inner diameter of the nozzle orifice should be
designed such that they do not impede the movement of the
inch (12.7 millimeters). The nozzle must be able to
cannons or the wash water flow stream. If the user requires,
deliver pressures and flow rates within the recom-
hose connections may be included in the island design for clean
mended ranges with minimum losses.
up purposes. Figures-S shows a cross section of the wash
Motion restriction. Adjustable restraining bridles
h. Flexors. Flexors are grout or concrete filled, steel piping
(fig 5-3) should be placed at each water cannon
position to limit both horizontal and vertical move-
installed on the bottom of the bath lane to improve removal of
ment. Without the restraints, personnel could
encrusted dirt from under the skirts, around drive wheels, and
accidentally spray each other during cleaning
other areas of the vehicles that cannot be cleaned by the water
operations which could result in injury.
cannon flowstream. By driving the vehicles back and forth over
the flexors, much of the dirt can be loosened and removed. The
g. Cannon islands. Water cannons are mounted in concrete
turbulence created from this action also removes dirt from hard-
islands constructed at each corner of the bath lane. Figure 5-3
to-reach areas in the undercarriage, and behind side skirts. The
shows two example configurations. The concrete islands should
spacing and height of the flexors cause the tracks and wheels to
be located on the entrance and exit ramps of the bath. Two
move in an up-and-down motion. This movement loosens dirt
cannons should be placed in each inner cannon island (fig 5-3).
from the tracks and from under wheel wells and skirts. The
The outer islands should have one cannon per island (fig 5-4).
space between the flexors also serves as a collection channel
The islands must have drainage so that troops will not be
sloped toward bath lateral trench drain.
standing in water. All corner sections within the bath should be
filleted to avoid the buildup of debris. Cannon island shall be