with a cargo
capacity of 500-1000 ton (cubic meter) could deliver as much cargo in about 3
months as some ships of the famous "Maltese convoys" that reached
their destiny. By means of constructing a cargo-submarine
with a hull consisting of three cylinders, a boat would be made with enough
cargo capacity to meet the needs of the demand. The machines and batteries would
be placed in the two relative smaller cilinders below, in doing so creating a
lot of space for the cargo compartment. In fact, a more
detailed predesign plan was brought to the attention of the British authorities,
and among them the Chief of the British Submarine Service , Sir Max Horton.
This produced little result, because the British were convinced
that Rommel soon would be about to leave Africa. Because
of this, a cargo-submarine would become obsolete. Another
drawback was the construction time of at least one year, and because of that the
British rejected the plan. Sir Max Horton saw some
opportunities however and so Ir Gunning got the request to produce a scketch
of an operational submarine of this type. Within a few
weeks, the design was on paper, but in the mean time Sir Max Horton had been
promoted to Chief Western Approaches, and
for that reasonthe project receded into the background.
