ATPL Aerodynamics & Systems Exam 1

Questions and Answers

Which does not affect hydroplaning speed?

Tyre pressure

Tread wear

Tyre size (correct)

Tread pattern

Which RPM range will produce the greatest variation in thrust for a given movement of the power lever?

The upper end of the RPM range (correct)

The lower end of the RPM range

The middle of the RPM range

No particular RPM range

What is a function of a pressure relieve valve in a transport category jet hydraulic system?

To prevent hydraulic jack stall

To prevent hydraulic lock

To prevent hydraulic seals from blowing out

To regulate the normal system operating pressure (correct)

What is the function of the rear turbine support struts in the exhaust system of a turbojet engine?

To support the propelling nozzle Signup and view all the answers

In a gas turbine engine, what happens when the start bleed valve is open at idle RPM and the RPM is then increased to maximum?

The EGT will be higher than normal with reduced thrust output Signup and view all the answers

Where are the nozzle guide vanes (NGVs) in a gas turbine engine located?

At the turbine inlet Signup and view all the answers

The effect of spoiler deployment on the total drag curve for an aeroplane is to move the curve:

Up and right Signup and view all the answers

On an aircraft with a conventional flight director system, the flight director bars are controlled by:

The flight director computer Signup and view all the answers

What is the primary advantage of AC over DC electrical generation types?

Savings on space and weight Signup and view all the answers

An aircraft is fitted with NiCad batteries, and the crew get a 'High Battery Temp' warning light. This situation was probably caused by:

The rate of charging was too high Signup and view all the answers

After a wet start in a turbine engine, what precautions should be taken to prevent a future engine malfunction?

Use a cross-bleed start to prevent a hot start Signup and view all the answers

With increasing airspeed up to and beyond Mach 1.0, the coefficient of drag at a constant angle of attack will:

Initially increase, then decrease Signup and view all the answers

The purpose of a cabin pressure relief valve is to automatically open when:

The cabin rapidly depressurizes, such as in an explosive decompression Signup and view all the answers

The valve that controls the air pressure in a cabin pressurization system is known as:

The outflow valve Signup and view all the answers

Which of the following correctly names the component in a pneumatic system that will automatically shut off the air supply to non-essential services when system pressure reduces below a certain predetermined value?

Isolation control valve Signup and view all the answers

In what way is the specific gravity (SG) of AVTUR affected by changes in ambient temperature?

SG decreases with temperature rise Signup and view all the answers

Under which of the following conditions is it necessary to incorporate cabin air humidifiers in an aircraft air conditioning system?

When operations are at low altitudes/low temperatures Signup and view all the answers

Hydraulic fluid has which of the following properties?

It is almost incompressible Signup and view all the answers

When comparing the properties of pneumatic vs hydraulic systems:

Pneumatics do not require return lines, whereas hydraulic systems do Signup and view all the answers

In what way does the extension of leading edge devices such as flaps and slats affect the coefficient of lift and drag and the nose pitching moment?

Increase in lift and drag coefficient, and a nose up pitch moment Signup and view all the answers

Assuming the same degree of trailing edge flap deflections, which answer best describes the primary advantage of slotted flaps compared to Fowler flaps?

Improved boundary layer airflow over flaps Signup and view all the answers

Assuming the aircraft is within the various radio altitude envelope bands, in which of the following scenarios will the flight crew receive a warning?

When 1 dot or more below the glideslope Signup and view all the answers

Assuming a constant speed drive is disconnected in flight, when and under what circumstances can it be re-connected?

Electrically, when the undercarriage air/ground logic switch has weight on it Signup and view all the answers

Which of the following best describes how an APU speed is controlled?

By a governor Signup and view all the answers

The device that controls the direction of movement of a hydraulic actuating unit is called the:

Selector valve Signup and view all the answers

Which of the following switches must be closed before a generator can be connected to the synchronizing bus?

The generator circuit breakers switch Signup and view all the answers

Which answer best describes the disadvantage of a turboprop engine compared to a turbojet engine?

Lower propulsive efficiencies at high subsonic Mach numbers Signup and view all the answers

The Auto-land Status Enunciator:

Monitors autopilot and ILS ground station signal integrity Signup and view all the answers

A swept wing transport turbojet is cruising at a higher than normal operating altitude, at normal cruise Mach number, in non-turbulent conditions. It experiences buffet, which statement is most correct?

It could be high or low speed buffet, as it is difficult to tell at high altitude Signup and view all the answers

Shock waves can form at a true Mach number below Mach 1.0. This is because:

Curved surfaces in various parts of the aircraft accelerate the airflow to greater than free stream Mach number Signup and view all the answers

A control tab that is moved by the main control linkage, such that the hinge moments cause a deflection of the primary control surface. This device is called a:

Servo Tab Signup and view all the answers

High flying air transport aircraft have a fuel tank venting system. This is to:

Ensure the tank walls do not rupture when in turbulence, or during maneuvers Signup and view all the answers

What is the reason why the hydraulic reservoir is pressurized in high-flying aircraft?

To prevent the fluid from foaming due to low ambient pressures at high altitudes Signup and view all the answers

An aircraft is fitted with TCAS and GPWS. Which statement is most correct?

GPWS warnings are inhibited if a TA or RA occurs Signup and view all the answers

The B767 incorporates a typical Autopilot Flight Director Systems (AFDS). When an ILS is being flown, with the ‘ALTITUDE HOLD’ and ‘APPROACH’ modes selected, which statement best represents the actions that follow?

The system is armed to capture the glide-slope, and ‘ALTITUDE HOLD’ will automatically cancel when this occurs Signup and view all the answers

The manoeuvre envelope defines:

The speed/load factor limits within which the aircraft is to be operated Signup and view all the answers

‘Manual Reversion’ is provided:

On aircraft that do not have triple hydraulic system redundancy Signup and view all the answers

An aircraft accelerates beyond MCRIT and displays a nose-down tendency. This is due to:

The rearward movement of the Centre of Pressure, and reduced tailplane down-load Signup and view all the answers

On a large transport aircraft, the effect of a failure of the leading edge high lift devices to extend is to:

Require a higher than normal attitude (alpha) and lower airspeed on approach Signup and view all the answers

With an increase in altitude, and same equivalent airspeed (EAS), spiral stability:

Decreases Signup and view all the answers

Which statement is most correct?

