Airplane Systems Flashcards
What are elevators?
Attached to horizontal stabilizer
Used to control pitch about the lateral axis
What are ailerons?
Moveable surfaces attached to trailing edge of each wing
Used to roll/bank the airplane about the longitudinal axis
What is the rudder?
Attached to the vertical stabilizer
Used to yaw the airplane about the vertical axis
Explain what moveable trim devices are, and what they do.
Small tabs attached to the trailing edge of control surfaces
Used to relieve control pressures
How do elevator trim tabs move?
Trimming nose-up causes the trim tab to move up, forcing the tail downward and the nose up
Trimming nose-down causes the trim tab to move down, forcing the tail upward and the nose down
What are flaps, and what is their function?
Moveable panels on the inboard trailing edges of the wings
Increase both lift and drag
Permit steeper descents at slower airspeeds
Can be used to shorten takeoff distances
Define plain flap.
Simplest design, hinged panel
Produces significant increase in coefficient of lift, as well as drag
CP moves aft, causing nose-down pitching moment
Define split flap.
Deflected from lower surface of airfoil
Produces slight increase in lift, but greater increase in drag (because of turbulent air behind wing)
Define slotted flap.
Increases lift coefficient significantly more than plain or split flaps
Air passing through duct created when flap is deployed delays airflow separation
Define Fowler flap.
Slotted flap that changes the camber of the wing, and increases wing area
First extension greatly increases lift
Further extensions greatly increase drag
What are slots and slats?
Direct high energy air from under the wing to over the wing, accelerating airflow and increasing lift
Slats act as moveable slots
What are spoilers?
Located on the upper surface of the wing
Used as “speed brakes” to slow the airplane down
Which instruments operate from the pitot-static system?
Airspeed indicator
Altimeter
Vertical speed indicator
What is an alternate static air system?
Draws static pressure from inside the cabin
Used if the external static port becomes blocked
How does an altimeter work?
Aneroid wafers expand/contract with changes in static pressure
Drives shaft/gear linkage
What errors in the altimeter are caused by temperature/pressure changes?
High temperature-altimeter indicates lower than actual
Low temperature-altimeter indicates higher than actual
High pressure-altimeter indicates lower than actual
Low pressure-altimeter indicates higher than actual
What is indicated altitude?
Read from altimeter set to current altimeter setting
What is pressure altitude?
Read from altimeter when set to 29.92
What is true altitude?
Actual vertical distance above sea level
What is density altitude?
Pressure altitude corrected for non-standard temperature
Used to calculate takeoff, climb, and landing performance
What is absolute altitude?
Vertical distance above surface/terrain
How does an airspeed indicator work?
Measures difference between impact pressure (pitot) and static pressure
What is a limitation of the airspeed indicator?
Location of pitot tube, needs uninterrupted airflow
What is position error, with respect to the airspeed indicator?
Caused by erroneous sensing of static port(s) due to slipstream
What is density error, with respect to the airspeed indicator?
ASI cannot detect changes in altitude or temperature
What is compressibility error, with respect to the airspeed indicator?
Caused by packing of air in the pitot tube at high speeds
What does the lower limit of the white arc on the ASI indicate?
Vso-stalling speed in landing configuration
What does the upper limit of the white arc on the ASI indicate?
Vfe-maximum flap extension speed
What does the green arc on the ASI indicate?
Normal operating range
What does the lower limit of the green arc on the ASI indicate?
Vs1-clean (or specified configuration) stall speed
What does the upper limit of the green arc on the ASI indicate?
Vno-maximum structural cruise speed
What does the yellow arc on the ASI indicate?
Caution range-operations in smooth air only
What does the red line on the ASI indicate?
Vne-never exceed speed
What are some V-speeds that are not indicated on the ASI?
Va-design maneuvering speed Vlo-landing gear operating speed Vle-landing gear extended speed Vx-best angle of climb speed Vy-best rate of climb speed
How does a vertical speed indicator work?
Calibrated leak inside the instrument case that registers rate of pressure change
What is the main limitation of the vertical speed indicator?
Not accurate until aircraft is stabilized
Which flight instruments contain gyroscopes?
Attitude indicator
Heading indicator/directional gyro
Turn coordinator
What are the two fundamental properties of a gyroscope?
Rigidity in space
Precession
How are the gyroscopes powered in most modern training airplanes?
AI and DG powered by vacuum system
TC electrically powered
How does the vacuum system work?
Air is drawn in through a filter by an engine-driven pump, and directed to the gyroscopic instruments
What are some limitations of the attitude indicator?
Pitch limits of 60-70
Bank limits of 100-110
Exceeding limits will cause instrument to “tumble”
What is the main error of the heading indicator/directional gyro?
Will tend to drift from heading to which it was set
Needs to be aligned with compass periodically
What information does a turn coordinator show?
Approximate rate of turn
Coordination of turn
What is a skidding turn?
Too much rate of turn for amount of bank
Ball is to the outside of the turn
What is a slipping turn?
Not enough rate of turn for the amount of bank
Ball is to the inside of the turn
How does a magnetic compass work?
