jeppesen airframe orals Flashcards
What is the function of a vortex generator?
It is designed to delay or prevent separation of the boundary layer.
What are the three axes of an airplane?
Longitudinal, lateral, and vertical.
What are the three primary flight CONTROLS of an aircraft?
The ailerons, elevator, and rudder.
Name several SECONDARY flight controls and describe their general purpose? (Tabs) (5)
trim tabs
balance tabs
anti-servo
servo tabs
spring tabs.
Their function is to assist the pilot in moving the controls and to trim the aircraft to fly hands-off.
Name several types of AUXILIARY flight controls and describe their general purpose? (Flaps) (4)
high-lift devices used during low-speed flight
-flaps
-slats
-slots
-speed brakes
What is a servo trim tab?
auxiliary control, controlled by a cockpit control movement and creates aerodynamic forces to assist in moving a control surface.
What is a spring tab?(high speed)
It is an auxiliary control designed to aid the movement of a primary control at high speeds when control forces become too high.
What is a balance trim tab?
positioned by a control rod connected to the fixed surface on the same side as the horn on the tab.
What are four most common types of high LIFT devices? (Rhyme)
Leading flaps
Trailing flaps
slats
slots.
Describe some of the tools used to check control surface TRAVEL?
-universal propeller protractor
-special control surface protractor
Name three MECHANICAL methods by which flight CONTROL systems may be actuated.
-Cables
-Push-pull rods
-torque tubes.
What is a fairlead?
It is a device to prevent a cable from rubbing on the aircraft structure.
What are the most likely places for a control cable to wear or break?
Where the cables pass over pulleys or through fairleads.
What information is required before a cable rigging chart can be used?(metal cable)
The ambient temperature and the cable size.
What is the function of a cable tension regulator?
It automatically adjusts the cable tension to compensate for expansion and contraction in the aircraft structure.
Describe the function of a rotorcraft COLLECTIVE pitch control.
The collective control causes each rotor blade to change its pitch angle by the same amount, thus increasing or decreasing the lift produced by the rotor.
Describe the function of a rotorcraft CYCLIC pitch control.
The cyclic control tilts the main rotor disc by changing the pitch angle of each rotor blade during its cycle of rotation, which causes the helicopter to move in the direction the rotor tilts.
What mechanism is most commonly used to compensate for the torque produced by the main rotor of a helicopter?
The tail (or anti-torque) rotor.
How is the amount of thrust produced by the tail rotor controlled?
By moving the foot pedals.
Why should control surfaces be locked when an aircraft is parked?
To prevent damage from the wind.
What is the major type of damage to aluminum structures that is caused by exposure to the weather?
Corrosion.
Name several methods for FORMING sheet metal.(ing)(5)
-Bending or folding
-stretching
-shrinking
-bumping
-crimping.
What are the dimensions of a properly formed rivet head?
The head should be 1 1/2 times the shank diameter in width and 1/2 the shank diameter in height.
Describe the markings found on the heads of A, B, D, AD, and DD rivets.
A rivets are plain
B rivets have a cross
D rivets have a raised dot
AD rivets have a dimple
DD rivets have a double dash.
What happens to the stem of a self-plugging (friction lock) rivet when the rivet is installed?
The stem is pulled until it snaps off and the remaining projecting part is trimmed flush with the head.
Name at least three types of self-plugging mechanical lock rivets.
CherryMAX®, CherryLOCK®, OLYMPIC-LOK®, and HuckLok® rivets.
What is the difference between the tools required to pull a CherryLOCK rivet and a CherryMAX rivet?
CherryLOCK rivets require a tool for each different size and head shape, while one pulling tool will set any size CherryMAX rivet.
Which of the five stresses is the most common cause of rivet failure?
Shear.
If a 2024 rivet must be replaced with a 2117 rivet, how do you determine the size to be used?
For 5/32” or smaller diameter, use the next larger size 2117 rivet, assuming that the edge distance and spacing meet the minimum requirements.
Describe the process for determining the total length of a solid rivet for a particular installation.
Add the grip length (thickness of the materials being joined) plus 1 1/2 times the rivet diameter.
What minimum edge distance and spacing should be used for a single row of protruding head rivets?
Not less than two rivet diameters from the edge and not less than three rivet diameters apart.
How can a mechanic determine whether the countersink for a flush rivet should be dimpled or drilled?
By the thickness of the top sheet; thin sheets are dimpled while thick sheets may be countersunk.
What action is taken to prevent cracks from forming while dimpling magnesium or some hard sheet metals?
Hot dimpling equipment is used to preheat and soften the metal before the dimple is formed.
What type of damage can occur when using a rivet set that does not properly fit the rivet?
If the radius of the set is too small, the rivet head may be damaged, whereas a set with an over-sized radius may cause damage to the sheet metal.
Why is it important to use the proper size and weight bucking bar when performing sheet metal riveting?
If a bucking bar is too large or heavy it may be difficult to control and may cause damage to the surrounding structure, whereas a bucking bar that is too light will not properly upset the rivet before work hardening occurs.
What procedures should be followed to properly remove a solid-shank rivet?
Center punch the rivet and then drill just to the base of the rivet head with the same size or one size smaller drill. Once drilled, use a pin punch to tip off the rivet head and drive the remaining shank out of the hole while supporting the surrounding metal.
What are the two special calculations that must be made when bending sheet metal?
Bend allowance and setback.
What factors must be considered in order to determine setback?
The thickness of the metal and the bend radius.
What is done to a corner where two bends intersect to prevent cracking?
Relief holes are drilled in the corner.
