PP 16

Two types of compressors most commonly used in jet engines are. Cenrigual & axial. Scroll & rotary.

A turboprop propeller. Accounts for 75-85% of the total thrust outptut. Accounts for less than 50% of total thrust.

Where do stress rupture cracks usually appear on turbine blades of turbojet engines. Across the l. edge and trail. edge at a right angle of the edge. Only along the leading edge.

In which type of turbine engine combustion chamber is the case and line removed and installed as one unit during routine maintenance?. Can-annular. Annular reverse flow.

Which of the following are the most common types of thrust reverses used on turbine engine powered aircraft?. Mechanical & aerodynamic blockage. Pneumatic & hydraulic blockage.

When the leading edge of a 1st stage turbine blade is found to have stress rupture cracks, which of the following should be suspected. Over temp. condition. Excessive vibration.

Which of the ff. is the ultimate limited factor of turbojet engine operation?. Tit. N1 rpm.

How is the turbine shaft usually jointed to the compressor rotor of a centrifugal compressor turbine engine. Splined coupling. Bolted flange.

Which of the ff. eng. variables is the most critical during turb. eng operation** a) Tit b) Oil pressure **Respuesta: a**. Tit. Oil pressure.

What should be done if a turb. Eng catches fire during starting?. Turn off the fuel & continue cranking. Increase airflow and add more fuel.

What unit in a gas turbine eng aid in stabilization of the compressor during low thrust engine. Bleed air valves. Ignition exciters.

Dirty compressor blades in a turn eng should result in a. High egt. Low oil temperature.

The exhaust section of turb eng is designed to. Impart a high exit velocity to the exh gases. Cool the exhaust gases before exit.

How many igniters on a turb eng. having nine burner. 2. 1.

What type of oil system is usually found on turbo jet eng. Dry sump, pressure and spray. Wet sump, splash type.

A turbine engine dry-sump lubrication system of the self-contained, high-pressure design. Consist of pressure, breather and scavenge sub-systems. Has only pressure and return pumps.

What type of oil pump is most commonly used turbojet engines. Gear. Vane.

In what units are the turbine engine tachometers calibrated. Percent of engine rpm. Rpm × 100.

The type of ignition system used on most jet aircraft engines is. Capacitor discharge. Magneto discharge.

Which type of fuel nozzles are used in turbine engine combustion chambers. Simplex & duplex. Airblast & pressure swirl only.

What will be the probable result if the oil system pressure relief valve should stick in the open position on a turbine engine?. Insufficient lubrication. Excessive oil pressure.

When trimming a turbine engine, the fuel control is adjusted to. Limit idle rpm and max speed. Increase acceleration time.

Advantage of axial flow compressor. High peak effeciences from ram - high pressure attainable by add-on of compressor stages - small frontal area. Low cost and low maintenance.

Advantage of air starter over an electric air starter. It’s high power – weight ratio. It requires no air source.

Oil line between the scavenge pump and oil breaks, where does the oil go. Dumps overboard. Collects inside the turbine case.

High exhaust temp. with normal EPR for t/off. What is the problem?. Obstructed or damaged turbine section. Fuel control set too low.

Ignition is measured in. Joules. Ohms.

High by-pass ratio of fan to engine. 4:1. 1:1.

Amt. of combustion air used to drive prop on turbo prop engine. 1/3 of energy to frive free turbine. 1/2 of available energy.

Continuous fire loop, how does it work?. The loop is filled with a special ceramic that conducts electrivity only when heated. The loop melts and completes a circuit.