Engineering Flashcards
If you have a total AC power failure, and get a Generator back on line, what will give you and indication of its power output?
Kilowatt Meter.
What does a diffuser do?
A diffuser is simply a divergent duct that slows the velocity of the impeller’s output air; thereby, increasing the air pressure before it enters the combustion chamber.
What is the purpose of a hydraulic accumulator?
Hydraulic accumulators store pressure in order to provide backup for key operations in the event of a pump failure. They normally consist of a sealed pressure container with a diaphragm or piston installed. System hydraulic pressure compresses nitrogen or dry air to store energy for a short application of power in the event of a pump failure. Accumulators may also be used to control fluctuation or surges in the system.
Which section of the engine has the highest pressure in turbojet engine?
The diffuser section between the compressor and the combustion section.
What converts AC to DC?
Transformer Rectifier (transformer changes the frequency, and the rectifier changes the AC to DC).
What are the effects of a blocked static port?
The airspeed indicator may still function but could product inaccurate indications. At the attitude where the blockage occurs, airspeed indication would be normal. At higher altitudes, the ASI will indicate lower, at lower altitudes, the ASI would indicate higher. The trapped pressure causes the altimeter to remain at the altitude where the blockage occurred. The VSI remains at zero.
If the pitot head is blocked but the drain hole and static port are not, what happens to airspeed?
Indication will drop to zero. With no pressure in the lines, the airspeed drops to zero since the pitot pressure will be roughly equal to the static pressure.
The best performance for a turbine engine is?
The turbojet engine has a strong preference for high RPM to produce low specific fuel consumption. Combined with high altitudes, a turbine engine will maximize range and endurance using altitude, higher TAS and high engine RPM to achieve the most efficient operation.
What is the sequence for starting a turbine engine?
Air, Ignition, Fuel
Which laws relate to the development of thrust in any powerplant?
Newton’s laws of motion. More specifically, the second law; a body of mass “m” subject to a net force “F” undergoes an acceleration “a” that has the same direction as the force and a magnitude that is directly proportional to the force and inversely proportional to the mass, i.e., F=ma. The third law; for every action there is an equal and opposite action.
What is EPR?
EPR, or Engine Pressure Ratio, is the ratio of turbine discharge pressure divided by the compressor inlet pressure. EPR is used as an indication of the amount of thrust being developed by a gas turbine engine.
Which place is a turbojet engine is subjected to the highest temperatures?
The highest temperature will occur in the turbine inlet.
What instruments are affected by a blocked static port?
The altimeter, the vertical speed indicator and the air speed indicator.
What is the corrective action for a compressor stall?
A recovery must entail reduction of throttle setting to reduce fuel flow, lowering the angel of attack and sideslip and increasing airspeed to improve inlet condition and reducing altitude if high altitude is a contributing factor.
What will the EPR indications be after a bleed source is turned on?
They will read lower from 0.03 for Packs to 0.08 for Engine Anti-Ice and 0.04 for Wing Anti-Ice.