What are the two reasons for installing a lightening hole in a sheet metal wing rib?
Lightening holes reduce the weight and increase stiffness.
Describe a joggle and explain its function.
A joggle is an offset formed at an intersection of two or more sheets of metal to allow the multiple sheets to be stacked flat against each other.
When repairing an all-metal aircraft, how do you determine what metals should be used?
Always use metal of the same type and thickness as the original structure.
What are the three forms of wood commonly used in aircraft construction?
Solid
laminated
plywood.
What type of wood should be used when splicing or reinforcing plywood webs?
The same type of plywood as originally used.
Name at least four different types of defects found in wood.(8)
-Knots
-checks
-splits
-pitch pockets
-cross grain
-curly grain
-decay
-dry rot
Can a section of wood containing a hard knot be used?
Yes, within specified limits.
What type of glue may have been used in older wooden aircraft construction that requires careful inspection to detect deterioration?(fat ginger lol)
Casein glue.
What are the three types of glues used in modern aircraft construction and repair?(resourceful)
-Resorcinol glue
-Phenol-formaldehyde glue
-epoxy resin glue
Is compression wood acceptable for structural repairs?
No.
Why should the various pieces of wood being joined be kept in the same room for at least 24 hours prior to joining?
To allow the moisture content to equalize, thereby minimizing dimensional changes in the wood.
Why is it important to consider the open-assembly time when gluing wooden structures?
If the maximum open-assembly time is exceeded, the joint may fail since the glue may begin setting up before the joint is assembled.
Why is it important to apply the proper clamping pressure to a glue joint?
forces air out of the joint
brings surfaces together evenly
strength of the glue line.
Describe some of the methods used to apply pressure to glue joints.
Clamps
nailing strips
power presses
brads
nails
small screws.
What minimum curing temperature should be observed when joining wood with various adhesives?
70 degrees Fahrenheit or as specified by the glue manufacturer.
When inspecting wood structures, why might it be important to consider stains and discolored areas?
Stains and discoloration usually accompany decay and/or rot.
Describe the acceptable methods used to repair elongated bolt holes found in a wooden wing spar.
Remove the section containing the elongated hole(s) and splice in a new section or replace the entire spar.
What type of joint is used to splice a solid or rectangular wood spar? (Dad’s favorite movie)
A scarf joint.
In what areas are splices to a wood spar prohibited?(4)
Under attachment fitting for wing root landing gear
engine-mount lift
inter-plane strut
What is the maximum number of splices allowed for any single spar?
Two.
Describe the characteristics of a scarf joint. (Yk what else is massive)
The pieces to be joined are tapered or beveled on a slope of 1 to 10 or 1 to 12.
Why must the beveled cut be accurate on both pieces of wood being repaired with a scarfed joint?
The two pieces must match exactly to ensure a tight glue joint.
What are the two primary uses for plywood in aircraft construction?
Gusset (or reinforcing) plates and aircraft skin.
Provide examples of at least THREE types of plywood skin repairs.(top, butt ___, dad movie)(PATCHES)
surface patches
plug patches
scarfed patches.
What type of patch should be used to repair small holes in thin plywood skin if the skin is less than 1/10th inch thick? (Funky Spray)
A splayed patch may be used if the hole can be cleared out to a diameter of less than 15 thicknesses of the skin.
What should be done to prevent a plywood patch and the pressure plate from sticking together if glue is extruded from the joint?
wax paper or vinyl plastic between the patch and the pressure plate.
Why are lightweight steel bushings sometimes used in wooden structures?
Bushings prevent the wood from being crushed when bolts are tightened.
What is the purpose of large surface area washers when used on wooden structures?
Large washers provide additional bearing area for hardware to help preclude damage to the wood when the hardware is tightened.
Name several facings and core materials used in bonded honeycomb structures intended for special applications.(7)(minecraft)(MWGC)
Stainless steel
titanium
magnesium
plywood
glass
nylon
Cotton cloth.
Describe the construction of a bonded honeycomb structure.
-laminated structure
-has a solid facing bonded to either side of a core
-open six-sided cells.
What must be done with a damaged area in a bonded honeycomb structure prior to beginning repairs?
Inspection prior to removal of damaged area
A drill bit used for drilling composites should operate at approximately what speed?
Pneumatic, 20k RPM
What are the most common causes for delamination of a composite structure?
Sonic vibration
internal moisture
leakage
manufacturing error
What type of defect in, or damage to, a bonded honeycomb structure can be repaired using the potted repair method?
Filling a hole.
Name some of the factors that cause crazing in transparent plastic windows and windshields? (WINDOWS)
Exposure to ultraviolet light, stress, solvents, and improper handling.
How should a hole be drilled in Plexiglas to avoid damage to the hole when the drill breaks through to the underside?
Back up the plastic with a piece of wood and feed the drill slowly.
Name the three principle types of welding.
Gas, electric arc, resistance welding.
What are some advantages of gas shielded arc welding?
The weld is stronger, more ductile, and more corrosion resistant.
Which method of welding is less likely to cause buckling or warping of thin metal sheets?
Electric arc (or TIG) welding.
What is the purpose of shielding an arc weld with an inert gas?
prevents atmospheric oxygen and/or nitrogen from contaminating the weld.
What is a common method of controlling expansion when welding a joint?
Place tack welds along the length of the joint.
What is the effect of inadequate penetration on a weld?
The weld will be weak.
What is the purpose of the flux used with brazing and silver soldering?
The flux cleans the base metal by removing any oxide film.
What type of flame is used when torch brazing or silver soldering?
A neutral flame.
