designed to act as a single spring by means of rods (3) that pass through each set of springs and end in eyed terminals (6). The inboard ends of the rods are bolted to clevises (2), which are welded to an equalizing plate (l). The plate has a threaded adjustable rod that is secured to the ship’s structure to hold the inboard ends of the spring unit. The outboard ends of the rods are bolted to a similar plate, which has a welded clevis outboard, through which is bolted the eyed terminal of the counterbalancing spring cable. The cable (7) runs through two sheaves and is then bolted through its terminal to the actuator arm of the barricade stanchion, below the point of attachment for the cylinder. When the stanchion is lowered by the cylinder, the sets of springs are uniformly compressed and resist the force of the descent, and cushions its fall against the deck. Raising the stanchion slackens the spring cable and decompresses the spring, but this release of compression has no appreciable effect on raising the stanchion. STANCHION LATCH Stanchion latches are used to secure the stanchions to the deck in their DOWN position. Stanchion latches (fig. 3-39) are spring-loaded latches bolted to the subdeck and provided with a slotted frame, designed to allow the latch (5) to bc retracted against the force of a spring (2), and turned to lock the latch open. When the stanchion 1. End plate 4. Body 2. Spring 5. Latch 3. Pin Figure 3-39.—Stanchion latch assembly. is lowered, the latch may be engaged in a hole provided in the stanchion, and a spring will hold the latch in. POWER PACKAGE The power package (fig. 3-40) provides and maintains the fluid pressure required by the hydraulic cylinders to raise and lower the barricade stanchions. It consists of a base weldment, gravity tank assembly (7), control panel assembly (8), accumulator (1), motor controller (9), pump (2), electric motor, electrical system, and piping system. The gravity tank assembly has a capacity of approximately 100 gallons and is the fluid reservoir in the power package assembly. Displaced fluid from the cylinder assemblies is returned to the gravity tank, and from there it is pumped back to the accumulator. The gravity tank is welded steel, closed at the top and bottom by flat plates. The top cover plate has an access hole, which is covered by a cap plate and gasket held in place by bolts. Tapped bosses welded to the cap plate are for breather vents. A Iiquid-level gauge is connected to the side of the gravity tank. An indicator plate is attached to the tank at the level gauge to show the proper fluid level. The control panel assembly (fig. 3-41) is attached to the gravity tank by four bolts. The panel consists of the panel frame (1), two piping support brackets (9), accumulator pressure gauge (6), pressure sensing switch (7), gauge valve (3), air-charging valve (5), vent valve (2), air supply valve (4), caution plate (8), and operating instruction plate (10). Necessary copper tubing and sil-braze fittings connect the panel to the accumulator assembly, to a ship’s exhaust line, and to the ship’s high-pressure air supply line. The accumulator pressure gauge (6) is used to indicate pressures ranging from 0 to 2,000 psi in the accumulator. The pressure-sensing switch (7) is a piston type, contained in a splashproof housing. It is connected to the pressure line from the accumulator with a threaded adapter and a coil of tubing between the adapter and tee in the pressure line. The function of the pressure-sensing switch is to maintain accumulator pressure between 1,250 psi and 1,500 psi. It does this by opening or closing to stop or start the pump motor. The pressure switch operates 3-42