An aircraft flying in conditions of continuous heavy rain and high ambient temperatures may require the precautionary use of ?
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The engine type represented in the drawing is a 951 ?
When the combustion gases pass through a turbine the ?
Regarding a jet engine i the maximum thrust decreases as pressure altitude increases ii the specific fuel consumption inversely proportional to pressure altitude at constant tas I correct, ii correct, i incorrect, ii correct, i correct, ii incorrect, i incorrect, ii incorrect. jet engines are more efficient at higher altitudes because less fuel needed a given thrust, due to reduction in lift drag, lower temperatures through inlet cause a significant reduction in specific fuel consumption, up to tropopause. specific fuel consumption the amount of fuel burnt per unit of thrust. for jets, it reduces with altitude up to tropopause. 
Regarding a jet engine i the maximum thrust increases as pressure altitude decreases ii the specific fuel consumption proportional to pressure altitude at constant tas I correct, ii incorrect, i incorrect, ii correct, i correct, ii correct, i incorrect, ii incorrect. jet engines are more efficient at higher altitudes because less fuel needed a given thrust, due to reduction in lift drag, lower temperatures through inlet cause a significant reduction in specific fuel consumption, up to tropopause. specific fuel consumption the amount of fuel burnt per unit of thrust. for jets, it reduces with altitude up to tropopause. 
One of advantages of an annular combustion chamber A reduced thermal stress on turbine, that fewer igniters are required, a higher structural strength, a simpler assembly. A combustion chamber a very complex structure with its divergent convergent passages. compare to old multi can combustion system, annular combustion chamber are shorter, lighter, cheaper with improved combustion characteristics, more power greater efficiency. the main driver in combustion chamber development the need to equalise temperature flow around whole turbine entry ring in order to reduced thermal stress. 
The correct order of decreasing freezing points of three mentioned fuels Jet a, jet a, jet b, jet b, jet a, jet a, jet a jet a, jet b, jet b, jet a, jet a. The accepted minimum fuel temperature safe flight for jet a 40°c jet a 1 47°c jet b 65°c. Question Turbine Engines 32 Answer 8
Labyrinth seals in lubrication system of a gas turbine engine are designed to provide a seal that Not completely tight, allowing some movement between rotating static parts, not completely tight, allowing only some radial movement between rotating static parts, completely tight, allowing no movement between rotating static parts, completely tight, allowing some axial movement between rotating static parts. Question Turbine Engines 32 Answer 9
Regarding a jet engine i the maximum thrust decreases as pressure altitude increases ii the specific fuel consumption decreases slightly as pressure altitude increases at constant tas I correct, ii correct, i incorrect, ii correct, i correct, ii incorrect, i incorrect, ii incorrect. Jet engines are more efficient at higher altitudes because less fuel needed a given thrust, due to reduction in lift drag, lower temperatures through inlet cause a significant reduction in specific fuel consumption, up to tropopause. specific fuel consumption the amount of fuel burnt per unit of thrust. for jets, it reduces with altitude up to tropopause. Question Turbine Engines 32 Answer 10
The characteristics of an axial compressor are 1 a low pressure ratio stage2 a high pressure ratio stage3 possibility of compressing a large mass airflow4 inability of compressing a large mass airflowthe combination that regroups all of correct statements , 3,, 4, 2, 3, 3, 4. the key word here by stage! a centrifugal compressor will produce about 5 1 ratio per stage (ie impeller & diffuser) compared to a axial that gives about 1,2 1 per stage. however use of multi stage axial compressors gives a bigger overall ratio. Question Turbine Engines 32 Answer 11
Which of following statements correct about flow in a divergent subsonic gas turbine engine intake i the speed decreases in flow direction ii the total pressure remains constant in flow direction I correct, ii correct, i incorrect, ii correct, i correct, ii incorrect, i incorrect, ii incorrect. There a velocity decrease as air flows from a small inlet to a larger outlet. Question Turbine Engines 32 Answer 12