The primary function of ground spoilers is to reduce lift and increase braking effectiveness Signup and view all the answers

As the speed of a large transport aircraft increases from low speed stall to M MO, the power requirements during this phase can be best described as:

Non-linear increase Signup and view all the answers

The primary reason for fitting leading and trailing edge flaps is to:

Reduce the landing and take off speeds and distances needed Signup and view all the answers

A number of swept wing jet transport aircraft have a limitation such that flap extension at high altitudes (typically above FL200) is prohibited. This is because:

The high IAS at such altitude can exceed the flap restricting Mach number Signup and view all the answers

With increasing altitude up to maximum cruise level:

Low and high speed stall buffet speed IAS values become closer together Signup and view all the answers

An excessively aft center of gravity when on approach to land will cause:

Light elevator control forces, and decreased pitch stability Signup and view all the answers

The center of gravity is near its forward envelope limit. Which statement is most correct?

Less elevator force is required to change the pitch attitude than with an aft C of G position Signup and view all the answers

As altitude is gained, how is the low speed stall value affected?

IAS value decreases, but EAS value increases cumulatively Signup and view all the answers

A ‘TRIP FREE’ thermal circuit breaker (CB) can be reset:

Only when the overload condition no longer exists Signup and view all the answers

The Zero Fuel Weight (ZFW) limit imposed on some aircraft is to ensure the spar is not overstressed and is:

Relevant at take-off weight Signup and view all the answers

During a climb at a constant Mach number, the angle of attack will:

Increase Signup and view all the answers

In stable asymmetric flight:

Bank and rudder are used in combination to counteract the yaw produced by the live engine Signup and view all the answers

Greater rearward wings sweep:

Reduces trailing edge flap effectiveness Signup and view all the answers

Which of the answers is incorrect about factors assisting lateral static stability?

Inboard flaps Signup and view all the answers

An aircraft fitted with 2 EADI and two EHSI. What is the minimum number of symbol generators required for all screens to be operational?

1 Signup and view all the answers

Which answer listed is correct regarding aircraft system warnings whilst the aircraft is taking off?

Both cautions and warnings are inhibited from 80 knots to 400 ft radio altitude Signup and view all the answers

If the reported wind speed was 20 kt gusting to 40 kt, what would be the appropriate approach speed?

VREF + 20 kt Signup and view all the answers

Hydraulic fluid pumps are lubricated and cooled by:

Hydraulic fluid Signup and view all the answers

If the pilot feels a rapid oscillation through the pedals while operating the antiskid brake system, what is the probable cause?

Antiskid brake system failure and wheel lock up Signup and view all the answers

What element of the antiskid brake system provides protection for the hydraulic system against damage?

The modulator valve Signup and view all the answers

In steady asymmetric flight in a multi-engined aircraft, where will the balance ball be if the wings are level?

Displaced fully toward the live engine Signup and view all the answers

In MAP mode, the altitude range arc on the B767 EHSI display shows:

The computed top of climb position based on current wind and rate of climb Signup and view all the answers

What is the purpose of the bogie wheel landing gear configuration compared to a single wheel?

To permit increased tyre pressures and higher ACNs Signup and view all the answers

Regarding inertial reference systems (IRS), which statement is correct?

An IRS can derive current true heading independent of other inputs Signup and view all the answers

What will happen with differential spoilers fitted to an aircraft when a left bank is initiated?

The left spoiler will retract if both were extended Signup and view all the answers

What method is usually used when charging lead-acid batteries in an aircraft?

Constant current Signup and view all the answers

When an autopilot system ‘mimics’ control wheel inputs, it is connected in:

Parallel Signup and view all the answers

In monitoring autopilot systems via the auto-land status enunciator, what does a land 2 indication mean?

Any single fault would not prevent the autopilot system from making an automatic landing (fail operational) Signup and view all the answers

Why does a particular aircraft demonstrate good oscillatory stability at 1000 ft but poor stability at 30000 ft?

Reduced aerodynamic authority (damping) at altitude due to increased TAS as a result of a decrease in density Signup and view all the answers

When configured for take-off, the command speed bug on the airspeed indicator is referenced to:

VREF Signup and view all the answers

If a transport category aircraft crew forgets to load a descent point in the FMC, what will happen when it passes the last programmed waypoint with LNAV engaged?

Maintain present track Signup and view all the answers

To provide LNAV guidance, the FMC requires navigation data from:

2 IRS's Signup and view all the answers

In asymmetric flight, how is a multi-engined piston propeller-driven airplane usually flown?

Bank away from the dead engine with no sideslip and the ball slightly off center toward the live engine Signup and view all the answers

Air is slowed down in the combustion chamber of a gas turbine engine to:

Confine the heat to a smaller region Signup and view all the answers

When thermocouples are used in parallel to measure temperature in a jet engine, what will the temperature shown be?

The maximum temperature of all probes on the circuit Signup and view all the answers

The formula 'nine times the square root of the tyre pressure in PSI' gives the:

Maximum speed for hydroplaning in knots Signup and view all the answers

What is expected if ‘AILERON LOCKOUT’ appears as a caution message on the EICAS?

Degraded roll controllability at low speeds Signup and view all the answers

The fast/slow indicator on a conventional attitude indicator shows speed as fast or slow relative to:

The command bug speed Signup and view all the answers

If the EPR probe at the compressor inlet of a jet engine becomes blocked with ice during taxiing and the thrust levers are advanced for takeoff, what is the most probable result?

The EPR gauge will underread and engine thrust will be less than takeoff thrust Signup and view all the answers

Regarding cabin altitude warnings and oxygen mask deployment in jet transport category aircraft, which statement is correct?

