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Module 7 Maintenance practices: 50 practice questions

Real EASA paper: Category A 76 Q / 95 min · B1.1 80 Q / 100 min · B1.2 80 Q / 100 min · B1.3 80 Q / 100 min · B2 60 Q / 75 min · B2L 60 Q / 75 min · B3 80 Q / 100 min. Three options, 75% to pass. Answer key on the last page. From part66exam.com · independent study aid, not an official exam or a past paper.

  1. 1. Before an engine ground run, the area behind the aircraft is checked mainly because of:

    1. A. the risk of the aircraft rolling back
    2. B. noise damage to hangar windows
    3. C. the jet blast or propwash hazard

  2. 2. Protective sleeving or conduit is added to a wire bundle where it:

    1. A. runs in a clean, protected area
    2. B. must be easily identifiable
    3. C. passes near sharp edges or abrasion risks

  3. 3. A roller chain is checked for stretch (wear) by:

    1. A. measuring a set number of links
    2. B. weighing the chain on scales
    3. C. checking the chain's colour

  4. 4. Removing an item located aft of the CG will move the CG:

    1. A. aft
    2. B. nowhere
    3. C. forward

  5. 5. A measured free length shorter than the minimum in the maintenance data indicates that the spring:

    1. A. has been correctly preloaded for its installation
    2. B. has taken a permanent set and should be rejected
    3. C. is new and has not yet settled to its free length

  6. 6. A borescope is used on turbine engines to:

    1. A. inspect internal parts without disassembly
    2. B. measure blade tip clearances in flight
    3. C. detect internal cracks in shafts

  7. 7. Defects reported by the crew and their rectification are recorded in the:

    1. A. illustrated parts catalogue
    2. B. flight crew licence
    3. C. aircraft technical log

  8. 8. A dimension on a drawing is shown as 50 +0.05 / -0.00 mm. This is:

    1. A. a bilateral tolerance
    2. B. a unilateral tolerance
    3. C. a basic dimension without tolerance

  9. 9. Scribing lines with a steel scriber on aluminium sheet within the finished part should be avoided because:

    1. A. scratches act as stress raisers
    2. B. they make the metal magnetic
    3. C. they increase the bend allowance

  10. 10. Cleco fasteners are used during riveting to:

    1. A. hold the sheets aligned for riveting
    2. B. replace rivets permanently in a joint
    3. C. measure the size of rivet holes

  11. 11. Limits for twist in a part such as a propeller blade or rod are checked by:

    1. A. weighing the part on precision scales
    2. B. measuring angles at set stations
    3. C. tapping it and listening to the tone

  12. 12. A bearing is to be heated to aid fitting on a shaft. The correct method is:

    1. A. in an oil bath or oven, temperature controlled
    2. B. with an oxy-acetylene torch on the race
    3. C. in an open fire until it glows

  13. 13. Critical fatigue areas on control cables are where the cable:

    1. A. passes over pulleys or through fairleads
    2. B. runs straight through open bays
    3. C. is painted for identification purposes

  14. 14. In a dimension given as 25.00 ± 0.05 mm, the tolerance is:

    1. A. 0.10 mm total
    2. B. 0.05 mm total
    3. C. 25.05 mm

  15. 15. In lightning zoning, areas such as the nose, wing tips and engine nacelles, where a strike first attaches, are:

    1. A. zone 1 (initial attachment)
    2. B. zone 2 (swept stroke)
    3. C. zone 3 (conduction only)

  16. 16. Which three elements must all be present for a fire to occur?

    1. A. Fuel, heat and oxygen
    2. B. Fuel, water and nitrogen
    3. C. Heat, pressure and humidity

  17. 17. A time domain reflectometer (TDR) is used on aircraft wiring to:

    1. A. measure the insulation resistance
    2. B. measure the supply frequency
    3. C. locate opens, shorts and chafes

  18. 18. Bead-and-clamp hose connections on rigid tubes are suitable for:

    1. A. low- or medium-pressure systems such as coolant
    2. B. high-pressure hydraulic systems up to 3000 psi
    3. C. high-pressure oxygen supply lines from cylinders

  19. 19. When work cards are held in an electronic database, Part-145 requires a backup database that is updated within:

    1. A. 7 days of an entry in the main database
    2. B. 24 hours of an entry in the main database
    3. C. the next scheduled maintenance check

  20. 20. During over-wing refuelling, when should the nozzle be bonded to the aircraft?