Which of following statements correct about flow in a divergent subsonic gas turbine engine intake i the static pressure increases in flow direction ii the total temperature remains constant in flow direction I correct, ii correct, i incorrect, ii correct, i correct, ii incorrect, i incorrect, ii incorrect. In a divergent duct with subsonic flow, static pressure rises as does static temperature, but total temperature remains constant. Question Turbine Engines 32 Answer 13
Which of following statements correct about flow in a divergent subsonic gas turbine engine intake i the dynamic pressure decreases in flow direction ii the static temperature increases in flow direction I correct, ii correct, i incorrect, ii correct, i correct, ii incorrect, i incorrect, ii incorrect. Question Turbine Engines 32 Answer 14
A flat rated turbofan engine has a constant maximum rated thrust level Up to a specific oat, up to a specific pressure altitude, above a specific oat, above a specific pressure altitude. the term flat rating so called because of flat nature of thrust versus ambient temperature curve. the curve shows that from lowest operating temperature possible to specified temperature, engine produces full thrust. above this temperature, full thrust will not be permitted. a 'flat rate turbofan engine controlled in such a way that at constant ambient air pressure there no variation of take off thrust with air temperature up to some specified temperature limit. above that limit engine operates in such a way that either fan speed or compressor speed constant or turbine inlet temperature constant and in either case thrust then decreases with increasing temperature. Question Turbine Engines 32 Answer 15
Which of following statements correct about flow in a divergent subsonic gas turbine engine intake i the dynamic pressure decreases in flow direction ii the static temperature decreases in flow direction I correct, ii incorrect, i incorrect, ii correct, i correct, ii correct, i incorrect, ii incorrect. Question Turbine Engines 32 Answer 16
Which of following statements correct about flow in a divergent subsonic gas turbine engine intake i the speed remains constant in flow direction ii the total pressure decreases in flow direction I incorrect, ii incorrect, i incorrect, ii correct, i correct, ii incorrect, i correct, ii correct. The speed flow reduced. static pressure increases, dynamic pressure decreases total pressure remains unchanged. there no total temperature changes, but static temperature increases while dynamic temperature decreases. Question Turbine Engines 32 Answer 17
Which of following statements correct about flow in a divergent subsonic gas turbine engine intake i the static pressure remains constant in flow direction ii the total temperature decreases in flow direction I incorrect, ii incorrect, i incorrect, ii correct, i correct, ii incorrect, i correct, ii correct. Static pressure increases, dynamic pressure decreases total pressure remains unchanged. there no total temperature changes. Question Turbine Engines 32 Answer 18
Which of following statements correct about flow in a divergent subsonic gas turbine engine intake i the dynamic pressure remains constant in flow direction ii the static temperature remains constant in flow direction I incorrect, ii incorrect, i correct, ii correct, i correct, ii incorrect, i incorrect, ii correct. Static pressure increases, dynamic pressure decreases total pressure remains unchanged. there no total temperature changes, but static temperature increases while dynamic temperature decreases. Question Turbine Engines 32 Answer 19
Which statement correct about flow in a divergent jet engine inlet i the speed increases in flow direction ii the total pressure increases in flow direction I incorrect, ii incorrect, i incorrect, ii correct, i correct, ii incorrect, i correct, ii correct. The flow speed decreases. static pressure increases, dynamic pressure decreases total pressure remains unchanged. Question Turbine Engines 32 Answer 20