Cabin altitude warning at 10000 ft, oxygen mask deployment at 14000 ft Signup and view all the answers

If the FMC detects a discrepancy between the computed fuel quantity and the indicated fuel quantity, what will it do?

Alert the pilot(s) of the discrepancy with a fuel quantity error message Signup and view all the answers

What are the advantages of a tricycle undercarriage configuration?

Greater braking effectiveness, better visibility during landing and taxiing Signup and view all the answers

What minimum inputs are required to initialize an inertial navigation system?

Latitude, longitude and time Signup and view all the answers

What is the auto-flight mode combination that controls thrust to maintain a set aircraft speed?

VNAV PATH and SPD Signup and view all the answers

If the pilot rolls the control column towards the right to initiate a right turn with differential flight spoilers used, what will happen?

If the spoilers are extended, the left spoiler will retract and the right spoiler will remain extended Signup and view all the answers

Regarding ground steering for large transport category aircraft, what is true about the rudder pedals and tiller usage?

Full tiller deflection gives a greater angle of nose-wheel steering than full rudder pedal deflection Signup and view all the answers

What is the incorrect statement regarding the use of brakes on large aircraft?

With overheated brakes, a takeoff is allowed immediately after prolonged taxiing as long as excessive brake pressure is not applied Signup and view all the answers

In large transport category aircraft with multiple batteries, how are they usually connected?

Parallel to increase the current at constant voltage Signup and view all the answers

What types of errors are associated with a Machmeter?

Temperature, compressibility, pressure and position Signup and view all the answers

In a split bus electrical system with two main engine-driven generators, what is a true statement?

A bus is only supplied by one generator at any given time Signup and view all the answers

What components make up the Master Warning system on an aircraft?

Audio alarm and a light on the glare shield Signup and view all the answers

What gauge is essential in monitoring a parameter critical to pressurization in a pressurized aircraft?

The cabin altitude and differential pressure gauge Signup and view all the answers

Standpipes in a jet transport aircraft hydraulic system are needed to:

Ensure a positive supply of fluid to the pump during periods of high demand Signup and view all the answers

Compared to a high bypass turbofan, what characterizes a pure turbojet engine?

A higher power to weight ratio Signup and view all the answers

While cruising at a constant flight level at a Mach number of 0.82, how does an increase in ambient temperature affect the aircraft?

A higher TAS and a higher SFC Signup and view all the answers

Methods for defining waypoints entered by the crew into the FMC database include:

Latitude and longitude, place bearing/distance, place distance/place distance Signup and view all the answers

If an aircraft is filled to full tank volume capacity with AVTUR at a specific gravity (SG) of 0.8, what would the available range be if the SG were 0.7 instead?

Less Signup and view all the answers

Concerning large aircraft electrical systems, what is true about split bus systems?

In a split bus system, one generator will never supply power to all services Signup and view all the answers

In an aircraft electrical system, what is a bus bar?

A large terminal for power distribution to services Signup and view all the answers

In the B767-300ER autopilot system, what condition prevents autopilot engagement?

The heading cursor (bug) is different from the aircraft heading Signup and view all the answers

In a steady climb, how is thrust produced by the engines balanced?

Plus a component of lift Signup and view all the answers

In an aircraft with a ‘flying tail’, movement of the control column results in movement of the:

Tailplane with the elevator moving in the opposite direction Signup and view all the answers

In a turbo-jet aircraft compared to a turbo-prop aircraft, at what points is the lowest specific fuel consumption (SFC) achieved?

High speed Signup and view all the answers

Where is the highest temperature in a gas turbine engine?

In the primary (front) part of the combustion chamber Signup and view all the answers

How is the HOT battery bus powered?

When any battery is connected to the aircraft Signup and view all the answers

Which is NOT an element of anti-skid?

Pneumatic reserve braking Signup and view all the answers

Compared to a turbojet of the same thrust output, how would the high-pressure turbine of a turbofan appear?

Smaller due to the reduced mass airflow Signup and view all the answers

Which one is NOT an air data computer output?

Pitch attitude Signup and view all the answers

What does the nose wheel steering follow-up do?

Commands the steering valve to select the nose-wheel in neutral during gear retraction Signup and view all the answers

What describes the airflow ahead and behind a 'normal' shockwave on a conventional wing section?

Supersonic ahead of the shockwave, sub-sonic behind, with no change in airflow direction Signup and view all the answers

During a climb in a turbojet aircraft, which element is maintained?

Fan speed (N1) Signup and view all the answers

What do vortex generators on a horizontal stabilizer primarily do?

Reduce turbulent flow separation, and preserve elevator authority at all flight speeds Signup and view all the answers

What is the effect of dissolved water in Avtur fuel?

Reduces specific gravity, causes microbial infestations, and sludge Signup and view all the answers

When must tires be replaced?

There is a bulge in the tread Signup and view all the answers

How can air conditioner load on an engine be relieved?

Selecting the re-circulation fans on the air conditioner controller to on Signup and view all the answers

What is the configuration of body gear when fitted?

Turns in the opposite direction to the nose gear to reduce tire scuffing Signup and view all the answers

When is spiral instability worst?

When directional stability is high compared to lateral stability Signup and view all the answers

During climbing at a constant CAS, what do you expect the Mach number and TAS to do?

Mach number to decrease, TAS to increase Signup and view all the answers

What is expected when climbing at a constant speed just below VMO?

The MMO value to eventually be exceeded Signup and view all the answers

How can you reduce the VMCG speed?

Increase the take-off thrust setting, and/or move the C of G forward Signup and view all the answers

How does high-density altitude affect the VMCG speed?

Increase it Signup and view all the answers

With the loss of the right engine, which statement is most correct?

With a bank toward the live engine, less rudder deflection will be needed, and the skid ball will be slightly displaced to the live engine side Signup and view all the answers

What occurs when the left wing-mounted engine fails in aircraft with two engines mounted in pods beneath the wing?

A requirement for pitch up trim, a yaw to the left, right rudder trim required Signup and view all the answers

Regarding factors affecting VMCA, which statement is MOST correct?

