Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
374 Cards in this Set
- Front
- Back
|
Aircraft Structural Assembly & Rigging |
Aircraft Structural Assembly & Rigging |
|
|
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, & vertical. |
|
|
What are the three primary flight controls of an aircraft? |
The ailerons, elevator, & rudder. |
|
|
Name several secondary flight controls & describe their general purpose? |
Secondary flight controls consist of various high-lift devices used during low-speed fight such as leading & trailing edge flaps, slats, slots, speed brakes, etc. |
|
|
Name several types of auxiliary flight controls & describe their general purpose? |
The auxiliary flight controls consist of the various types to trim tabs such as balance tabs, anti-servo & servo tabs, & spring tabs. Their function is to assist the pilot in moving the controls & to trim the aircraft to fly hands-off. |
|
|
What is a servo trim tab? |
It is an auxiliary control, positioned by the movement of a cockpit control & designed to create aerodynamic forces to assist in moving a control surface. |
|
|
What is a spring tab? |
It is an auxiliary control designed to aid the movement of a primary control at high speeds when control forces become high. |
|
|
What is a balance trim tab? |
It is an auxiliary control designed to create aerodynamic forces to assist in moving a control surface. the tab is 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? |
Leading & trailing edge flaps, slats, and slots. |
|
|
Describe some of the tools used to check control surface travel? |
A universal propeller protractor or 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? |
The ambient temperature & the cable size. |
|
|
What is the function of a cable tension regulator? |
It automatically adjust the cable tension to compensate for expansion & 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 controls 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. |
|
|
Sheet Metal Structures |
Sheet Metal Structures |
|
|
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. |
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 & 1/2 the shank diameter in height. |
|
|
Describe the markings found on the heads of A, B, D, AD, & DD rivets. |
A rivets are plain, B rivets have a cross, D rivets have a raised dot, AD rivets have a dimple, & DD rivets should 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 & 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, & HuckLok rivets. |
|
|
What is the difference between the tools required to pull a CherryLOCK rivet & a CherryMAX rivet? |
CherryLOCK rivets require a tool for each different size & 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 & 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 & spacing should be used for a single row of protruding head rivets? |
Not less than two rivet diameters from the edge & 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 actions is taken to prevent cracks from forming while dimpling magnesium or some hard sheet metals? |
Hot dimpling equipment is used to preheat & 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 & weight bucking bar when performing sheet metal riveting? |
If a bucking bar is too large or heavy it may be difficult to control & 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 & 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 & 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 & setback. |
|
|
What factors must be considered in order to determine setback? |
The thickness of the metal & the bend radius. |
|
|
What is done to a corner where two bends intersect to prevent cracking? |
Relief holes are drilled on the corner. |
|
|
What are the two reasons for installing a lightening hole in a sheet metal wing rib? |
Lightening holes reduce the weight & increase the stiffness. |
|
|
Describe a joggle & 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 & thickness as the original structure. |
|
|
Wood, Composite, & Transparent Plastic Structures |
Wood, Composite, & Transparent Plastic Structures |
|
|
What are 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. |
Knots, checks, splits, pitch pockets, cross grain, decay, dry rot, etc. |
|
|
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? |
Casein glue. |
|
|
What are the three types of glues used in modern aircraft construction & repair? |
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 apply the proper clamping pressure to a glue joint? |
Clamping forces air out of the joint, brings the wood surfaces together evenly & is, in part, responsible for the 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 & discolored areas? |
Stains & discoloration usually accompany decay and/or rot. |
|
|
Describe the acceptance methods used to repair elongated bolt holes found in a wooden wing spar. |
Remove the section containing the elongated hole(s) & splice in a new section or replace the entire spar. |
|
|
What types of joint is used to splice a solid or rectangular wood spar? |
A scarf joint. |
|
|
In what areas are splices to a wood spar prohibited? |
Under an attachment fitting for the wing root, landing gear, engine-mount, lift, or inter-plane strut. |
|
|
What is the maximum number of splices allowed for any single spar? |
Two. |
|
|
Describe the characteristics of a scarf joint. |
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 & aircraft skin. |
|
|
Provide examples of at least three types of plywood skin repairs. |
Splayed 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? |
A splayed patch may be used if the hole can be cleared out to a diameter of less than 15 thickness of the skin. |
|
|
What should be done to prevent a plywood patch & the pressure plate from sticking together if glue is extruded from the joint? |
Place a piece of waxed paper or vinyl plastic between the patch & the pressure plate. |
|
|
Why are lightweight steel bushings sometimes used in wooden structures? |
Bushing 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 & core materials used in bonded honeycomb structures intended for special applications. |
Stainless steel, titanium, magnesium, plywood, glass, nylon, & cotton cloth. |
|
|
Describe the construction of a bonded honeycomb structure. |