Which of following statements correct about flow in a divergent subsonic gas turbine engine intake i the static pressure decreases in flow direction ii the total temperature increases in flow direction I incorrect, ii incorrect, i incorrect, ii correct, i correct, ii incorrect, i incorrect, ii correct. Static pressure increases, dynamic pressure decreases total pressure remains unchanged. there no total temperature changes, but static temperature increases while dynamic temperature decreases. Question Turbine Engines 32 Answer 21
Which of following statements correct about flow in a divergent subsonic gas turbine engine intake i the dynamic pressure increases in flow direction ii the static temperature decreases in flow direction I incorrect, ii incorrect, i incorrect, ii correct, i correct, ii incorrect, i correct, ii correct. Static pressure increases, dynamic pressure decreases total pressure remains unchanged. there no total temperature changes, but static temperature increases while dynamic temperature decreases. Question Turbine Engines 32 Answer 22
Both gas turbine and piston engines use a cycle made up of induction compression combustion and exhaust phases which of these statements about a gas turbine are correct or incorrect i the process in a gas turbine engine continuous ii theoretically combustion occurs at constant pressure I correct, ii correct, i incorrect, ii incorrect, i incorrect, ii correct, i correct, ii incorrect. Piston engine combustion process intermittent, governed the rythm of back forth movements of piston in a cylinder. the combustion occurs at constant volume in cylinder. turbine engine combustion process continuous occurs at constant pressure. Question Turbine Engines 32 Answer 23
A twin spool engine with an inlet air mass flow of 220 kg/s and a hp compressor mass flow of 220 kg/s has a bypass ratio of bypass ratio = bypass mass flow / hp compressor mass flow 220 220 = 0 0/220 = 0 bypass ratio = 0 Question Turbine Engines 32 Answer 24
A turbofan engine with an inlet air mass flow of 200 kg/s and a hp compressor mass flow of 20 kg/s has a bypass ratio of bypass ratio = bypass mass flow / hp compressor mass flow 200 20 = 180 180/20 = 9 Question Turbine Engines 32 Answer 25
A turbofan engine with an inlet air mass flow of 220 kg/s and a hp compressor mass flow of 20 kg/s has a bypass ratio of bypass ratio = bypass mass flow / hp compressor mass flow 220 20 = 200 200 / 20 = 10 Question Turbine Engines 32 Answer 26
A turbofan engine with a bypass air mass flow of 200 kg/s and a hp compressor mass flow of 20 kg/s has a bypass ratio of bypass ratio = bypass mass flow / hp compressor mass flow 200/20 = 10. Question Turbine Engines 32 Answer 27
A turbofan engine with an inlet air mass flow of 220 kg/s and a bypass mass flow of 200 kg/s has a bypass ratio of bypass ratio = bypass mass flow / hp compressor mass flow 220 200 = 20 200 / 20 = 10 Question Turbine Engines 32 Answer 28
The throttle lever angle tla information of a fadec controlled gas turbine engine provided To electronic engine control unit a direct electrical wiring connection, to hydro mechanical main engine control, via cables pulleys, to a single dedicated channel of fadec. Tla (thrust lever angle) indicates position of thrust lever in control stand from a reference point, usually this 0° when thrust lever at idle increases up to 40° when thrust lever advanced to take off position. this thrust lever connected mechanical linkages to an electrical resolver synchro sensor called thrust lever angle resolver.the resolver has a stator rotor,the angle of rotor with respect to stator reference point changes as thrust lever moved, this angle called thrust lever resolver angle (tra). this resolver connected to electronic engine control(eec) to control engine thrust different positions of thrust lever. Question Turbine Engines 32 Answer 29
A twin spool engine with a bypass mass flow of 250 kg/s and a hp compressor mass flow of 250 kg/s has a bypass ratio of bypass ratio = bypass mass flow / hp compressor mass flow 250 / 250 = 1 Question Turbine Engines 32 Answer 30