Dihedral, banking toward a failed engine, and large tailfin increase VMCA value Signup and view all the answers

Which statement is MOST correct about drag?

Induced drag is highest at the angle of attack for maximum lift Signup and view all the answers

Compared to a conventional wing, where is the position of maximum camber on a laminar flow wing?

Further rearward Signup and view all the answers

In comparing MCRIT and MCDR of a supercritical wing to a conventional cambered wing, how do they differ?

MCRIT is higher, and MCDR lower Signup and view all the answers

Which statement is MOST correct?

Washout is used on swept wings. The angle of incidence is less at the root than at the tips, causing the roots to stall before the tips Signup and view all the answers

What is the best recovery technique for a swept wing aircraft encountering a downdraft shortly after takeoff?

Lower aircraft nose to prevent stall, then zoom climb using high alpha Signup and view all the answers

Which statement best describes the properties of slots and LE flaps?

Slots and slats re-energize the boundary layer, slats and LE flaps increase the camber Signup and view all the answers

What do leading edge devices primarily contribute to?

Contribute most to lift values at high angles of attack Signup and view all the answers

What changes to approach are expected when leading edge devices fail to extend while trailing edges do?

Lower alpha and drag, higher approach speeds, and improved view over the nose Signup and view all the answers

Which statement best describes the properties of a Zap flap?

Increases camber, drag and wing area. Deployment requires nose-up trim change Signup and view all the answers

During a flight over continental Australia in a high capacity RPT aircraft equipped with EFIS and a FMS, the reference for the MAP mode of the EHSI would be:

True Track Signup and view all the answers

What are spoiler panels located at?

Located just ahead of the trailing edge flaps. Deflecting the roll spoilers up on the right wing will see the right wing aileron deflect upwards to initiate a roll to the right Signup and view all the answers

For the park brake to work effectively following the shutdown of all hydraulic systems, at the time of shutdown the brake accumulator pressure must be:

Above minimum brake operating pressure Signup and view all the answers

What happens when shockwaves form?

First over the upper wing at the point of maximum camber. The upper shockwave reaches the trailing edge first due to shockwave induced flow separation on the lower surface Signup and view all the answers

Items monitored by the take-off configuration warning system in a high capacity jet transport aircraft include:

L/E flap position, T/E flap position, stabiliser trim position, spoiler lever position and the park brake valve position Signup and view all the answers

During the ‘ROLLOUT’ submode of an autoland, the IDLE mode of the autothrottle will be:

Disengaged when selecting reverse thrust Signup and view all the answers

What happens as speed increases beyond MCRIT?

The center of lift moves aft, lift reduces, and nose-down pitch moment occurs (Mach tuck) Signup and view all the answers

What is the correct order of events as speed increases?

MCRIT, MDET, MCDR, MFS speed of sound, Mach tuck Signup and view all the answers

Conditional waypoints are entered into the FMC via the:

Init/ref page Signup and view all the answers

What qualities describe the airflow behind a normal shockwave?

Temp and pressure rise, velocity and Mach number decreases, density increases Signup and view all the answers

Subsonic flow through a divergent duct will experience:

Constant density, an increase in pressure, and a decrease in velocity Signup and view all the answers

Supersonic flow through a divergent duct will experience:

A decrease in density and pressure and increasing velocity Signup and view all the answers

How does airflow direction change through shockwaves?

Changes direction through a normal shockwave and an oblique shockwave Signup and view all the answers

In a free-power turbine type engine (turboprop), the free-power turbine is:

Not connected to any other turbine shaft Signup and view all the answers

What happens for high-flying jet aircraft featuring swept wings?

Low speed stall indicated airspeed increases cumulatively as altitude is gained Signup and view all the answers

During CAT III ILS multi-autopilot approach, in the rollout the thrust setting will be:

Flight idle for 5 seconds after touchdown then ground idle Signup and view all the answers

What is the aerodynamic ceiling for a given aircraft?

Lower with increased turbulence/greater bank angle Signup and view all the answers

What does increased apparent gross weight do to speed margin between initial buffet speeds?

Reduces it Signup and view all the answers

The pure turbojet engine design feature which decreased the occurrence of compressor stall was by incorporating:

Variable inlet guide vanes Signup and view all the answers

In terms of SFC and in comparison to a pure turbojet, a turboprop would be more efficient than a turbojet during:

Low speed flight Signup and view all the answers

What is experienced when cruising at high altitude and experiencing buffet?

High or low speed buffet Signup and view all the answers

To ensure correct flow direction is maintained in a hydraulic system, what would you fit?

Check valve Signup and view all the answers

Pressing the CANCEL switch on the EICAS control panel will:

Select the next page Signup and view all the answers

In an aircraft with two separate independent hydraulic systems:

No systems are supplied simultaneously by both systems Signup and view all the answers

Which answer is most correct regarding pneumatic systems?

Pneumatic system is lighter than an equivalent hydraulic system Signup and view all the answers

On an aircraft equipped with both outboard and inboard ailerons, the inboard ailerons operate:

At all times Signup and view all the answers

How do shuttle valves operate?

Automatically should normal system pressure fail Signup and view all the answers

During TCAS operations in TA only mode, RA’s are:

Shown as TA’s Signup and view all the answers

Which answer is incorrect?

The closing of the high pressure bleed shut-off valve at high power settings will automatically open the low pressure valve Signup and view all the answers

What is the ideal humidity for an aircraft cabin?

60% Signup and view all the answers

Airflow behind a normal (vertical) shockwave compared to ahead of the shock will have a decrease in:

Energy (total pressure) Signup and view all the answers

A benefit of a Split Bus type aircraft electrical system is:

There is a reduced requirement for frequency matching Signup and view all the answers

What is the possible humidity level in a high-flying aircraft cabin?

0% Signup and view all the answers

Engine bleed air may be used for:

Reverse thrust actuation, anti-icing, air conditioning and pressurisation Signup and view all the answers

What is the ideal temperature range for humans?

18-24°C Signup and view all the answers

Which statement is most correct regarding bleed air management?