Magnetized needle, attached to card, floats in sealed bowl of white kerosene
Needle aligns itself parallel to the lines of earth’s magnetic force
What is oscillation error, with respect to a magnetic compass?
Erratic movement caused by turbulence/rough control
What is deviation error, with respect to the magnetic compass?
Caused by electrical/magnetic disturbances within the aircraft
What is variation error, with respect to the magnetic compass?
Angular difference between true and magnetic north
What is acceleration error, with respect to the magnetic compass?
On east or west headings, acceleration shows a turn to the north, and deceleration shows a turn to the south
ANDS-Accelerate North, Decelerate South
What is the northerly turning error, with respect to the magnetic compass?
Compass leads in the south half of a turn, and lags in the north half of a turn
UNOS-Undershoot North, Overshoot South
What components of a typical GA aircraft would be considered parts of the hydraulic system?
Retractable landing gear
Air/oil struts
Hydraulic brakes
What are the basic characteristics of the engine in a typical training aircraft?
Normally aspirated Direct drive Air cooled Horizontally opposed Carburetor/fuel injection
Describe the four strokes of a typical, piston-driven engine.
Intake-downward, fuel mixture is drawn into the cylinder
Compression-upward, mixture is compressed
Power-downward, mixture is ignited, forcing piston down/creating power
Exhaust-upward, burned gases pushed out through the exhaust valve
What does a carburetor do?
Vaporizes fuel and mixes it with air to form a combustible mixture
How does carburetor heat work?
Unfiltered air from a shroud around the exhaust is redirected to the carburetor
What is fuel injection?
Fuel/air mixture is injected directly into cylinders, or into intake manifold ahead of intake valves
What are some advantages of fuel injection?
Reduction in evaporative icing Better fuel flow Faster throttle response Precise control of mixture Better fuel distribution Easier cold weather starts
What are some disadvantages of fuel injection?
Difficulty starting a hot engine/vapor lock
What is an alternate air induction system?
Brings airflow to engine if primary induction inlets become blocked by ice
What does the throttle do?
Allows pilot to control amount of fuel/air mixture going to cylinders
What does the mixture control do?
Regulates air/fuel ratio
Allows pilot to reduce amount of fuel to compensate for reduced air density
What does a turbocharger do?
Compresses air, allowing aircraft to maintain performance at higher altitudes
Turbine, driven by exhaust gases, drives compressor
How are cowl flaps used?
Open during startup, taxi, takeoff, and climb
Adjusted during cruise to maintain optimal CHT
Closed during descent, approach, and landing
What are the two types of fixed-pitch propellers?
Climb-lower pitch, less drag, higher rpm, decreased cruise performance
Cruise-higher pitch, more drag, lower, rpm, reduced climb performance
How does a constant speed (variable pitch) propeller work?
Engine rpm is governed by propeller blade angle
Propeller control sets limit on propeller governor which, in turn, maintains engine speed
Describe the components of the fuel system in a typical, low-wing, training aircraft.
Wing-mounted tanks Tank selector valve Inline, electrically driven fuel pump Inline fuel strainer/filter Engine driven, mechanical fuel pump
When is the electrical fuel pump typically used?
During startup
When changing selected fuel tank
During takeoff and climb
During approach and landing
What is the purpose of fuel tank vents?
Allow air to enter tanks to replace the fuel that is used
What are the colors of the various grades of fuel?
80-red
100-green
100LL-blue
Jet A-colorless/straw
What does the manual primer do?
Injects fuel directly into one or more cylinders, to assist in engine start
What equipment is powered by the aircraft electrical system?
Radios Turn coordinator Fuel gauges Pitot heat Interior/exterior lights Oil temperature, CHT, EGT gauges Flaps (if equipped) Landing gear pump (if equipped)
What are the advantages of dual ignition systems in aircraft engines?
Redundancy
Efficiency
What are the 3 most common types of oxygen systems?
Continuous flow
Diluter-demand
Pressure-demand
What is a pressurized aircraft?
Sealed fuselage
Pressurized air pumped in
Cabin pressure altitude of 8000’ typically maintained
Allows aircraft to fly at higher altitudes
How is cabin pressure monitored in a pressurized aircraft?
Cabin differential pressure gauge-difference between cabin/ambient pressures
Cabin altimeter-used to verify system performance
What is the difference between a de-ice and an anti-ice system?
De-ice-eliminates ice already formed
Anti-ice-prevents ice from forming
What is AHRS?
Attitude and heading reference system
Sensors provide heading, attitude, and yaw information
Replaces vacuum-driven gyroscopic system
What is an ADC?
Air data computer
Receives/processes pitot-static information
What is a PFD?
Primary flight display
Replaces traditional “6-pack” flight instruments
What is an MFD?
Multi-function display
Can be used to display engine instruments, GPS, terrain awareness, etc.
What is an FD?
Flight director
Analyzes navigation signals and aircraft parameters
Provides steering instructions on the PFD
What is an FMS?
Flight management system
Database for programming routes, approaches, procedures, calculating time, distance, range, and fuel burn
Describe the position lights on an aircraft?
Red light on left wingtip
Green light on right wingtip
White light either on vertical stabilizer, or rear of both wingtips