It is a laminated structure that has a solid facing bonded to either side of a core consisting of open, six-sided cells. |
|
|
What must be done with a damaged area in a bonded honeycomb structure prior to beginning repairs? |
The damaged area must be completely removed. |
|
|
A drill bit used for drilling composites should have an included angle of how many degrees? |
135 degrees. |
|
|
What are the most common causes for delamination of a composite structure? |
Sonic vibration, expansion of internal moisture, liquid leakage, & a 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 & windshields? |
Exposure to ultraviolet light, stress, solvents, & improper handling. |
|
|
How should a hole be drilled in Plexiglass to avoid damage to the hole when the drill breaks through to the underside? |
Back up the plastic with a piece of wood & feed the drill slowly. |
|
|
Aircraft Welding |
Aircraft Welding |
|
|
Name the three principle types of welding. |
Gas welding, electric arc welding, & electric resistance welding. |
|
|
What are some advantages of gas shielded arc welding? |
The weld is stronger, more ductile, & 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? |
The 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 & 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 & properly tinned. |
|
|
What is the preferred method for welding aluminum? |
Tungsten Inert Gas (TIG) welding |
|
|
What is the preferred method of welding magnesium? |
Tungsten Inert Gas (TIG) welding |
|
|
What precautions must be observed in order to weld titanium? |
All traces of oxygen & 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 & adjust the gas pressure accordingly. |
|
|
What factors determine the amount of heat delivered by a gas welding torch? |
The size of the torch tip & the 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 & 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? |
The inner tube could be chilled with dry ice or in a freezer while the outer tube could be heated slightly with a torch. |
|
|
Aircraft Fabric Covering |
Aircraft Fabric Covering |
|
|
Aircraft fabric covering fabrics are made of materials from what two sources? |
Organic materials & synthetic materials. |
|
|
How would you determine the strength requirement for fabric used to re-cover an aircraft? |
The fabric must be of at least the quality & strength of the fabric used by the original manufacturer. |
|
|
What two types of organic fibers are used for covering aircraft? |
Cotton & linen. |
|
|
What is meant by warp, weft, & bias? |
Warp is the direction 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 warp & weft. |
|
|
What is the purpose of the selvage edge on a roll of a fabric? |
It prevents the fabric from unraveling. |
|
|
What identification marking is found on the selvage edge, & in which direction is the warp applied? |
The FAA-PMA stamp is found on the selvage edge & the warp is applied parallel to the line of flight. |
|
|
How are the fabric type & strength requirements determined for fabric-covered aircraft? |
The original manufacturer determines the fabric type, & the strength requirements are a function of the never exceed speed & 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 & mildew? |
Fiberglass |
|
|
What is the function or purpose of reinforcement tape? |
Reinforcement tape is used between the fabric & the rib stitching to prevent the lacing cord from cutting through the fabric. |
|
|
Where would you use surface tape? |
Over rib stitching & sewed seams, over lapped edges, around corners, & along leading & trailing edges. |
|
|
How should the edges of drainage, inspection, & ventilation holes be reinforced? |
With plastic, aluminum, or brass grommets. |
|
|
What are the principle methods used to test the condition of fabric? |
Punch testers such as the Maule or Seybolt tester, & 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 & prior to covering? |
Treat it with a protective coating of paint or varnish as appropriate. |
|
|
What is the principle 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, & 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 |
|
|
Aircraft Painting and Finishing |
Aircraft Painting and Finishing |
|
|
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? |
Cellulose Nitrate & 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 & runs? |
Inadequate surface preparation or paint sprayed too thickly. |
|
|
What components or parts of the airframe must be protected from damage when using paint stripper? |
Windshields & windows, plastics, composites, synthetic rubber, & fabrics. |
|
|
What is the function of zinc-chromate or wash primers? |
Primers serve to inhibit corrosion & provide a good bond between the metal & the topcoats. |
|
|
Name several common types of paint used on aircraft. |
Zinc-chromate & wash primers, synthetic enamels, acrylic lacquer, & polyurethane. |
|
|
What is the proper thinner to use with zinc-chromate primer? |
Toluene |
|
|
What health & safety precautions must be observed when using the toxic solvents & 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 & 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 thinner that dries too fast, cold temperatures, or a 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, & spraying. |
|
|
What is the effect on paint finishes if too much drier is added to the paint? |
The paint film will be brittle & tend to crack & peel. |
|
|
What paint system(s) may be used with epoxy topcoats? |
Any paint system in good condition. |
|
|
Airframe Electrical Systems |
Airframe Electrical Systems |
|
|
What could cause an AC electric motor to run too fast? |
Excessive applied voltage or shorter field windings. |
|
|
What tool is used to check a motor or generator armature for shorts & opens under load conditions? |
A Growler. |
|
|
When using a Growler, what indication will occur when a short exists between an armature segment? |
When a metal blade is held over the armature & a short exists in a segment, the blade will begin to vibrate & "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 & 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 the electrical system. |
Landing gear, cowl & 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, & protective device capacity will not be exceeded. |