What must be done to a soldering iron tip to increase the amount of heat transferred from the tip to the work?
The tip must be clean of all contaminates and properly tinned.
What is the preferred method for welding aluminum/magnesium?
Tungsten Inert Gas (TIG) welding.
What precautions must be observed in order to weld titanium?
All traces of oxygen and nitrogen must be kept away from the weld area.
Describe one type of repair that could be made to a dented steel tube cluster joint.
A formed steel patch plate could be welded over the damaged area.
How can a soft flame be obtained without reducing the heat output of the torch?
Use a larger tip and adjust the gas pressure accordingly.
What factors on the gun determine the amount of heat delivered by a gas welding torch?
size torch tip, gas pressure.
When an oxyacetylene torch is extinguished, which valve is turned off first?
Turn off the acetylene gas valve first.
When a gas welding project is completed, what safety precautions should be accomplished?
All the valves are turned off and the gas pressures are relieved.
What should be done to a heat-treated aluminum part after welded repairs are completed?
The part must be re-heat treated.
Welding magnesium can create a serious safety hazard. What is the nature of this hazard?
Magnesium burns with a very hot flame that is very hard to extinguish.
What technique might be used to enable a tight-fitting inner sleeve to be inserted into a tubular repair?
inner tube chilled, outer tube heated slightly
Aircraft covering fabrics are made of materials from what two SOURCES?
Organic materials and synthetic materials.
How would you determine the strength requirements for fabric used to re-cover an aircraft?
The fabric must be of at least the quality and strength of the fabric used by the original manufacturer.
What two types of organic fibers are used for covering aircraft?
Cotton and linen.
What is meant by warp, weft, and bias?(directions)
-Warp along the length of the fabric, -weft is the direction across the fabric at right angles to the warp
-bias is a direction at a 45 degree angle to the both
What is the purpose of the selvage edge on a roll of fabric?
It prevents the fabric from unraveling.
What identification marking is found on the selvage edge, and in which direction is the warp applied?
The FAA-PMA stamp is found on the selvage edge and the warp is applied parallel to the line of flight.
How are the fabric type and strength requirements determined for fabric-covered aircraft?
The original manufacturer determines the fabric type, and the strength requirements are a function of the never-exceed speed and wing loading.
What types of synthetic fibers are used for covering aircraft?
Fiberglass and heat-shrinkable polyester fibers.
Which of the several types of fabric is unaffected by moisture and mildew?
Fiberglass.
What is the function or purpose of reinforcing tape?
Reinforcing tape is used between the fabric and the rib stitching to prevent the lacing cord from cutting through the fabric.
Where would you use surface tape?(fabric)
Over rib stitching and sewed seams, over lapped edges, around corners, and along leading and trailing edges.
How should the edges of drainage, inspection, and ventilation holes be reinforced? (Wallace and ____)
With plastic, aluminum, or brass grommets.
What are the principle methods used to test the condition of fabric?
-Punch testers (Maule)
-laboratory pull-testing.
Fabric is considered unairworthy when it has deteriorated to what percentage of its original strength?
Less than 70%.
How should a structure that will be covered with doped fabric be prepared following inspection and prior to covering? (T-pain)
Treat it with a protective coating of paint or varnish as appropriate.
What is the principal advantage of the envelope method for covering wings?
Almost all the seams are machine-sewed by the envelope supplier.
What is a tie-off knot?
A standard, modified seine knot used on all stitches except the starting stitch.
Name three common types of machine-sewed seams.
Plain overlap, folded-fell, and French-fell.
Where are anti-tear strips used?
Under wing rib stitching when the never-exceed speed is greater than 250 mph.
How would you determine the correct spacing for rib stitching if the original spacing was unknown?
Consult the chart in AC 43.13-1B.
Why is butyrate dope safer to use than nitrate dope?
It is much less flammable.
What are the two types of dope used for fabric finishes? (Not sources)
Cellulose Nitrate and Cellulose Acetate Butyrate.
What is the appearance of a blushing paint finish?
Chalky or cloudy.
What finishing defect is the result of a paint room temperature that is too warm?
Pinholes or blisters.
What causes dope to blush?
High humidity, moisture in the spray system, or application over a damp surface.
What factors cause spray paint sags and runs?
Inadequate surface preparation or paint sprayed on too thickly.
What components or parts of the airframe must be protected from damage when using paint stripper?(acetone)(acid like chemical)
Windshields and windows, plastics, composites, synthetic rubber, and fabrics.
What is the function of zinc-chromate or wash PRIMERS? think metal
Primers serve to inhibit corrosion and provide a good bond between the metal and the topcoats.
Name several common types of paint used on aircraft.(5)
-Zinc-chromate
-wash primers
-synthetic enamels
-acrylic lacquer
-polyurethane.
What is the proper thinner to use with zinc-chromate primer?
Toluene.
What health and safety precautions must be observed when using the toxic solvents and thinners that are part of modern finishing systems?
Respirators and/or masks must be worn when spraying finishes.
If spray painting dust causes a surface to appear dry and rough, what are the most likely causes?
Too much air pressure or the spray gun is too far from the surface being painted.
What causes ‘orange-peel’?
-Spray pressure too high
-use of a thinner that dries too fast
-cold temperatures
-damp draft over the surface.
What regulation governs the application of the registration numbers to aircraft registered in the United States?
FAR Part 45.
Other than appearance, what is another reason for touching up painted surfaces?
Reduction or elimination of general corrosion problems.
What references should be used to determine if a control surface must be checked and/or rebalanced after painting?
The manufacturer’s service manual.
What would be the effect if dope was used over paint or enamel?