    1. A. Before the fuel tank cap is opened
    2. B. After fuel has started to flow into the tank
    3. C. Only if fuel is spilled

  21. 21. A wire bundle routed close to a moving control rod must have:

    1. A. slack so it can touch the rod
    2. B. adequate clearance and secure clamping
    3. C. no clamps so it can move freely

  22. 22. Torque tubes in a flight control or flap drive system are inspected for:

    1. A. their electrical resistance only, using a bonding meter
    2. B. internal hydraulic fluid leaks
    3. C. twist, corrosion, cracks and joint wear

  23. 23. After equipment is installed in an aircraft, the weight and balance record is updated using:

    1. A. only the item's purchase price
    2. B. its mass and arm to recompute empty CG
    3. C. a new flight test of the aircraft

  24. 24. The free length and load test of a spring are typically recorded on:

    1. A. the aircraft technical log, as a defect entry
    2. B. the workshop worksheet or component record for that unit
    3. C. the tool calibration record for the tester

  25. 25. After reassembly of a system, the final step before release is to:

    1. A. paint over all of the fasteners
    2. B. carry out the functional or leak test
    3. C. remove the safety locking devices

  26. 26. In an independent inspection, the independent qualified person:

    1. A. issues the CRS for the task
    2. B. checks the task but does not issue the CRS
    3. C. must come from another organisation

  27. 27. In orthographic projection, each view shows:

    1. A. the object as seen from one direction at right angles
    2. B. the object in perspective with vanishing points
    3. C. the object tilted to show three faces at once

  28. 28. A Part-145 organisation wants to 3D-print a structural replacement part for an aircraft. This is:

    1. A. allowed for any part if a high-quality printer is used
    2. B. allowed if the printed part looks identical to the original
    3. C. only permitted with approved data and approved processes

  29. 29. Why are 2024 (DD) rivets stored in a freezer after heat treatment?

    1. A. To delay age hardening so they stay soft enough to drive
    2. B. To prevent corrosion of the rivet surface during long storage
    3. C. To shrink them so that they fit the holes

  30. 30. A 20 mm hole is toleranced +0.000/+0.025 mm and its shaft -0.010/-0.030 mm. What is the maximum clearance?

    1. A. 0.010 mm
    2. B. 0.035 mm
    3. C. 0.055 mm

  31. 31. A bearing outer race shows scoring on its outside diameter and the housing bore is worn. The likely cause is that the race:

    1. A. has been turning in its housing
    2. B. was over-lubricated
    3. C. was cleaned in the wrong solvent

  32. 32. During rigging, the controls are held in the neutral position by:

    1. A. rig pins or blocks
    2. B. the gust lock only
    3. C. a person holding the control column

  33. 33. Personal tools brought into an approved maintenance organisation must be:

    1. A. left unmarked to give more flexibility
    2. B. calibrated by the owner at home
    3. C. controlled by the organisation's tool system

  34. 34. An aircraft has exceeded its maximum operating speed (overspeed). Maintenance action normally includes:

    1. A. a structural inspection as specified in the AMM
    2. B. no action if the crew reports no vibration
    3. C. only a check of the airspeed indicator

  35. 35. Halon 1211 and 1301 extinguishers are most effective on:

    1. A. Class D metal fires only
    2. B. Class B fires and Class C fires
    3. C. wood and paper fires only

  36. 36. Which hacksaw blade is best for cutting thin-wall tubing?

    1. A. A blade with 14 teeth per inch
    2. B. A blade with 18 teeth per inch
    3. C. A blade with 32 teeth per inch

  37. 37. The size number (dash number) of a machine-threaded tube fitting indicates:

    1. A. the thread pitch of the fitting, in threads per inch of length
    2. B. the nominal tube outside diameter in sixteenths of an inch
    3. C. the maximum working pressure in hundreds of psi

  38. 38. Maintenance records made in an electronic system must be:

    1. A. deleted once the aircraft is released
    2. B. protected against unauthorised alteration
    3. C. printed and signed by the operator's pilot

  39. 39. When an aircraft is moored outdoors, control surfaces should be:

    1. A. left free so they can move with the wind
    2. B. secured with gust locks or control locks
    3. C. removed and stored

  40. 40. Where indirect marking (printed sleeves) is used on a cable, the sleeves are fitted at each end and at intervals not longer than:

    1. A. 6 ft (about 1.8 m)
    2. B. 15 in (about 38 cm)
    3. C. 20 ft (about 6 m)

  41. 41. A drive belt appears glazed and cracked. The correct action is:

    1. A. replace it and correct tension and alignment
    2. B. dress the belt with oil to soften it
    3. C. turn the belt inside out and refit it

  42. 42. Engine oil during weighing should be:

    1. A. drained completely in all cases
    2. B. topped up above the maximum mark
    3. C. in the condition the manual states

  43. 43. A spring load test checks that:

    1. A. the spring is attracted by a magnet
    2. B. it gives the specified force at a set length
    3. C. it has the specified number of coils only

  44. 44. Damage is found that exceeds the SRM's repairable limits. The technician should:

    1. A. use the nearest similar SRM repair
    2. B. obtain approved repair data
    3. C. blend it and return to service

  45. 45. Under M.A.504(b), an unsalvageable component may re-enter the supply system only if:

    1. A. it passes a detailed visual inspection in stores
    2. B. it is sold to another operator outside the EU
    3. C. its life limit is extended or a repair is approved

  46. 46. A drawing that shows a single part with all the information needed to make it is a:

    1. A. assembly drawing
    2. B. installation drawing
    3. C. detail drawing

  47. 47. A joggle formed in a sheet metal part is:

    1. A. a relief hole drilled at the intersection of two bends
    2. B. a crack caused by bending too tightly
    3. C. an offset bend that lets one part overlap another flush

  48. 48. Cleco fasteners are colour coded so that:

    1. A. their diameter can be recognised quickly
    2. B. their material can be identified
    3. C. they show how many times they have been used

  49. 49. A cylinder bore measures 101.60 mm near the top of the ring travel and 101.52 mm near the bottom, in the same direction. The taper is:

    1. A. 0.08 mm
    2. B. 0.04 mm
    3. C. 0.16 mm

  50. 50. When removing a bearing from a shaft with a puller, the pulling force should be applied to:

    1. A. the outer ring in all cases, whatever the fit of the rings
    2. B. the ring with the interference fit, normally the inner ring
    3. C. the cage, as it holds the rolling elements together

