SPECIAL ARMAMENT STOWAGE SPACE ELEVATORS (SASS) .- The SASS elevators provide service from the special armament stowage spaces to the hangar deck. These elevators are essentially the same as the 5,550-pound, lower-stage elevators with two major differences. The operator of the SASS elevator actually rides the platform from one level to another (personnel are strictly prohibited from riding the platform on all other weapons elevators). The SASS elevator also differs from the 5,500-pound elevator in that the trunk is provided with a hangar-deck hatch. When closed, the hatch becomes part of the hangar deck. The hatch is opened mechanically through the elevator control system. The hatch is lifted up into a horizontal position and moved rearward by rollers that ride on rails in the deck

INPROVED WEAPONS HANDLING SYSTEM (IWHS) LOWER-STAGE WEAPONS ELEVATORS.- The IWHS lower-stage weapons elevator (fig. 11-16) services magazines and ammunition handling areas from the 7th deck level up to and including the main deck (hangar deck). The IWHS is a highly sophisticated system controlled by a PDP-14 programmable controller that continually tracks the location of the platform to within one-twelfth

Figure 11-16.-Typical IWHS lower-stage weapons elevator.

of an inch. Because of the complexity of the IWHS, elevator operators and maintenance personnel are extensively trained in hydraulics, electricity, and electronics.

The platform is lifted by four cables attached at the corners. The platform machinery is located at the 3rd deck level. The hatches are opened hydraulically. They are designed to automatically undog-open-latch and unlatch-close-dog. The elevator doors are also operated hydraulically.

The IWHS incorporates the following safety features:

An overspeed governor slack-cable device

An overspeed governor device

A hydraulic interlock to prevent two hatches from being opened at the same time

A hydraulic interlock to prevent hatches from closing when dogs are in the dogged position

An electrical interlock to prevent opening a magazine door unless the platform is at that level

An electrical interlock to prevent opening more than one magazine door at a time

A pressure switch to prevent operation of the elevator when the hydraulic pressure is below 1,200 psi

An electrical interlock to prevent platform high-speed travel beyond the sequence-level slowdown switch

An electrical interlock to prevent platform travel beyond the sequence level until the main deck hatch is opened and latched

An electrical interlock to prevent movement of the platform until the lockbars are fully retracted

In addition to the operator controllers located at each access door and the 2d deck main controller, a portable main controller may be used at the main deck level. Normally, there is one IWHS installed forward to service the forward-magazine group and one installed aft to service the aft-magazine group. These elevators support the Improved Rearming Rate Program (IRRP).

UPPER-STAGE HYDRAULIC ELEVATORS.- Upper-stage hydraulic elevators (fig. 11-17) are used to transport weapons between the second deck and the main deck only. The major components of each elevator are an enclosed, watertight, vertical trunk, an elevator platform assembly, a hydraulic power plant system, and a semiautomatic elevator control system.

If an excessive elevator downspeed occurs, an overspeed valve closes and stops the elevator. The overspeed valve is mounted on the lower end of the lifting ram hydraulic cylinder assembly.