|
|
What factors should be considered when determining the wire size for a particular application? |
The system voltage, permissible voltage drop, current to be carried, wire length & whether the load is continuous or intermittent. |
|
|
What is the relationship between the inside diameter of a conduit & 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. |
|
|
What is the proper length for a bonding jumper? |
As short as practical, but long enough to allow free movement of the component. |
|
|
Under what conditions must a switch be derated from its nominal rating? |
When used with inductive circuits, circuits with high in-rush current, & 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 slowly? |
Lack of lubrication, defective wiring, or low applied voltage. |
|
|
What would be done when making bonding or grounding connections between dissimilar materials? |
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? |
The power must be turned off. |
|
|
Hydraulic & Pneumatic Power Systems |
Hydraulic & Pneumatic Power Systems |
|
|
What materials from the bases of the three types of hydraulic fluids? |
Vegetable, mineral, & phosphate-esters. |
|
|
What colors denote mineral-based & phosphate-ester-based hydraulic fluids? |
Mineral based fluids are red & phosphate-ester based fluids are light purple. |
|
|
What are the results of exposing lacquers, oil-based paint, plastic resins, & 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. |
Hand pumps, engine-driven pumps, & electrically driven pumps. |
|
|
What would cause the bypass valve in a hydraulic filter to open & allow unfiltered fluid to circulate in the system? |
A clogged filter element. |
|
|
Describe several methods of pressurizing a hydraulic reservoir. |
Engine bleed air, system pressure acting on a small piston in the reservoir, using 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 & delivered to the outlet side as the gears rotate. |
|
|
Describe the purpose of a pressure regulator. |
Pressure regulators manage the output of the pump to maintain system pressure. They allow the pump to be unloaded so it turns without significant 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? |
Piston, diaphragm, & 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 & contaminants. |
|
|
Aircraft Landing Gear Systems |
Aircraft Landing Gear Systems |
|
|
What is the purpose of a torque link on an oleo strut? |
To keep the wheel in alignment & 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, & 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 precautions must be taken when removing a wheel from an axel or when disassembling a wheel? |
Verify that the tire is completely deflated before removing a wheel from an axel 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 & retract landing gear? |
Hydraulic pressure & electric motors. |
|
|
At what times should a gear retraction check be performed? |
During annual or other inspections & following a hard landing. |
|
|
What mechanism(s) ensure that a nose wheel is not turned as it retracts into its wheelwell? |
Internal centering cams in the strut or an external track. |
|
|
Name several types of brake actuating systems. |
Independent master cylinders, boosted brakes, & 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. |
A pressure pot can be attached to the bleeder valve & fluid forced back towards the master cylinder and/or reservoir, or the master cylinder can be used for forcing fluid from the 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, & more tread wear on the shoulders than in the center. |
|
|
Position and Warning Systems |
Position and Warning Systems |
|
|
What unit is 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, & a red warning light or lights. |
|
|
How can a pilot determine that the landing gear is down & 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 or trailing edge flap position, stabilizer position, or speed brake not stowed. the manufacturer may establish other conditions. |
|
|
What landing gear positions must be indicated by regulations? |
Down & locked & up & lock. |
|
|
Under what conditions will a landing gear aural warning sound? |
When the throttle is retarded & the landing gear is not down & locked. |
|
|
How does a takeoff configuration warning differ from a landing gear warning? |
Takeoff warnings are usually an intermittent horns while landing gear warnings are 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) & 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 be normally 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 & locked, how will the switches be connected, in series or in parallel? |
In series. |
|
|
Where would you locate the procedures for checking & 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 & warning system? |
To alert the crew that a malfunction has occurred & corrective action may be required. |
|
|
Aircraft Instrument Systems |
Aircraft Instrument Systems |
|
|
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. |
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? |
Engine RPM |
|
|
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? |
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? |
(1) The fluid must be clear. (2) the housing must be full with no bubbles. (3) The card must be legible & the lubber line intact. (4) The compass should be properly calibrated. |
|
|
In what way do magnetic fields generated by electrical equipment & 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? |
The altimeter, vertical speed indicator, airspeed & mach meter in high-performance jets. |
|
|
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 & how is it accomplished? |
To compensate for deviations, caused by magnetic fields in the aircraft, by adjusting the compensating magnets. |
|
|
Aircraft Avionics Systems |
Aircraft Avionics Systems |
|
|
What are the basic components of a radio communication system? |
A microphone, transmitter, & receiving antennas, receiver, & speaker or headphones. |
|
|
What frequency range is used by most modern voice communications system? |
The VHF (Very High Frequency) band (118.0 to 136.975 MHZ) |
|
|
What does the term "ADF" stand for? |
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 & a visual display indicator. |