Bleed air source from the engine fan (N1 Low pressure Compressor) is used during low engine rpm and second stage compressor (N2) during high engine RPM Signup and view all the answers

In-flight, engine bleed air for anti-icing the wing leading edges in known icing conditions is:

Used continuously Signup and view all the answers

The radio altimeter display on the EADI is blank when:

Above 2500 ft Signup and view all the answers

Which statement is NOT correct regarding air cycle machines?

Pre-cooler cold air is supplied from the expansion turbine. This is called boot-strapping Signup and view all the answers

To achieve a 'fail operational' autopilot coupled ILS approach in a B767-300ER, when do autopilots engage?

Three autopilots engage at 1500 ft radio altitude Signup and view all the answers

When climbing at a constant Mach number, TAS will:

Decrease in the troposphere then remain constant in the isothermal layer above the tropopause Signup and view all the answers

The reference for the heading display on the EFIS MAP and FMC is:

Either true or magnetic as selected by the pilot or determined by latitude Signup and view all the answers

On an aircraft with a conventional flight instrument panel with two compass systems, the Captain’s HSI displays a HDG flag. In this situation another expected indication would be:

A HDG flag on the First Officer’s RMI Signup and view all the answers

An aircraft with a TAS of 300 kt has a fuel burn of 3000 kg/hr. The Specific Air Range (SAR) as a ratio distance travelled per tonne of fuel used would be most correctly expressed as ratio of:

100 nm/tonne Signup and view all the answers

The EPR of a gas turbine engine may be defined as:

The ratio between the total jet pipe pressure and the total engine inlet pressure Signup and view all the answers

The EGT of a gas turbine engine may be defined as:

The temperature of the gas flow at the exit from the last turbine stage Signup and view all the answers

Windscreen rain repellent fluid is used in some installations to assist visibility. A limitation on its use is:

It should not be used on a dry windscreen as it could smear and reduce forward vision Signup and view all the answers

The first indication of a successful light-off (light-up) in a gas turbine engine is:

Increasing EGT Signup and view all the answers

The main advantage of kerosene compared to wide cut type fuel for use in a gas turbine engine is that kerosene has a relatively:

Lower volatility and higher flash point Signup and view all the answers

A pressurised aircraft on climb maintains its cabin altitude at that of the departure aerodrome until it reaches its maximum cabin pressure differential. If the climb is continued:

The cabin altitude will climb as the system maintains maximum pressure differential Signup and view all the answers

In level flight an AP/FDS mode control panel shows a selected IAS of 280 kt in altitude hold mode. The flight director, autopilot, and auto-throttle are then all turned off. In this case the 280 IAS indication will:

Remain as before but will have no significance on the speed tape display Signup and view all the answers

Reverse thrust is most useful on a large transport turbine aircraft:

At high forward speed in the landing roll Signup and view all the answers

In a gas turbine engine, compressor surge can be recognised by:

Fluctuating RPM Signup and view all the answers

If a reduced thrust take-off is programmed into a flight management computer using the assumed temperature method. Regarding thrust output in the event of an engine failure after V1:

The reduced thrust output from the remaining engines will be sufficient to provide the required climb gradients for obstacle clearance without needing to increase thrust output Signup and view all the answers

The use of sweepback as a design feature of a jet transport aircraft wing will result in:

An increase in MCDR Signup and view all the answers

On a conventional ASI/Mach Meter the Mach readout is covered by a red flag indicating loss of altitude sensing. This means that the Mach display is unreliable and:

The VMO pointer is also probably unreliable Signup and view all the answers

An IVSI differs from a conventional VSI in that it has:

Accelerometers or dashpots to give an immediate indication of climb or descent Signup and view all the answers

An autopilot ‘hardover’ means:

Full servomotor deflection Signup and view all the answers

The purpose of a propeller brake in a turboprop installation is to:

Decelerate the propeller into the ground range after landing Signup and view all the answers

In a normal operation of an aircraft electrical system with a bus tie, the generators are operated:

In parallel Signup and view all the answers

In an aircraft electrical system with two engine driven generators and an APU generator, none of which can be synchronised:

In normal operation, the system operates as a split bus system Signup and view all the answers

The main reason for the combustion of fuel in a gas turbine engine is -

To raise gas temperature Signup and view all the answers

When the residual voltage of a large AC generator decreases to zero and no battery power is available:

It can be restarted if it is a PMG (Permanent Magnet Generator) Signup and view all the answers

When an Integrated Drive Generator (IDG or CSD) suffers an internal failure the unit:

All of the above Signup and view all the answers

With a multiple battery installation in an aircraft, the batteries are usually connected in:

Parallel, to give increased current output at constant voltage Signup and view all the answers

The combustion chamber design which is most cost effective and efficient is the:

Annular design Signup and view all the answers

The percentage of the mass airflow through a gas turbine entering the combustion chamber through the swirl vane is approximately:

12% Signup and view all the answers

When the “THROTTLE HOLD” (THR HLD) mode of the auto-throttle is active and enunciated on the auto-throttle flight mode enunciator on the EADI:

The auto-throttle will adjust to hold the current airspeed Signup and view all the answers

When operating in the region of reversed command (slower than VIMD):

Any decrease in speed will result in increased power required to maintain altitude while an increase in speed will result in less power required to maintain altitude Signup and view all the answers

Which autopilot system isolates the failing autopilot and continues the landing approach in a 'Fail Passive' mode?

3 autopilots Signup and view all the answers

Which description best describes Spiral Stability?

Opposes oscillatory stability and gets better with increased altitude Signup and view all the answers

Which statement is correct about the Diffuser in the exhaust section of a gas turbine engine?

It is a divergent duct increasing gas stream pressure and decreasing gas stream velocity Signup and view all the answers

Which statement correctly describes turbine blade creep stress values with time in service?

Initially during the primary stage and finally in the tertiary stage, blade stretching is significant, being less so between these stages Signup and view all the answers

The function of the positive pressure relief valves in the pressurization system of a transport category aircraft is to:

Limit the maximum positive pressure differential Signup and view all the answers

What is the purpose of the Shuttle Valve in the hydraulic system of a transport category aircraft?

