When the United States entered World War II, our
Navy was faced for the first time with the problem of
landing and supplying large forces in areas where
traditional harbor facilities were controlled by the
enemy. Navy Lightered (N.L.) pontoons were
developed in 1942 to meet this difficult situation. They
were designed for erection by naval personnel and
shipment aboard Navy vessels. These pontoons
pro-veal to be an invaluable asset and were used
extensively in operations during World War II, the
Korean conflict, and again in Vietnam.
P-series pontoons were used throughout the
Republic of Vietnam in combat conditions. Although
originally designed to meet the requirements of the
Advanced Base Functional Component (ABFC)
System, they have been used successfully in many
other fields due to their inherent versatility and ease
of erection. Large structures are easily and quickly
disassembled then made into smaller structures, and
then the smaller structures can be quickly and easily
reassembled into larger structures. The light draft,
structural strength, mobility, and adaptability of
pontoon structures made them extremely useful for
shallow water passage and tactical deployment in the
Mekong Delta. They allowed movement of heavy
weapons and shifting of firepower throughout
otherwise remote areas. Many structures not
discussed in this manual, such as armored barges,
helicopter pads, mortar barges, and barracks barges,
were constructed in the field for use in special
situations throughout the waterways of South
TYPES OF P-SERIES PONTOONS
Five basic types of P-series pontoons are in use
today, designated Pl, P2, P3, P4, and P5. These
pontoons are specially designed, internally reinforced,
welded steel cubes. They are tested to withstand an
internal pressure of 20 pounds per square inch (psi).
All pontoons have plain deck plates covered with a
nonskid coating, and all are, fitted with a 2" plugged
hole for air, drain, or siphon connections at the top and
bottom of one of the end plates.
The P1 pontoon is cubicle in shape. (See fig.
10-1.) The deck of the P1 is 5'3/8" x 7', and the sides
are 5'3/8" high. The side, end, deck, and bottom
plating is 3/16" thick. The P1 is the most common and
widely used pontoon in the P-series. Its usage is
required in every structure of the pontoon system.
The P2 pontoon has the same depth (5'3/8") as the
PI, but it has a 7 square deck and a straight-line
sloping bow. (See fig. 10-2.) The side, end, and deck
plates are 3/16" thick. The sloping bow plate is 3/8"
thick. P2 pontoons are used on the bow and stern of
various pontoon structures.
Figure 10-1.P1 pontoon.
Figure 10-2.P2 straight-line sloping bow pontoon.