3.4.7 Tiedown devices. Trailers shall be provided with tiedown devices, in accordance with
applicable drawings and of sufficient number and structural strength to be adequate for transport
by rail, sea, and air (see 4.8.9).
3.4.8 Air brake system. Trailer braking system includes air actuated service brakes equipped
with fail safe units to provide parking and emergency braking. The air brake system shall be
capable of operation throughout all ranges of trailer operating conditions. The brake adjustment
system shall function properly and maintain adjustment within required settings during all trailer
operating conditions (see 4.8.10).
18.104.22.168 Air lines and fittings. Air lines and fittings shall be internally clean prior to and after
making connections and shall be free from leaks. All lines and fittings shall be secured to prevent
rubbing on adjacent lines or trailer appendages. Air system leakage shall not allow a pressure
drop of more than 34 pound force per square inch (psi) in a 1-hour period, with 100 + 10 psi
(shop air) initially in air supply tanks, and ambient temperature of 700 + 100F; or 6 psi drop at
120 + 10 psi for 2 minutes at 700 + 100F (see 22.214.171.124).
126.96.36.199 Brake actuator seals. The brake actuator shall be completely sealed to preclude
leakage of lubricants and the entrance of water, sand, or other foreign matter into the actuator
during normal operation and fording as specified in 3.5.8 (see 188.8.131.52).
3.5 Performance. The trailer shall meet performance requirements of this specification when
equipped as specified herein, serviced as specified in applicable lubrication drawing, loaded with
M976 or M1033 payload (see 3.5.2 and 3.5.3) and coupled to the towing vehicle (see 4.8.11
3.5.1 Environmental conditions. The trailer, when properly serviced and coupled to a
suitable towing vehicle, shall operate and transport equipment in ambient air temperatures from
minus 50 degrees fahrenheit (0F) to 1200F. When in storage, the trailer shall withstand
temperatures from minus 50 0F to 160 0F without deterioration that causes failure of any
component (see 184.108.40.206).
3.5.2 Simulated M976 payload. Performance and functional characteristics specified herein,
reliability, and maintainability requirements shall be met with a payload of four PATRIOT missile
containers loaded to a gross weight of 3,740 lbs each, with a center of gravity as indicated by the
containers and mounted with the M976 mounting devices (see 4.8.11).
3.5.3 Simulated M1033 payload. Performance and functional characteristics specified herein,
reliability, and maintainability requirements shall be met with a payload of 30,000 lbs securely
fastened to the trailer in the following position. The center of gravity of the simulated load shall
be located centrally across the vehicle, 48 3/8 inches above the loading deck and 239 inches to the
rear of the kingpin centerline (see 4.8.11).