To allow hydraulic pressure from the alternate system to automatically pressurize the lines in the event of a failure of the normal system Signup and view all the answers

In which component of the air cycle machine in the air-conditioning system of a transport category aircraft is the coldest air found?

The expansion turbine Signup and view all the answers

Which of the following components of a hydraulic system in a transport category aircraft acts as a surge suppressor?

The accumulator Signup and view all the answers

The highest temperature in a gas turbine engine is:

In the primary zone of the combustion chamber Signup and view all the answers

In a pure turbojet, compared to a high bypass turbofan of the same thrust output, the rear (LP) turbine wheels are:

Smaller and rotate faster Signup and view all the answers

Regarding factors that affect VMCA which statement is most correct?

Dihedral, banking toward the failed engine and a large tail fin increase VMCA values Signup and view all the answers

A method of reducing the engine air bleed load in an air cycle air conditioning system of a jet transport aircraft is to:

Recirculate the air Signup and view all the answers

Which statement is most correct regarding crew alert messages?

Warnings are color coded red, cautions and advisories are amber Signup and view all the answers

Which of the answers listed below best represents the display of active waypoints and active routes?

Active waypoints are displayed in magenta and tracks as solid magenta lines Signup and view all the answers

Which of the following combinations of flight director/autopilot modes are not selectable together?

HDG SEL and HDG HOLD Signup and view all the answers

In a gas turbine engine, how does thrust produced at engine design RPM vary?

An OAT increase will lead to a thrust decrease Signup and view all the answers

In a turboprop powered aircraft, the power lever is used to control:

Pitch and torque in all operating ranges Signup and view all the answers

The EPR of a gas turbine engine may be defined as:

The ratio between the engine inlet pressure and the exhaust duct pressure Signup and view all the answers

The EGT of a gas turbine engine may be defined as:

The temperature of the gas flow at the exit from the combustion chamber Signup and view all the answers

As a flight progresses and weight decreases as fuel is burnt in a transport category aircraft:

Optimum speed decreases, maximum altitude increases and buffet boundaries increase Signup and view all the answers

The freezing point of Jet-A1 fuel is closest to:

-40°C Signup and view all the answers

What is the purpose of the bogie wheel landing gear configuration compared to a single wheel on a main gear leg?

Reduced tire pressure and lower ACNs Signup and view all the answers

Which of the following statements is correct concerning the operation of the Ground Proximity Warning System?

A hard warning is not always preceded by a soft warning Signup and view all the answers

On a turboprop aircraft, the purpose of the safety coupling is to:

Disconnect the propeller from the gearbox in the event of excessive negative torque Signup and view all the answers

The measurement of temperature in a gas turbine engine is one of the most critical items of information the pilot needs for safe operation. Which statement correctly describes the usual application of various thermocouple probe types?

Rapid response probes are used primarily in turbojet and turbofan installations while stagnation type probes are used mainly in turboprop installations Signup and view all the answers

With differential spoilers fitted to an aircraft, a left bank will require:

The left spoiler to extend if both were retracted Signup and view all the answers

The auto-brake selector has eight positions: DISARM, OFF, 1, 2, 3, 4, MAX and RTO. Which statement regarding the retardation rates of various settings is true?

Manual braking is greater than both RTO & MAX Signup and view all the answers

While in cruise at a constant Flight Level at M0.82, an increase in ambient temperature will result in:

A higher TAS and a higher SFC Signup and view all the answers

What indicates that self-sustaining speed has been achieved during the start cycle of a gas turbine turbofan engine?

The turbine first starts to drive the compressor Signup and view all the answers

In the event of a failure of the active sources of 115 Volts AC in a transport category aircraft, which component of the electrical system supplies the AC power?

The Static Inverter Signup and view all the answers

As a turbofan powered aircraft climbs through the tropopause, thrust will:

Reduce at a greater rate compared to below the tropopause Signup and view all the answers

TCAS-2 TA ONLY mode is selected by the crew. Which statement is correct regarding advising of threat levels to the crew?

RA will not be displayed aurally nor visually Signup and view all the answers

An aircraft flies above its mach trim speed, the mach trim system will:

Deflect the leading edge of the horizontal stabilator downwards Signup and view all the answers

What is the difference between the de-ice system and the anti-ice system?

Anti-ice is selected on prior to entering an area of ice and de-ice after entering it Signup and view all the answers

In aircraft fitted with Series Type Yaw Dampers:

They are normally turned on during all phases of flight. The pilot rudder pedals will not move in response to yaw damper movements Signup and view all the answers

Regarding the gas flow in the combustion section of a gas turbine engine:

Pressure and temperature increase Signup and view all the answers

The effect of a center of gravity (CG) position on the cruise speed of an aircraft for a given thrust setting and weight in level flight is:

A rearward CG (within limits) results in a higher cruise speed Signup and view all the answers

In an aircraft equipped with a Flight Management Computer (FMC), a holding pattern programmed into the FMC LNAV active route will command the holding pattern track taking account of:

The actual wind Signup and view all the answers

Gas turbine engine mass airflow is governed primarily by:

The RPM, the number of compressor stages, and the turbine inlet temperature Signup and view all the answers

The correct procedure to follow in the event of a hot start to prevent torching in a gas turbine engine is to:

Motor the engine with the fuel supply cut off Signup and view all the answers

An advantage of NICAD batteries in an aircraft installation compared to lead acid batteries is:

Faster recharge cycle Signup and view all the answers

Regarding the forces acting on an aircraft in a steady climb:

Lift is greater than weight and thrust is greater than drag Signup and view all the answers

The component of the autopilot system which safeguards against a servomotor runaway is:

The torque limiter Signup and view all the answers

An aircraft landing gear tire replacement should be considered essential with:

A deep cut in the tread Signup and view all the answers

The fuel boost pumps in a jet transport category aircraft fuel system are located:

In the fuel tanks Signup and view all the answers

The function of the follow-up linkage in the nose wheel landing gear system of a jet transport category aircraft is:

To stop tire scuffing Signup and view all the answers

The nose-wheel centering system of large jet aircraft operates to straighten the nose wheel:

Prior to gear retraction Signup and view all the answers

Study Notes

Gas Turbine Engine and Thermal Considerations

The highest temperature in a gas turbine engine is located in the primary part of the combustion chamber.
The HOT battery bus power can originate from the aircraft battery or any connected battery as well as ground service supply.