The dope tends to dissolve these materials.
What are the three most commonly used methods of applying paint?
Dipping, brushing, and spraying.
What is the effect on paint finishes if too much drier is added to the paint?
The paint film will be brittle and tend to crack and peel.
What paint system(s) may be used with epoxy topcoats?
Any paint system in good condition.
What could cause an AC electric motor to run too fast?
Excessive applied voltage or shorted field windings.
What tool is used to check a motor or generator armature for shorts and opens under load conditions?
A Growler.
When using a Growler, what indication will occur when a short exists between an armature segment?
Meral blade will begin to vibrate and “chatter.”
How is the output voltage of an alternator controlled?
By varying the field current that excites the alternator.
What instruments are used to monitor electrical system loads
Ammeters and voltmeters.
How would you identify a specific wire in a wire bundle?
By the identification code marked on the wire.
What tool would you use to determine the size of an unmarked wire?
-A wire gauge.
What color are the navigation lights on the wingtips?
The left wingtip is red, the right is green.
Name several types of electrical devices that would be considered intermittent loads on an electrical system
Landing gear, cowl and wing flap motors, radio transmitters.
Why would it be necessary to analyze an electrical system before increasing the load on the system?
To determine that the generator capacity, wire size, and protective device capacity will not be exceeded.
What factors should be considered when determining the wire size for a particular application?
-The system voltage
-voltage drop
-current to be carried
-wire length whether
-continuous or intermittent
What is the relationship between the inside diameter of a conduit and the outside diameter of the wire bundle inside it?
The conduit must be 25% larger than the wire bundle.
What is the maximum number of terminal lugs that can be placed on a single terminal strip stud?
Four
Under what conditions must a switch be derated from its nominal rating?
When used with inductive circuits, circuits with high in-rush current, and with DC motors.
At what point do electric motors draw the MOST current?
When starting.
Circuit breakers are designed to open before what condition occurs?
Before the wire emits smoke.
At what point in a circuit should the protective device be located?
As close to the power source as possible.
What type of circuit breaker may not be used in an aircraft?
An automatic resetting type
What part of an aircraft is identified by a white navigation light?
The tail.
What could cause an AC electric motor to run too slowly(3)
-Lack of lubrication
-defective wiring
-Low applied voltage.
What should be done when making bonding or grounding connections between dissimilar materials?(corrosion)
Use a suitable washer so that any corrosion will occur on the washer.
Prior to making a continuity check, what must be done to an electrical circuit? (Troubleshooting)
The power must be turned off.
What materials form the bases of the three types of hydraulic fluids?
Vegetable, mineral, and phosphate-esters.
What colors determine mineral-based and phosphate-ester-based hydraulic fluids?
Mineral based fluids are red and phosphate-ester based fluids are light purple.
What are the results of exposing lacquers, oil-based paint, plastic resins, and vinyl compounds to phosphate-ester-based hydraulic fluid?
The materials will be damaged and/or softened, or the paint will peel.
Name several sources used to develop hydraulic pressure. (What will transfer the fluid)
Hand pumps, engine-driven pumps, and electrically driven pumps.
What would cause the bypass valve in a hydraulic filter to open and allow unfiltered fluid to circulate in the system?(open and full flow)
A clogged filter element.
Describe several methods of PRESSURIZATION (air) a hydraulic reservoir.(3)
-Engine bleed air
-system pressure acting on piston
-variable-displacement hydraulic pumps.
What feature prevents engine damage if an engine-driven hydraulic pump seizes or is OVERLOADED
A shear section in the pump driveshaft will break, disconnecting the pump from the engine.
Describe the purpose of a pressure relief valve.
Pressure relief valves limit the maximum pressure produced by the pump, thereby preventing failures of the system components.
Engine-driven pumps deliver the OUTPUT fluid flow in what two forms?
As a constant volume or a variable volume.
Describe the operation of a gear-type pump
Two meshed gears, driven by a power source, rotate in a housing. Inlet fluid is carried around the outside of the gears and delivered to the outlet side as the gears rotate.
Describe the purpose of a pressure regulator.
manage the output pump to maintain system pressure.allows pump to be unloaded so it turns without resistance.
What is the device that is used in some systems to supplement the pump output during periods of high demand?
An accumulator.
What are the three different types of accumulators?(did what is his cup)(2 body parts)
Piston, diaphragm, and bladder.
What safety precautions must be taken prior to disassembling an accumulator?
Release all of the air or preload.
When a hydraulic unit is replaced, what precautions should be taken to avoid contamination of the system?
All lines should be capped or plugged immediately after they are disconnected.
What types of components or systems are pneumatically operated in some aircraft?
Landing gear, brakes, flaps, and other mechanical actuators.
Name several sources of pneumatic power.
Storage bottles, engine bleed air, engine-driven compressors or vane-type pumps.
What happens to excess pressure in a pneumatic system?
A relief valve vents it overboard.
What is the function of a restrictor in a pneumatic system?
To control the rate of flow of the airflow.
What are the reasons for periodically purging a pneumatic system?
To remove moisture and contaminants.
What is the purpose of a torque link on an oleo strut
To keep the wheel in alignment and prevent the piston from coming out of the cylinder.
A landing gear shock strut should be inflated with what gas(es)?
Nitrogen or dry air.
What conditions should a mechanic look for during a regular inspection of the exposed piston section of a landing gear?
Cleanliness, evidence of damage, and proper extension.
What prevents air from leaking out between the two halves of a split wheel assembly?
An O-ring
Why are fusible plugs installed on some aircraft wheels?
