Learning Objective: Identify functions and components for rain repellent utility systems.

The rain repellent system discharges fluid onto the pilot's and copilot's windshields from a

Figure 1-21.- Windshield washer system.

nozzle located at the base of each windshield. A timer circuit regulates the sequence of flow. The rain repellent fluid is distributed over the wind-shield surface by the windshield wipers and free stream air. A transparent film is formed that greatly reduces water adhesion. The film causes the water to form into streams, thereby preventing production of a vision-distorting film.

The rain repellent system is actuated by setting the wiper switch on the windshield panel to HIGH (fig. 1-22). This is done to minimize the possibility of rain repellent fluid discharge on a near-dry windshield, which could impair vis-ibility.

When the rain repel switch is depressed, both valve nozzle assemblies open, and the timer is energized. Rain repellent fluid flows from the nitrogen-pressurized container, through the manifold and plumbing, and out through the two valve/ nozzle assembly solenoid shut-off valves onto the windshields. The valve nozzle assemblies are energized by 28-Vdc power from the left primary dc bus. The rain repel switch must be released and again depressed for additional applications of rain repellent fluid. Approximately 60 applications are available from a full container. The rain repellant system consists of a recharge-able container and manifold, valve/ nozzle assembly, and plumbing.

RECHARGEABLE CONTAINER AND MANIFOLD

Rain repellent fluid is stored in a nitrogen-pressurized rechargeable container located be-hind the pilot's seat. Container capacity is approximately 0.9 pint. Container pressure varies from 75 psi (full) to approximately 30 psi (nearly empty). A manifold is mounted on the container. The manifold incorporates a pressure gage that indicates pressure in the container.

VALVE/ NOZZLE ASSEMBLY

Two valve/ nozzle assembly solenoid shutoff valves, one for each windshield, are located at the base of the windshields. An adjustable timer circuit governs the amount of fluid released onto the windshields.

PLUMBING

Plumbing consists of tube assemblies that connect the container to the valve/ nozzle assemblies. A drain cap is located at the low point of the plumbing.