Answer key

  1. 1. C — Exhaust and propeller blast can blow people, vehicles and loose objects over. The intake area in front and the blast area behind must both be clear before a run.
  2. 2. C — Sleeving, conduit and grommets protect wiring from chafing at sharp edges, holes in structure and areas of abrasion or heat.
  3. 3. A — Chain wear shows as elongation. A set number of pitches is measured under light tension and compared with the maximum allowed length.
  4. 4. C — Taking weight off behind the CG reduces the aft moment, so the CG moves forward.
  5. 5. B — Loss of free length means the material has yielded or relaxed; the spring will give less force at its installed length.
  6. 6. A — Borescopes (rigid, flexible or video) are inserted through ports to inspect blades, vanes and combustors for damage, burning, cracks and FOD without taking the engine apart.
  7. 7. C — M.A.306: the technical log records defects, deferred defects, rectification and the CRS, and flight information needed for continuing airworthiness.
  8. 8. B — A unilateral tolerance allows variation in one direction only from the basic size (here 50.00 to 50.05 mm). A bilateral tolerance allows variation both ways, such as ±0.05.
  9. 9. A — Scratches from scribers can start fatigue cracks. Layout lines on the part are marked with a soft pencil or fine marker; scribers are only used on lines that will be cut away.
  10. 10. A — Clecos are spring-loaded temporary fasteners inserted in drilled holes to hold parts tightly together and in alignment while other holes are drilled and rivets installed.
  11. 11. B — Twist is the angular change along a part. It is checked by measuring angles at set stations (with protractors or fixtures) and comparing with the limits in the manual.
  12. 12. A — Controlled heating (oil bath, oven or induction heater) expands the inner race uniformly without exceeding the safe temperature. Flames cause local overheating and loss of hardness.
  13. 13. A — Areas where the cable bends or rubs (pulleys, sleeves, fairleads) and within about 1 ft of a swaged fitting are prone to wire breakage and are inspected closely.
  14. 14. A — The part may be between 24.95 mm and 25.05 mm, so the total tolerance (difference between limits) is 0.10 mm. ± 0.05 mm is the bilateral deviation.
  15. 15. A — Zone 1 surfaces are likely to receive the initial attachment; zone 2 surfaces are swept by the channel as the aircraft moves; zone 3 carries conducted current only. Inspection focuses on zones 1 and 2.
  16. 16. A — Fire needs fuel, heat and oxygen (the fire triangle). Extinguishing agents work by removing one of them: cooling removes heat, smothering removes oxygen, and removing the fuel starves the fire.
  17. 17. C — A TDR sends a pulse down the cable and times the reflections from impedance changes. This shows the distance to faults such as opens, shorts or chafed insulation, which is useful for coaxial and long wire runs.
  18. 18. A — The beaded fitting with a hose section and clamps is used only in low- or medium-pressure systems. Flared, flareless or permanent fittings are used for high-pressure systems.
  19. 19. B — 145.A.45(e): computer-generated work cards may be held electronically if the database is protected against unauthorised alteration and a backup database is updated within 24 hours after each entry in the main database.
  20. 20. A — The sequence is: ground the aircraft and truck, bond truck to aircraft, then bond the nozzle to the aircraft before opening the tank, so that any static potential is equalised before fuel vapour is present.
  21. 21. B — Bundles are clamped to keep clearance from moving parts through their full travel; contact would chafe the wiring or jam the control.
  22. 22. C — Torque tubes transmit rotary motion; they are checked for straightness and twist, corrosion, cracks, loose rivets or pins and play in universal joints and support bearings.
  23. 23. B — The change in mass and moment (mass x arm) is added to (or subtracted from) the basic empty mass and moment, and a new empty CG is calculated and recorded.
  24. 24. B — Component overhaul work, including spring checks, is recorded on the worksheet and supports the release certificate (EASA Form 1).
  25. 25. B — Operational, functional and leak tests confirm the system works correctly after reassembly. Locking is checked, not removed.
  26. 26. B — The independent qualified person attests the task was completed satisfactorily. The CRS is issued by the authorised person after the independent inspection.
  27. 27. A — Orthographic projection shows separate flat views (front, top, side), each looking straight at one face. Pictorial drawings such as isometric show three faces at once.
  28. 28. C — Parts must conform to approved design data. A maintenance organisation may fabricate only a restricted range of parts under 145.A.42(b)(iii) procedures; structural AM parts need approved data and qualified processes.
  29. 29. A — DD rivets are annealed (solution heat treated) and then refrigerated to retard natural age hardening. They are removed from the freezer just before use and driven while still soft.
  30. 30. C — Maximum clearance = largest hole - smallest shaft = 20.025 - 19.970 = 0.055 mm. Minimum clearance = smallest hole - largest shaft = 20.000 - 19.990 = 0.010 mm.
  31. 31. A — If the fit between race and housing is lost, the race rotates ('creeps') in the housing, scoring both. Both bearing and housing must be assessed against limits.
  32. 32. A — Rigging starts by locking the system in neutral with rig pins or blocks, then adjusting cable tension with the surfaces in neutral, and finally setting the stops.
  33. 33. C — All tools used, including personal ones, must be identified and controlled by the organisation's procedures. Measuring tools must also be in the calibration system.
  34. 34. A — An overspeed can overload control surfaces, flaps, panels and doors. The AMM (ATA 05) specifies the inspection; indicator accuracy may also be checked.
  35. 35. B — Halogenated agents interrupt the chemical chain reaction and are most effective on Class B and C fires; they can also be used on Class A. They leave no residue, which suits aircraft and electronics.
  36. 36. C — At least two, and preferably three, teeth should be in contact with the work. Thin material needs a fine blade (32 TPI); coarse blades (14 TPI) suit thick, soft material.
  37. 37. B — Fitting dash numbers equal the nominal tube OD in sixteenths of an inch (e.g. -8 for 1/2 in tube). Machine threads do not seal; the flare, crush washer or seal does.
  38. 38. B — Part-145 allows electronic records and work cards provided the system is adequately protected against unauthorised alteration and backed up (145.A.45(e), 145.A.55).
  39. 39. B — Gust or control locks prevent wind from slamming control surfaces against their stops, which can damage hinges, cables and structure.
  40. 40. A — Indirectly marked wire or cable should carry printed sleeves at each end and at intervals not longer than 6 ft; the individual wires inside a cable are identified within 3 in of their termination.
  41. 41. A — Glazing shows slipping and overheating; cracks show age and fatigue. The belt is replaced and the cause (tension, alignment, worn pulleys) corrected.
  42. 42. C — Whether oil is full or drained depends on how empty mass is defined for that aircraft; the manual states the required condition and any correction.
  43. 43. B — The spring is compressed (or extended) to a specified length in a spring tester and the force read. It must fall within the limits in the manual.
  44. 44. B — Damage beyond SRM limits needs approved repair data, normally from the type certificate holder or an approved design organisation, before repair.
  45. 45. C — Unsalvageable components must not re-enter the supply system unless the mandatory life limitation has been extended or a repair solution has been approved under the applicable regulation.
  46. 46. C — A detail drawing describes one part fully: size, shape, material, finish and tolerances. Assembly drawings show how parts fit together, and installation drawings show where assemblies go in the aircraft.
  47. 47. C — A joggle is a small offset formed near the edge of a part so that it can overlap another part or pass over a flange while keeping a flush contact.
  48. 48. A — Clecos come in several sizes (3/32 to 3/8 in) stamped on the fastener and colour coded for quick recognition of diameter; they hold drilled sheets in alignment before riveting.
  49. 49. A — Taper = diameter at one end - diameter at the other end of the measured length = 101.60 - 101.52 = 0.08 mm. Cylinders usually wear larger at the top, where heat and pressure are greatest.
  50. 50. B — Force must go through the tight-fitted ring; pulling through the rolling elements (e.g. via the outer ring when the inner is tight) can brinell the races. The cage must never take load.

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