To release the pressure generated by heat build-up before a tire blows.
What safety precaution must be taken when removing a wheel from an axle or when disassembling a wheel?
Verify that the tire is completely deflated before removing a wheel from an axle or before wheel disassembly.
What are the visible signs of excessive heating on a wheel bearing?
The bearing surfaces show discoloration.
How are the pilot’s nose wheel steering commands transmitted to the steering control unit of a large aircraft?
Steering signals may be transmitted mechanically, electrically, or hydraulically
How is the nose wheel steering mechanism usually actuated on a small aircraft?
By means of a mechanical linkage connected to the rudder pedals.
What is the name of the unit that prevents a nose wheel from vibrating or oscillating?
A shimmy damper
What are the most common sources of power used to extend and retract landing gear?
Hydraulic pressure and electric motors.
At what times should a gear retraction check be performed?
During annual or other inspections and following a hard landing.
What mechanism(s) ensure that a nose wheel is not turned as it retracts into its wheel well?
-Internal centering cams
-external track.
Name several types of brake actuating systems
Independent master cylinders, boosted brakes, and power-controlled brakes.
What is the function of an anti-skid system?
Anti-skid systems allow large aircraft to achieve maximum braking effectiveness without allowing wheels to skid or lock.
What is the purpose of a DEbooster?
To reduce hydraulic system high pressure to a lower value for more satisfactory brake action.
Describe two methods of bleeding brakes.
-pressure pot attached to bleeder valve, fluid forced back to master cylinder/reservoir
-master cylinder forcing fluid from reservoir to the brakes.
Before a brake system can be inspected for leaks, what action must be accomplished?
Pressure must be applied to the system.
What maintenance function has the greatest impact on tire service life?
Ensuring that the tires are properly inflated.
What effect(s) does under-inflation have on aircraft tires?
Internal heat damage possibly leading to premature tire failure, and more tread wear on the shoulders than in the center.
What unit in an anti-skid system generates the anti-skid warning signal?
The control unit.
How is a pilot alerted that an anti-skid system has automatically returned to a manual brake system?
By a warning light.
What is the significance of an anti-skid warning?
The system is off or has failed.
By what usual means does the stall warning system in a small aircraft alert the pilot of an impending stall?
An audible alert and/ or a warning light.
What devices are used to provide warnings for a retractable landing gear system?
A horn or other aural device, and a red warning light or lights.
How can a pilot determine that the landing gear is down and locked?
A green light or lights and/ or another type of visual indicator.
Name at least two conditions that would activate a takeoff configuration warning system in a jet transport aircraft.
-Incorrect leading/trailing edge flap position
-stabilizer position
-speed brake not stowed
-manufacturer may establish other conditions.
What landing gear positions must be indicated by regulations?
-Down and locked
-up and locked.
Under what conditions will a landing gear aural warning sound?
When the throttle is retarded and the landing gear is not down and locked.
How does a takeoff configuration warning differ from a landing gear warning?
Takeoff warnings- intermittent horns
landing gear- steady.
What is the function of a Mach airspeed warning system?
To alert the pilot that the never-exceed airspeed limit has been reached or exceeded.
What systems are commonly used to activate the LANDING GEAR warning systems?
The throttles (thrust levers) and the wing flaps.
Why do airplanes with bleed air anti-icing of the wing leading edge have an anti-ice overheat light(s)?
To indicate an over-temperature condition, usually as the result of a break in the bleed air ducts.
What warning system may be required when a nickel-cadmium battery is installed in an aircraft?
A battery temperature monitoring system.
At what time would a check of a landing gear warning system normally be made?
During a landing gear retraction test.
What is the purpose of an annunciator system?
To show, by means of a warning light, that some system parameter requires attention by the flight crew.
If an aircraft with retractable landing gear has only one green light to indicate the gear is down and locked, how will the switches be connected, in series or in parallel?
In series.
Where would you locate the procedures for checking and adjusting the landing gear switches?
In the aircraft manufacturer’s manual.
What is the usual means for alerting the crew of a jet transport that the cabin doors are not properly closed?
A warning light.
Why are transport category aircraft equipped with a master caution and WARNING SYSTEM?
To alert the crew that a malfunction has occurred and corrective action may be required.
A static check may be performed on a manifold pressure gauge by using what piece of information?
Current atmospheric pressure.
What aircraft instrument can be used to check a manifold pressure gauge for proper indication?
The sensitive altimeter.
Name several of the indication errors that may be found in altimeters.(4)(friction)
Scale errors
hysteresis
friction
installation.
What is the signal source in an ELECTRICAL resistance-type temperature indicating system?
A temperature bulb or sensing element.
What type of temperature sensing system is normally used to measure a turbine engine exhaust gas temperature?
A thermocouple-type system.
What operating parameter is indicated by a tachometer?(what does it read)
Engine RPM (i.e., crankshaft or turbine rotor speed).
What is the name of the effect that causes a gyro to respond to an applied force at a point 90 degrees further in the direction of rotation?(precum)
Gyroscopic precession
What are the three sources of power used to drive a gyroscopic turn indicator?
Air from a vacuum or pressure source, or an electric motor.
What are two items that should be considered during inspection of a magnetic compass?(4)
- The fluid must be clear.
- The housing must be full with no bubbles.
- The card must be legible and the lubber line intact.
- The compass should be properly calibrated.
In what way do magnetic fields generated by electrical equipment and steel parts in the airplane affect a magnetic compass?
Stray magnetic fields deflect the compass from correct alignment with the earth’s magnetic field.
