Oil System

Proper lubrication of the engine is essential to the extension of engine life and prevention of excessive maintenance.

The oil system provides a means of storing and circulating oil throughout the in­ternal components of the engine. Lubricating serves two purposes: (1) it furnishes a coating of oil over the surfaces of the moving preventing direct metal-to-metal contact and the generation of heat, and (2) it absorbs and dissipates, through the oil cooling stem, part of the engine heat produced by the internal combustion process.

Usually the engine oil is stored in a sump at the bottom of the engine crankcase. An opening to the oil sump is provided through which oil can be added and a dip stick is provided to measure the oil level in the sump.

A pump forces oil from the sump to the various parts of the engine that require lubrication. The oil then drains back to the sump for recirculation.

1. What is the function of the oil system?

2. What is a dipstick?

3. Why is a loss of ой pressure so dangerous?

4. Why is it important to check the ой level before each flight?

5. What is the function of a fuel selector assembly?

6. Where are usually fuel tanks mounted?

7. What is the function of an auxiliary electric driven pump?

Anti-icing system is designed to prevent ice formation on aircraft vital areas vital areas and permits aircraft operation without restriction by icing conditions. The aircraft ice protection is provided by heating of critical areas (engine air intakes, leading edge, windshields, pitot tubes, static ports, etc.) using hot air or electrical power.

Air conditioning and pressurization system provides maintaining the air in the pressurized compartments at the desired level of pressure, temperature and freshness. The required bleed air for the system is supplied either by engine compressors or APUor a high pressure ground air supply unit.

Each engine is equipped with an oil pres­sure gauge and an oil temperature gauge which are monitored to determine that the oil system is functioning properly.

The oil pressure indication varies with the temperature of the oil. If the oil temperature is cold the pressure will be higher than if the oil is hot.

A loss of oil pressure is usually followed by engine failure. If this occurs while on the ground, the pilot must shut the engine down immediately; if in the air, land at a suitable emer­gency landing site.

It is important to check the oil level be­fore each flight. Starting a flight with an insuffi­cient oil supply can lead to serious conse­quences. The airplane engine will burn off a cer­tain amount of oil during operation, and begin­ning a flight when the oil level is low will usually result in an insufficient supply of oil before the flight terminates.

A more sophisticated aircraft is equipped with some other vital systems: hydraulic system, air conditioning and pressurization system, anti-icing (or de-icing) system, fire extinguishing system, and galley equipment.

The bleed air is cooled, conditioned and distrib­uted to the individual compartments (flight com­partment, passenger compartments and cargo compartments) and then discharged overboard through outflow valves.

Hydraulic system is designed to oper­ate undercarriage, wheel brakes, nose wheel steering, control surfaces, etc. This system is normally divided into at least two systems with maximum degree of independence. Each system comprises engine driven pumps, accumulators, valves, heat exchangers and filters. A non-inflammable liquid is the usual working fluid.

1. What is anti-icing system designed»for?

2. How is aircraft ice protection provided?

3. What is the function of air conditioning and pressurization system?

4. What is hydraulic system designed for?