4.6 Methods of inspection.
4.6.1 Automatic inflation operation. The automatic inflation operation
of the ring buoy shall be tested by throwing the ring buoy encased in its
shell into a body of water. The ring buoy shall fully inflate within 10 seconds
after hitting the water. Failure of the plastic shell to separate, evidence
of leaks, partial inflation or no inflation after 10 seconds shall constitute
cylinders. The C02 filled cylinders shall con-
form to the following quality conformance inspection tests of MIL-C-601:
4.6.3 Leakage. The ring buoy shall be fully inflated with air through the
inflation system to a pressure of 2 pounds per square inch (lb/in²) and allowed
to stand for a minimum of 4 hours. At the end of this time the pressure shall
be measured and corrected for any change in temperature or barometric pressure.
The pressure drop shall be not greater than 0.25 lb/in2. Seams and sealed areas
shall remain intact and shall show no signs of separation.
4.6.4 Drop test. The encapsulated ring buoy shall be dropped three times
from a height of 6 feet onto a fixed steel plate. Failure of the ring buoy to
function as specified in 4.6.1 after this test shall constitute noncompliance
4.6.5 Vibration test. The encapsulated ring buoy shall be subjected to
a type 1 vibration test of MIL-STD-167-l. Upon successful completion of this
test, the ring buoy shall be subjected to the auto-inflation test of 4.6.1.
4.6.6 Buoyancy. Immediately upon completion of the auto-inflation test
(see 4.6.1), the ring buoy shall be tested as follows to determine the buoyancy.
In this test, the inflated ring buoy shall be placed in a cage of adequate size
and of sufficient weight to submerge the ring buoy. This assembly shall be
suspended from a direct reading scale, in fresh water, at room temperature, with
the top of the cage 2 inches beneath the surface of the water. The scale reading
shall be taken as soon as practicable and the buoyancy calculated as the apparent
weight of the cage and inflated ring buoy subtracted from the previously deter-
mined underwater weight of the assembly without the inflated ring buoy. This
calculated buoyancy shall be a minimum of 20 pounds.
4.6.7 Temperature. The ring buoy shall be placed in a circulating air
oven maintained at a temperature of 65 + 3°C for a minimum of 20 hours and then
placed in a cold chamber at a temperature of minus 30 + 3°C for a minimum of
20 hours. Upon completion of this test the ring buoy shall pass the test speci-
fied in 4.6.1.
4.6.8 Salt spray. The encapsulated device in its plastic bag shall be
subjected to a 100-hour salt spray test in accordance with ASTM B 117. Immedi-
ately following the salt spray test, the device shall be subjected to the tests
specified in 4.6.1 and 4.6.3.