Describe the basic operating concept of a synchro-type remote indicating system
A remote transmitter electrically signals a receiver inside the instrument.
What aircraft instruments are connected to the pitot-static system(3)
-The altimeter
-vertical speed indicator
-airspeed/Mach meter
Why should you avoid cleaning obstructions from the sensing holes in a pitot-static system with a tool?
The holes are aerodynamically critical.
After components in a pitot-static system have been replaced, what tests or inspections are required?
The static system leak test specified by FAR 91.411.
What quantity is accurately measured by a capacitance-type fuel quantity indicating system?
The mass of the fuel.
Who is authorized to apply the range markings to an instrument dial face?
The manufacturer or a certificated instrument repair station.
What is the purpose of a slippage mark on an instrument glass?
To indicate if the glass has moved, which could cause incorrect range markings on an instrument that has the range markings painted on the glass.
What references should be consulted to determine the proper range markings for aircraft instruments?
The aircraft maintenance manual, aircraft flight manual, Type Certificate Data Sheets or Aircraft Specifications.
What is the meaning of a yellow arc on an aircraft instrument?
A caution or limited flight operations range.
What is the reason for ‘swinging’ a compass and how is it accomplished?(adjusting)
To compensate for deviations, caused by magnetic fields in the aircraft, by adjusting the compensating magnets.
What are the basic components of a radio communication system?
microphone
transmitter
receiver
speaker or headphones.
What frequency range is used by most modern voice communications systems?
The VHF (Very High Frequency) band (118.0 to 136.975 MHz).
What does the term ‘ADF’ stand for? Navigation
Airborne Direction Finding (Finder).
What is the function of VOR equipment?
Navigation.
Name the components of a typical airborne VOR navigation system.
A receiver, antennas, frequency selector and a visual display indicator.
What does DME stand for? (Nav)
Distance Measuring Equipment.
At what interval must an ATC transponder system be certified?
Every 24 calendar months.
Why are two antennas usually required for an ILS system?
The localizer and glideslope signals are transmitted on different frequencies.
What information does the glideslope beam provide?
Vertical guidance to enable the aircraft to maintain the correct descent angle.
What is the power source for an ELT (Emergency Locator Transmitter)?
An internal battery.
Describe one method of monitoring the signal output during an ELT test.
Tune a communications receiver to 121.5 MHz.
How would you determine if the batteries in an ELT are due for recharge or replacement?
By looking for an expiration date for recharge or replacement on the battery and/or in the aircraft maintenance records.
At what time(s) is a test of an installed ELT permitted?
During the first 5 minutes after the hour and for no more than 3 sweeps.
Where on the aircraft would you expect to find a DME antenna?
Generally on the bottom of the fuselage in a location that isn’t blocked by the wing during turns.
Describe the shape and location of a transponder antenna.
Either a short blade or a short wire with a ball end located on the bottom of the fuselage.
Name the basic COMPONENTS of an autopilot system.
-Gyros
-servos
-controller
-computer
What are the sensing elements of an autopilot system? (What components)
Attitude, directional, and turning gyros
Altitude sensors
What is the function of the servos in an autopilot system?
The servos actuate the flight controls.
What is the purpose of a bonding jumper from a radio shock mount to the airframe?
To provide a low-impedance ground return.
Describe the procedure used to route coaxial cable from an antenna to a receiver.
-supported every 2 feet
-bends 10 times the diameter
-routed separately from other wires.
What controls the temperature in a thermal anti-icing system?
Hot and cold air are mixed.
What are the sources of heat for thermal anti-icing systems?(where is the hot air coming from)
-Bleed air from compressor
-engine exhaust heat
-combustion heaters.
What prevents overheating of the leading edges of a thermal anti-ice system operated by engine bleed air?
Overheat sensors signal the anti-icing valves to close and shut off the hot air.
What happens to the hot air used by a thermal anti-ice system after it has heated the surface?
The air is dumped (exhausted) overboard.
Why is it necessary to provide overheat protection for anti-icing systems that use turbine engine bleed air?
The air is hot enough to cause damage to the aircraft structure.
What are the effects of arcing on an electrically heated windshield?
Localized overheating and damage to the windshield.
Can the operation of an electrically heated pitot-tube be checked with the aircraft’s ammeter, and if so, how?
Yes, turn the pitot heater on and observe the deflection of the ammeter needle.
What are several potential problems associated with electrically heated windshields?(what can go wrong with them)
-Arcing
-delamination
-scratches
-discoloration
Why do some pneumatic deicer boot systems have an electrically operated timer?
To automatically cycle the boots, provide the proper rest time, and then recycle the boots.
What are the two common methods of inflating pneumatic deicer boots?
Bleed air from a turbine engine or the exhaust from an engine-driven vacuum pump.
What procedure is used to hold deicer boots flat with the airfoil surface during flight?
Suction is applied to the boots.
Why do some deicer boot systems incorporate an oil separator?
If a wet pump system is used, the oil must be removed before it reaches the boots because oil damages the rubber.
What methods are used to attach a deicer boot to the leading edges of the wing and tail surfaces?
Adhesives, fairing strips and screws, or a combination of both.
What important step should be taken prior to making a cold-patch repair to a deicer boot?
Consult the manufacturer’s service manual and follow the repair instructions explicitly.
Describe the methods commonly used to remove rain from a windshield.
Windshield wipers, a blast of air, or chemical rain repellant.
What power sources are used to operate windshield wipers?
Electricity or hydraulic pressure.
Name two problems associated with in-flight operation of aircraft windshield wipers.
Insufficient blade pressure caused by aerodynamic forces and failure to oscillate fast enough.