Anti-skid Systems

Primary anti-skid system elements include tire lockup, landing, and takeoff protection, but pneumatic reserve braking is not included.

Turbojet vs. Turbofan Characteristics

A turbo-fan’s high-pressure turbine is smaller compared to a turbojet of equal thrust due to increased mass airflow.
During climbs in turbo jets, fan speed (N1) is maintained.

Shockwaves and Airflow

Ahead of a normal shockwave, airflow is supersonic and sub-sonic behind it, causing changes in airflow direction.

Vortex Generators and Fuel Properties

Vortex generators on horizontal stabilizers reduce turbulent flow and maintain elevator authority.
Dissolved water in Avtur fuel decreases specific gravity and causes corrosion.

Tire and Aircraft Systems

Tires should be replaced when there are bulges, cuts to tread limits, or flat spots.
Air conditioning load can be alleviated by increasing the amount of air bled by the anti-ice system.

Gear Behaviors and Aerodynamics

Body gear is generally non-steerable and turns opposite to nose gear to mitigate tire scuffing.
Spiral instability is exacerbated when directional stability surpasses lateral stability.

Climb Performance and VMC

Maintaining constant calibrated airspeed (CAS) during climbs causes both Mach number and true airspeed (TAS) to increase.
VMCG speed can be reduced by decreasing takeoff thrust settings or repositioning the center of gravity.

Engine Failure Dynamics

In the event of losing an engine while banking toward the operational engine, less rudder deflection is necessary, with slight skid ball displacement to the live engine side.
For aircraft with engines mounted beneath the wings and one tail-mounted engine, failure of the left engine requires right rudder trim.

Aerodynamic Features

The primary advantage of a supercritical wing is to decrease the critical drag rise number and enhance lift at given angles.
Slots and leading edge devices primarily increase lift, particularly at high angles of attack.

Weather and Humidity in Aircraft

Ideal cabin humidity for comfort is 60%, while cruising altitude humidity can be about 0%.
The preferred temperature range for humans in an aircraft cabin is 18-24°C.

Autopilot and Electrical Systems

Autopilot systems can operate in a "Fail Passive" mode, whereby one failure isolates it from the others, maintaining function.
The Transformer Rectifier Unit (TRU) converts AC power to DC power, adjusting voltage levels as needed.

Hydraulic and Pneumatic Systems

Use check valves in hydraulic systems to maintain correct flow directions.
Pneumatic systems typically weigh less than hydraulics, although they carry risks like potential leaks.

Shockwave Properties

At increased speeds, airflow characteristics behind a normal shockwave show temperature and pressure rise, while velocity and Mach number decline.

Overall Aerodynamics and Stability

High-speed stall and low-speed stall manifest the same at an aircraft's certificated ceiling, suggesting altitude affects indicated airspeed.
Increased apparent gross weight reduces the speed margin between initial buffet speeds, indicating less stall prevention buffer under higher loads.### Aircraft Systems Regulations
Cabin altitude must not exceed aircraft altitude.
Cabin pressure must remain above outside ambient pressure at all times.
Maximum positive pressure differential must be limited.
Ambient pressure must not exceed cabin pressure during landing.

Shuttle Valve in Hydraulic Systems

Allows alternate system pressure to pressurize lines if the normal system fails.
Vents excess pressure back to the reservoir during low demand.
Permits two hydraulic systems to supply pressure simultaneously.
Ensures proper sequence of components for landing gear operation.

Air Conditioning System Components

Coldest air in the air cycle machine is found in the expansion turbine.
Both primary and secondary heat exchangers play roles in temperature regulation.

Hydraulic System Surge Suppression

Accumulator acts as a surge suppressor in hydraulic systems.

Gas Turbine Engine Temperature

Highest temperature occurs in the primary zone of the combustion chamber.

Turbojet vs. Turbofan Performance

In a pure turbojet, rear (LP) turbine wheels are smaller and rotate faster compared to a high bypass turbofan of the same thrust output.

VMCA Factors

High density altitude, dihedral, and skid-induced blanketing decrease VMCA.
Dihedral, banking towards the failed engine, and a large tail fin increase VMCA.

Air Conditioning Load Reduction

Engine air bleed load in air cycle systems can be reduced by recirculating air.

Crew Alert Messages

Warnings are color-coded red; cautions and advisories are amber.
Aural warnings are associated with warnings, cautions, and advisories.

Active Waypoint and Route Display

Active waypoints are shown in magenta; tracks display as solid magenta lines.

Flight Director/Autopilot Compatibility

Certain mode combinations such as HDG SEL and HDG HOLD are not selectable together.

Gas Turbine Thrust vs. OAT

An increase in Outside Air Temperature (OAT) leads to a decrease in thrust.

Turboprop Power Control

The power lever controls pitch and torque in all operating ranges.

EPR Definition

Engine Pressure Ratio (EPR) is the ratio between engine inlet pressure and exhaust duct pressure.

EGT Definition

Exhaust Gas Temperature (EGT) is measured at the exit of the turbine.

Weight Impact on Flight

As fuel is consumed, maximum altitude decreases, while optimum speed decreases.

Jet-A1 Fuel Characteristics

The freezing point of Jet-A1 fuel is approximately -40°C.

Bogie Wheel Landing Gear Advantages

Provides reduced tire pressure and lower Aircraft Classification Numbers (ACNs).

Ground Proximity Warning System

A hard warning may not always follow a soft warning.

Turboprop Safety Coupling

Disconnects the propeller from the gearbox in cases of excessive negative torque.

