Oral Flashcards
Why is it important that traces of welding Flux be removed after a piece of aluminum or magnesium is welded?
Welding Flux is corrosive and must be removed to keep the metal from corroding
What takes up the shock of the landing impact in the oleo shock strut
The metered transfer of oil from one compartment to another inside the shock
What takes up the taxi shocks in an oleo shock strut
Compressed air
How much oil should be put into an oleo shock strut
Deflate the strut completely, remove the filter plug and fill the strut with oil to the level of the fuller plug
What should be done to Hydraulic brakes when the pedal has a spongy feel
The spongy feel is cause by air in the brake , the brakes should be bleed of this air
How is the correct amount of air in an oleo strut determined
By the amount the strut extends out of the cylinder when the weight of the aircraft is on it
What is the purpose of a compensator port in the master cylinder of aircraft brakes
The compensator port in the master cylinder opens the brake reservoir to the wheel cylinder when the brakes are off. This prevents pressure building up in the brake lines and causing the brakes to drag
What are the two basic types of hydraulic fluid that are used in modern aircraft
Mineral base fluid and phosphate Ester base fluid
What does unloading valve do in a hydraulic system
The unloading valve, or pressure,controls systems pressure by shifting the pump outlet fluid from the pressurized systems back into the reservoir when the systems pressure is high enough. The fluid cirulates with very little load on the pump until the system pressure drops to the regulator kick-in valve. The pump then forces fluid into the system until the pressure builds back up to the regulator kickoff valve
What is the purpose of an orifice check valve in an aircraft hydraulic system
An orifice check valve allows full flow of fluid in one direction through the valve but restricts it in the opposite direction
What is meant by a single action hydraulic actuation cylinder
A linear actuation cylinder that uses Hydraulic fluid under pressure to move the piston in only one direction. The piston is returned by a spring
What kind of device is used to control the speed of movement of the position in a pneumatic actuator
A variable orifice
What is the difference between an open center selector valve and a close center valve
Open center selector valves are installed in series with each other, and the hydraulic fluid flows through their center when no component is being actuated.
Closed center selector valve are installed in parallel with each other they direct fluid under pressure to one side if the actuator and fluid from the other side of the actuator to the system return manifold. In the off position, they trap fluid in the lines between Tha. Alve a d the actuator
What is used to flush a hydraulic system that sues mineral base hydraulic fluid
Alcohol
Where can you find the type of hydraulic fluid that is required for particular aircraft
In the maintenance manual of the aircraft. This information is also on a placard on the system reservoir
What is used to remove phosphate Ester base hydraulic fluid from aircraft tires
Soap and water