Describe the operation of a pneumatic rain removal system.
A high velocity air blast prevents the rain from reaching the surface of the windshield.
What are the effects of spraying rain repellant on a dry windshield?
It smears and streaks, which reduces visibility, and it is hard to remove when dry.
Where would you find information on the acceptable limits of windshield delamination?
In reference material provided by the manufacturer.
Is there any special requirement as to the type of oxygen used in an aircraft system?
Only aviator’s breathing oxygen should be used.
Describe the operating principle of a continuous-flow oxygen system.
High-pressure oxygen flows from the storage cylinder to a pressure regulator where its pressure is reduced and then to the mask outlets whenever the system is turned on.
Describe the operating principle of a pressure-demand oxygen system.
Demand systems allow oxygen to flow from the cylinder to the regulator and then to the mask only when the user inhales. Pressure-demand systems provide oxygen to the mask at higher than atmospheric pressure when used at extremely high altitudes, forcing oxygen into the user’s lungs.
What should be used to purge an oxygen system of moisture?
Oxygen, dry air, or dry nitrogen.
What action must be taken when an oxygen system has been open to the atmosphere?
The system must be purged of any moisture.
Describe the safety precautions that should be observed when servicing oxygen systems.
Avoid all contact with petroleum-based oil or grease, don’t smoke, keep everything very clean, service systems outdoors if at all possible, and keep the caps on the bottles to protect the valves.
What is a Roots blower?
A type of engine-driven compressor.
Name two different types of independent cabin air compressors.
Positive-displacement and centrifugal.
What is the source of pressurization air in most jet aircraft?
Engine bleed air.
What device provides the principle means of controlling cabin pressure?
The outflow valve.
What unit regulates the position of an outflow valve?
The cabin pressure controller.
Name several methods used on reciprocating-engine aircraft for providing HEATED cabin air.
Exhaust shroud heat exchangers, combustion heaters, and electric heaters.
What is the function of the ventilating air in a combustion heater?
-transports the heat into the cabin -prevents combustion gases from entering the cabin if the combustion chamber develops a crack.
What are the SOURCES of ventilating air in a combustion heater?
Ram air
a blower
possibly a compressor
Name the basic components of an AIR-cycle cooling system.
The compressor and expansion turbine, heat exchangers, and various valves.
Describe the basic operating principles that allow an air-cycle system to produce cool air.
engine bleed air is cooled in the primary heat exchanger, compressed, then cooled again in the secondary heat exchanger. This air is expanded across the turbine where energy is extracted and the pressure is reduced. This produces a large temperature drop.
Describe the basic operating principles of a water separator.
Cool, moist air is swirled so that water droplets are separated by centrifugal force, captured by a sock, and drained.
Name the principle components of a vapor-cycle system.
A compressor, condenser, expansion valve, and an evaporator.
In what significant way is a vapor-cycle cooling system different from an air-cycle system?
Vapor-cycle systems use a refrigerant liquid, usually Freon®.
Why is oil added to the refrigerant in a vapor-cycle air conditioning system?(what does oil do)
To lubricate the compressor.
Why do some aircraft have fuel jettison systems?
To allow the crew to reduce the weight of the aircraft down to or below the maximum allowable landing weight.
Is there any reason why a fuel jettison system might be required on a small aircraft?
Yes, if the maximum takeoff weight exceeds the maximum allowable landing weight, a jettison system would be required.
What are some other names for a single-point fueling system?
-underwing
-pressure fueling system.
Why do multi-engine airplanes have fuel crossfeed systems?
To allow any engine to draw fuel from any tank.
The fuel selector valve for a multi-engine aircraft must have at least three positions. What are they?
ON, OFF, and Crossfeed.
Why do some fuel tanks have internal baffles?
To resist fuel surging or sloshing caused by changes in the attitude of the aircraft.
What are the two types of fuel compartments?
Integral or wet wing fuel cells, and bladder-type fuel cells.
What does the term ‘wet wing’ mean?
It means that sealed portions of the aircraft wing structure form the fuel tank(s).
How is the weight of the fuel supported when bladder-type fuel cells are used?
The bladder is supported by the aircraft structure which contains it.
Why do turbine-engine aircraft have fuel temperature indicating systems?
To allow the crew to determine if the fuel is cold enough to produce a danger of the formation of ice crystals.
Name four types of fuel quantity gauging systems currently in use. (how do you read it)
Sight gauges, mechanical, electric, and electronic gauges.
Why are electronic (capacitance-type) fuel quantity indicating systems more accurate than other types?
They measure the mass of the fuel instead of the volume.
What are drip gauges and sight gauges?
Underwing, bayonet-type fuel gauges.
What is the purpose of an in-transit light associated with an electrically operated fuel tank shutoff valve?
To provide an indication that the valve is in motion between one position and another.
For what reason is a fuel jettison system usually divided into two separate, independent systems, one for each wing?
To help maintain lateral stability by jettisoning fuel from a heavy wing if necessary.
What procedures should be followed regarding gaskets and seals when replacing fuel system components?
All old gaskets and seals should be replaced with new ones.
Is it possible for a fuel system to develop a leak that has no visible evidence such as a stain or spot, and if so, how?
An internal component such as a valve could develop a leak.
How is a fuel tank checked for leaks following a patch or welded repair?
The tank is slightly pressurized with air and the repaired area is leak-checked with a soap and water solution.
Name some advantages of a single-point fueling system.
It reduces fueling time, reduces chances for contamination and fire, and eliminates damage to the aircraft skin.
Why should you wait for a period of time after fueling an aircraft before checking the fuel sumps?