|
|
What does DME stand for? |
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 & 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 & 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 & 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, a controller, & an amplifier or computer. |
|
|
What are the sensing elements of an autopilot system? |
Attitude, directional, & turning gyros, & an altitude sensor. |
|
|
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. |
The cable should be supported every 2 feet, bends should be 10 times the cable diameter, & it should be routed separately from other wires. |
|
|
Airframe Ice and Rain Control |
Airframe Ice and Rain Control |
|
|
What controls the temperature in a thermal anti-icing system? |
Hot & cold air are mixed. |
|
|
What are the sources of heat for thermal anti-icing systems? |
Bleed air from the compressor section of a turbine engine, engine exhaust heat exchangers & 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 & 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 & 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 & observe the deflection of the ammeter needle. |
|
|
Describe several potential problems associated with electrically heated windshields. |
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 the oil damages the rubber. |
|
|
What methods are used to attach a deicer boot to the leading edges of the wing & tail surfaces? |
Adhesives, fairing strips & 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 & follow the repair instructions explicitly. |
|
|
Describe the methods commonly used to remove rain from 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 & 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 & streaks, which reduces visibility, & 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. |
|
|
Cabin Atmosphere Control Systems |
Cabin Atmosphere Control Systems |
|
|
Is there any special requirement as to the type of oxygen used in an aircraft system, and if so, what is it? |
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 & 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 & 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, & 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 & 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, & electric heaters. |
|
|
What is the function of the ventilating air in a combustion heater? |
Ventilating air transports the heat from the heater 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 in flight, a blower on the ground, or possibly a compressor if the airplane is pressurized. |
|
|
Name the basic components of an air-cycle cooling system. |
The compressor & expansion turbine, heat exchangers, & various valves. |
|
|
Describe the basic operating principles that allow an air-cycle system to produce cool air. |
Hot 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 & 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 the water droplets are separated by centrifugal force, capture by a sock, & drained. |
|
|
Name the principle components of a vapor-cycle system. |
A compressor, condenser, expansion valve, & 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? |
To lubricate the compressor. |
|
|
Aircraft Fuel Systems |
Aircraft Fuel Systems |
|
|
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? |
An underwing or 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 cells? |
Integral or wet wing fuel cells, & 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. |
Sight gauges, mechanical, electric, & 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 & 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 & seals when replacing fuel system components? |
All old gaskets & 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, & 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 & the repaired area is leak-checked with a soap & water solution. |
|
|
Name some advantages of a single-point fueling system. |
It reduces fueling time, reduces chances for contamination & fire, & 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 & contaminants to settle to the drain point. |
|
|
Fire Protection Systems |
Fire Protection Systems |
|
|
Briefly describe the components of a thermal switch fire detection system. |
Temperature sensitive switches that complete a circuit at a specific temperature & 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 tube containing two wires embedded in a thermistor core material whose resistance changes with temperature. |
|
|
Briefly describe the components & operation of a Lindberg fire detection system. |
A stainless steel tube contains an inert gas & 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 & 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 & 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 & 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 & minimum gauge pressure readings based on the ambient temperature. |
|
|
Name the two basic types of a fire extinguishing systems. |
The conventional system & 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 & how can you tell that this has occurred? |
A thermal fuse (or blowout disc) will release the agent if the bottle temperature exceeds a certain limit. This blows out the red indicator disc. |
|
|
What condition is indicated if the yellow disc 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. |
|
|
Aircraft Airworthiness Inspection |
Aircraft Airworthiness Inspection |
|
|
Where do you find the regulation that specifies the operating conditions that make 100-hour inspections mandatory? |
FAR part 91.409 |
|
|
A certificated Airframe & Powerplant mechanic may sign off & approve the return to service following what type of inspection? |
A 100-hour inspection. |
|
|
Under what conditions may a mechanic perform an annual inspection & 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 & approve the return to service, that person must have what type of certificate(s)? |
A mechanic's certificate with both Airframe & 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, & 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 Standard 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 propeller? |
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. |