Temperature Measurement in Gas Turbine Engines

Rapid response probes are mainly used in turbojet/turbofan engines; stagnation probes are for turboprops.

Aircraft Control Surface Operations

With differential spoilers, a left bank requires the left spoiler to extend if both are retracted.

Auto-Brake Selector Function

RTO mode has greater retardation rates than MAX.

Effects of Ambient Temperature on Cruise

An increase in ambient temperature while cruising at a constant Flight Level raises True Airspeed (TAS).

Self-Sustaining Speed in Engine Start

Achieved when the starter disengages during the start cycle.

AC Power Source in Failures

A Static Inverter supplies AC power in case of 115V AC source failure.

Thrust Changes at Tropopause

Thrust reduces at a greater rate above the tropopause compared to below.

TCAS-2 TA ONLY Mode

Resolution Advisory (RA) will not be displayed aurally or visually.

Mach Trim System Effects

Above the mach trim speed, the system deflects the trim tab downwards.

De-ice vs. Anti-ice Systems

Anti-ice is active prior to entering ice areas, de-ice is applied after ice formation.

Series Type Yaw Dampers

They operate continuously, independent of pilot inputs during flight.

Combustion Section Gas Flow

Pressure increases while temperature also rises in the gas turbine engine.

CoG Position Impact

A rearward Center of Gravity (CoG) leads to higher cruise speeds, within operational limits.

FMC and Holding Patterns

The FMC routes will consider actual wind conditions during holding patterns.

Air Flow in Gas Turbine Engines

Mass airflow is primarily influenced by RPM and compressor stages.

Hot Start Mitigation

In case of a hot start, the correct action is to motor the engine with fuel cut off.

NICAD vs. Lead Acid Batteries

NICAD batteries don't emit dangerous gases and have a faster recharge cycle.

Forces During Steady Climb

During a steady climb, lift equals weight and thrust equals drag.

Autopilot System Safety Features

The torque limiter safeguards against servomotor runaway.

Tyre Replacement Indicators

Essential replacement occurs with visible bulges or deep cuts in aircraft tires.

Fuel System Pump Location

Fuel boost pumps are located within the fuel tanks of jet transport aircraft.

Nose Wheel Landing Gear Functions

Follow-up linkage prevents nose wheel shimmy and maintains correct steering angles.

Nose-Wheel Centering Operations

Works to straighten the nose wheel prior to gear retraction.### Aircraft Systems and Operations
Inboard ailerons on aircraft with both outboard and inboard ailerons operate at all times.
During TCAS operations in TA-only mode, RAs are shown as TAs.
Airflow behind a vertical shockwave experiences a decrease in total pressure (energy).
A benefit of Split Bus electrical systems is reduced frequency-matching requirements.
Engine bleed air is utilized for anti-icing, air conditioning, and pressurization.

Performance Factors

In-flight engine bleed air for wing anti-icing is used continuously during known icing conditions.
The radio altimeter display on the EADI is blank when above 2500 ft.
When climbing at a constant Mach number, true airspeed (TAS) decreases in the troposphere and remains constant in the isothermal layer.
The EFIS MAP reference heading can be either true or magnetic depending on pilot selection or latitude.

Instrumentation and Backup

A HDG flag on the Captain's HSI indicates a likely HDG flag on the First Officer’s HSI.
Specific Air Range (SAR) reflects the ratio of distance travelled per tonne of fuel used.
Engine Pressure Ratio (EPR) is the ratio between total jet pipe pressure and total engine inlet pressure.
Exhaust Gas Temperature (EGT) is the temperature of gas flow exiting the combustion chamber.
Windshield rain repellent fluid should not be used on a dry windshield to prevent smearing.

Safety and Engine Response

A successful light-off in a gas turbine engine is indicated by increasing EGT.
Kerosene has advantages over wide cut fuel due to its higher flash point and lower volatility.
In a pressurized climb, the cabin altitude increases with continued climb beyond maximum differential pressure.
Reverse thrust is most beneficial at high forward speed during landing rolls.

Autopilot and Flight Management

Autopilot hardover signifies full servomotor deflection.
An autopilot system 'mimicking' control wheel inputs operates in parallel.
Monitoring autopilot status using land indications indicates redundancy; land 2 allows for automatic landing despite single faults.
If LNAV is engaged but no descent point is programmed, the FMC directs the aircraft to maintain its present track.

Flight Operations Conditions

The approach speed in gusty conditions can increase to VREF + 20 kt for wind gradients.
Hydraulic fluid pumps are lubricated and cooled by hydraulic fluid itself.
The antiskid brake system allows maximum braking without traction loss, with rapid oscillation indicating possible system issues.
Multi-engined aircraft typically fly asymmetric with a bank away from the dead engine.

Aircraft Configuration and Performance

Differential spoilers interact with control during banking; left bank results in the left spoiler extending if both were retracted.
Charging lead acid batteries in aircraft is typically done using constant voltage method.
Inertial Reference Systems can derive current true heading independently by using gyro-stabilized compasses.
The command speed bug on the airspeed indicator is referenced to V2 when configured for takeoff.

Performance Analysis and Control

Poor oscillatory stability at higher altitudes is due to reduced aerodynamic authority from lower air density.
Effective management of thrust after V1 during engine failure relies on proper pilot responses.
A bogie wheel landing gear configuration provides better pressure distribution compared to a single wheel.

Electrical Systems and Failures

Aircraft electrical generators operate in series to enhance reliability.
A large AC generator cannot restart in-flight if residual voltage drops to zero without available battery power.
Integrated Drive Generators (IDG) disconnect from engines automatically in case of an internal failure, affecting power frequency.

Efficiency Considerations

Combustion in gas turbines primarily raises gas temperature, essential for efficient engine performance.
Most effective combustion chamber designs are the can-annular design for efficiency and cost-effectiveness.

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Prepare for your ATPL Aerodynamics & Systems Exam 1 with this practice quiz. This set of questions covers essential topics from the syllabus and will help you assess your understanding and readiness for the final assessment. Use this as a valuable resource to enhance your knowledge and confidence.