To allow time for water and contaminants to settle to the drain point.
Briefly describe the components of a thermal switch fire detection system.
Temperature sensitive switches that complete a circuit at a specific temperature and trigger a warning.
Are thermal switches wired in series or in parallel with each other?
Parallel.
How are the detector units in a double-loop Fenwal system wired?
In parallel between two complete loops of wiring.
In what way is a thermocouple fire warning system different from a thermal switch system?
Thermocouple systems are sensitive to the rate of temperature change, whereas thermal switch systems respond to a specific temperature value.
Briefly describe the components of a Kidde continuous loop fire detection system.
A Kidde system has an Inconel loop whose resistance changes with temperature.
Briefly describe the components and operation of a Lindberg fire detection system. (hindenburg)
A stainless steel tube contains an inert gas and a discrete material that absorbs some of the gas. When the tube heats up, some gas is released, raising the pressure in the tube, which activates a pressure switch.
Describe the process or mechanism by which a photoelectric smoke detector generates a warning of a possible fire.
Smoke particles refract light in the detector unit causing the photoelectric cell to conduct electricity and trigger the alarm.
How can the operation of a photoelectric smoke detector be tested?
By actuating a test switch.
Name two types of smoke detection systems used in aircraft.
Light refraction (photoelectric) types and ionization types.
What are the usual locations where a carbon monoxide detector would be installed?
In an aircraft cockpit or cabin.
How does a carbon monoxide detector indicate the presence of this deadly gas?
The tan spot on the detector turns gray or black.
What are the possible effects of kinks and sharp bends in the sensing element(s) of a fire warning system?
False fire warnings caused by short circuits.
How is a Freon container checked for proper pressure?
A chart must be used to determine the maximum and minimum gauge pressure readings based on the ambient temperature.
Name the two basic types of fire extinguishing systems.
The conventional system and the high-rate discharge system.
Name the extinguishing agent most commonly used by conventional fire extinguishing systems.
Carbon dioxide (CO2).
Name the extinguishing agent most commonly used by high-rate discharge fire extinguishing systems.
Halon (Halogenated hydrocarbon type agents), also known as Freon.
How are Freon bottles protected from excessively high temperatures and how can you tell that this has occurred?
A thermal fuse (or blowout disk) will release the agent if the bottle temperature exceeds a certain limit. This blows out a red indicator disk.
What condition is indicated if the yellow disk is missing in a fire extinguishing system?
The system has been discharged normally.
Describe the mechanism by which a Freon bottle is discharged.
An electrical signal fires an explosive squib, which ruptures a frangible disk.
How is the service life of a discharge cartridge calculated?
From the date stamped on the cartridge by the manufacturer.
Where do you find the regulation that specifies the operating conditions that make 100-hour inspections mandatory?
FAR Part 91.
A certificated Airframe & Powerplant mechanic may sign off and approve the return to service following what type of inspection?
A 100-hour inspection.
Under what conditions may a mechanic perform an annual inspection and return the aircraft to service?
The mechanic must hold an Inspection Authorization.
What is the time frame within which an annual inspection must be performed if such an inspection is required?
Within the preceding 12 calendar months.
Under what conditions may any checklist be used as a guide for a 100-hour inspection?
The checklist must meet the minimum standards specified in FAR Part 43, Appendix D.
May an aircraft that is overdue for an annual inspection be flown to a place where the inspection can be performed?
Yes, provided a ferry (special flight) permit is obtained.
In order for an individual person to conduct a 100-hour inspection and approve the return to service, that person must have what type of certificate(s)?
A mechanic’s certificate with both the Airframe and Powerplant ratings.
An aircraft is required by FAR 91.409 to have a 100-hour inspection. Is it legal to fly that airplane beyond the inspection requirement, and if so, for how long?
Yes, the aircraft may be operated for up to 10 hours, if required, to reach a place where the inspection can be accomplished.
An airplane is flown 4 hours over the 100-hour inspection limit to reach your maintenance facility. How do you account for those 4 hours?
The 4 hours are included in the next 100 hours time-in-service period.
What types of operations require that aircraft operating under Part 91 must undergo 100-hour inspections?($$$$)
Aircraft operated for compensation or hire, or used for flight instruction when provided by the flight instructor.
An aircraft under a progressive inspection program is operated for compensation or hire. Does it need a 100-hour inspection?
No, progressive inspections replace 100-hour inspections.
Who is authorized to supervise a progressive inspection?
Certificated A&P mechanics who hold an Inspection Authorization, certified repair stations, or the aircraft manufacturer.
When a progressive inspection program is discontinued, at what time is the next 100-hour inspection due?
100 hours after the last complete inspection of the progressive program.
An owner desires to use a progressive inspection program. To whom does the owner apply for authorization?
To the FAA Flight Standards District Office having jurisdiction over the area where the owner is located.
Is an engine run-up required as part of a 100-hour inspection on a turbine-powered aircraft?
Yes.
Where would you locate the required items that must be recorded in the aircraft maintenance records following completion of a 100-hour inspection?
FAR Part 43.
Where might you locate a sample of the recommended statement for recording the approval for return to service of an aircraft following completion of an annual or 100-hour inspection?
FAR Part 43.
Where would you look to find approved information for work on an aircraft electrical system?
In the manufacturer’s maintenance manual or other instructions for continued airworthiness.
What are the limitations placed on mechanics with regard to propellers?
Mechanics may not perform major repairs to, or alterations of, propellers.
After equipment is installed in accordance with an STC, who must approve the return to service?
An A&P mechanic who holds an Inspection Authorization.