Which of following statements regarding variable inlet guide vanes vigvs and variable stator vanes vsvs on a high bypass engines correct Vigvs are located at front of hp compressor and, together with vsvs, control compressor airflow, vigvs are located in front of fan control both fan compressor air flow. vsvs are used in compressor only are used to increase pressure ratio, vigvs prevent lp compressor stall vsvs prevent hp compressor stall, if vigvs move towards open position, vsvs move towards closed position. The compression system usually split into two units a low pressure (lp) compressor mounted on one shaft followed an high pressure (hp) compressor mounted on hp shaft driven its own (hp) turbine. the fan blades of general electric engine on a boeing 747 800. behind fan, compressor inlet guide vanes (inner circle) variable stator vanes (outer circle) can be seen. Question Turbine Engines 32 Answer 31
A turbofan engine with an inlet air mass flow of 300 kg/s and a hp compressor mass flow of 50 kg/s has a bypass ratio bypass ratio = bypass mass flow / hp compressor mass flow 300 50 = 250 250 / 50 = 5 Question Turbine Engines 32 Answer 32
A turbofan engine with a bypass mass flow of 250 kg/s and a hp compressor mass flow of 50 kg/s has a bypass ratio of bypass ratio = bypass mass flow / hp compressor mass flow hp compressor mass flow = 50 bypass = 250 250 / 50 = 5 Question Turbine Engines 32 Answer 33
A turbofan engine with an inlet air mass flow of 300 kg/s and a bypass mass flow of 250 kg/s has a bypass ratio of bypass ratio = bypass mass flow / hp compressor mass flow inlet = 300 bypass = 50 hp compressor mass flow 300 50 = 250 bypass ratio = 250 / 50 = 5 Question Turbine Engines 32 Answer 34
A turbofan engine with a bypass mass flow of 888 kg/s and a hp compressor mass flow of 111 kg/s has a bypass ratio of bypass ratio = bypass mass flow / hp compressor mass flow 888 / 111 = 8 Question Turbine Engines 32 Answer 35
Bleeding air from hp compressor of a turbofan whilst maintaining thrust increases Egt fuel flow, hp compressor discharge pressure n2, n2 fuel flow, egt n. oscarjp if there less air flow coming in, egt will rise in function of that because there a loss on efficiency due to bleed more work demanded to system so fuel flow increases. Question Turbine Engines 32 Answer 36
A twin spool engine with an inlet air mass flow of 500 kg/s and a bypass mass flow of 250 kg/s has a bypass ratio bpr of bypass ratio = bypass mass flow / hp compressor mass flow inlet = 500 bypass = 250 > compressor = 250 250 / 250 = 1. Question Turbine Engines 32 Answer 37
Compressor stall due to An excessively high angle of attack of rotor blades, an excessively low angle of attack of rotor blades, an excessively high axial velocity, an inadequate fuel flow. Like stall of a wing, compressor stall caused a breakdown of airflow. if your wing suitable high speed, you fly at low speed large angle of attack, stall most likely to occur. a compressor stall most likely to occur when air flow stagnates in rear stages of compressor. a compressor blade hitting oncoming airflow at an angle of attack that determined a combination of rotational speed the incoming airflow. when incoming speed low angle of attack will be high. when angle of attack gets too high blade stalls. so when axial flow in a compressor backs up blades stall (pressure increase in rear stages this slows down flow). you can prevent this dumping some late stage air to atmosphere (via bleed valves). Question Turbine Engines 32 Answer 38
A turbofan engine with an inlet air mass flow of 1000 kg/s and a hp compressor mass flow of 111 kg/s has a bypass ratio of bypass ratio = bypass mass flow / hp compressor mass flow bypass mass flow = 1000 111 = 889 889 / 111 = 8.01 Question Turbine Engines 32 Answer 39
Which of these statements about an reaction turbine are correct or incorrect i the pressure drops across nozzle guide vanes ii the pressure remains constant across rotor blades I correct, ii incorrect, i correct, ii correct, i incorrect, ii correct, i incorrect, ii incorrect. There a pressure drop a velocity increase across stator of a reaction turbine. Question Turbine Engines 32 Answer 40
The electronic engine control of a fadec gas turbine engine checks All input output data, active channel input output data only, input data only, output data only. The full authority digital engine control system (fadec) receives all necessary data engine operation takes over virtually all of steady state transient control functions, which includes compressor airflow control (vigv's, vsv's, etc).
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