Free CAAS SAR-66 Module 17 — Propeller (Category B1.1) Practice Questions

Sample Practice Questions

Try these 10 sample questions from the CAAS SAR-66 Module 17 — Propeller (Category B1.1) practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1What energy conversion is performed by an aircraft propeller?

   1. A.Rotary shaft power into propulsive thrustCorrect answer: A
   2. B.Propulsive thrust into combustion heat
   3. C.Combustion heat into electrical power
   4. D.Electrical power into exhaust pressure

   Explanation: The FAA handbook states: "the propeller transforms the rotary power of the engine into thrust." The propeller receives mechanical rotation from the engine and produces thrust. The other choices describe different energy paths, rather than the propeller's function.

   Reference: FAA Aviation Maintenance Technician Handbook — Powerplant, Chapter 7 — Chapter 7, p. 7-2

2. 2How are blade stations commonly located when analysing a propeller blade?

   1. A.By angular displacement from the feather stop
   2. B.By distance from the centre of the hubCorrect answer: B
   3. C.By distance aft of the engine firewall
   4. D.By the number of laminations in the blade

   Explanation: The FAA handbook states: "station numbers in inches from the center of the blade hub." A station is a radial distance referenced to hub centre, not a pitch angle, an aircraft longitudinal datum, or a material-layer count.

   Reference: FAA Aviation Maintenance Technician Handbook — Powerplant, Chapter 7 — Chapter 7, p. 7-3

3. 3Which governor component does the cockpit propeller control adjust to select the governed rpm?

   1. A.The blade-root bearing preload
   2. B.The governor speeder-spring tensionCorrect answer: B
   3. C.The propeller mounting-flange clearance
   4. D.The slip-ring brush contact pressure

   Explanation: The FAA handbook states: "compresses or releases the governor speeder spring." The cockpit control changes the speed reference through speeder-spring tension. Blade mounting, brush pressure and flange clearance are unrelated adjustments, not governor rpm selection.

   Reference: FAA Aviation Maintenance Technician Handbook — Powerplant, Chapter 7 — Chapter 7, p. 7-8

4. 4What additional control does synchrophasing provide beyond matching propeller rpm?

   1. A.Maintaining a selected angular relationship between bladesCorrect answer: A
   2. B.Maintaining an identical oil pressure in both governors
   3. C.Maintaining the same fuel flow in both engines
   4. D.Maintaining identical blade tracking tolerances

   Explanation: The source states: "maintain a preset angular relationship between the designated master propeller and the slave propellers." Synchrophasing controls relative blade phase as well as speed. Equal oil pressures, fuel flows and tracking tolerances are not the additional controlled variable.

   Reference: FAA Aviation Maintenance Technician Handbook — Powerplant, Chapter 7 — Chapter 7, p. 7-19

5. 5Which icing effect can directly create a propeller mass imbalance?

   1. A.Equal ice mass at equal radii on every blade
   2. B.An equal temperature decrease across all blades
   3. C.An equal increase in drag on every blade
   4. D.Unequal ice accumulation on different bladesCorrect answer: D

   Explanation: The FAA handbook states: "ice collects asymmetrically on a propeller blade and produces propeller unbalance and destructive vibration" Unequal deposited ice mass can unbalance the rotating assembly. Equal mass at equal radii does not create the stated inequality; equal temperature or drag changes are not unequal added mass.

   Reference: FAA Aviation Maintenance Technician Handbook — Powerplant, Chapter 7 — Chapter 7, p. 7-17

6. 6A metal propeller blade has a sharp nick that appears small. Why does it still require prompt assessment and an approved repair decision?

   1. A.The sharp notch relieves local stress and slows fatigue growth
   2. B.The small loss of mass affects balance without affecting fatigue
   3. C.The sharp notch concentrates stress and can initiate fatigue failureCorrect answer: C
   4. D.The small notch changes surface appearance without structural effect

   Explanation: The handbook warns of "fatigue failure resulting from the concentration of stresses at the bottoms of sharp nicks, cuts, and scratches." C explains why even a small sharp defect warrants assessment. A reverses the stress-concentration effect; B overlooks fatigue by considering only lost mass; D mistakes small size for harmless cosmetic damage. Repair decisions must follow the applicable instructions.

   Reference: FAA Aviation Maintenance Technician Handbook — Powerplant, Chapter 7 — Chapter 7, p. 7-21

7. 7A Hartzell propeller has already entered its calendar overhaul interval. It is then removed and stored. What happens to that calendar interval under Manual 115N?

   1. A.It continues despite removal and storageCorrect answer: A
   2. B.It restarts when the propeller is reinstalled
   3. C.It pauses until the storage packaging is opened
   4. D.It becomes a flight-hour-only limit during storage

   Explanation: The manufacturer states: "The calendar limit is not interrupted by subsequent removal and/or storage." Storage does not stop a calendar interval that has begun. Restarting or pausing it, or converting it to a flight-hour-only interval, would misapply the manufacturer's rule.

   Reference: Hartzell Propeller Owner's Manual 115N — Introduction §8.A(5), p.1-9

8. 8A propeller has a geometric pitch of 80 inches and advances 68 inches during one revolution. What is its slip for that revolution?

   1. A.148 inches
   2. B.12 inchesCorrect answer: B
   3. C.68 inches
   4. D.80 inches

   Explanation: The FAA handbook states: "Geometric pitch - Effective pitch = slip" Slip = 80 − 68 = 12 inches per revolution. Adding the pitches gives 148; 68 is effective pitch, while 80 is geometric pitch. Neither individual pitch is the difference.

   Reference: FAA Aviation Maintenance Technician Handbook — Powerplant, Chapter 7 — Chapter 7, p. 7-2

9. 9Which part of a propeller blade is its thick, rounded portion near the hub?

   1. A.The blade tip
   2. B.The blade face
   3. C.The blade shankCorrect answer: C
   4. D.The leading edge

   Explanation: The FAA handbook states: "The blade shank is the thick, rounded portion of the propeller blade near the hub" The shank provides strength near the hub. The tip is outboard, the face is an airfoil surface, and the leading edge meets the air first.

   Reference: FAA Aviation Maintenance Technician Handbook — Powerplant, Chapter 7 — Chapter 7, p. 7-3

10. 10An engine-driven governor senses an overspeed. How do its flyweights initially respond?

    1. A.They tilt inward and lower the pilot valve
    2. B.They remain centred and close the oil inlet
    3. C.They tilt outward and raise the pilot valveCorrect answer: C
    4. D.They stop rotating and release the speeder spring

    Explanation: The FAA handbook states: "The flyweights tilt outward and raise the pilot valve." In overspeed, centrifugal force exceeds speeder-spring force. Inward movement belongs to underspeed, balance describes on-speed, and the flyweights do not stop to sense the condition.

    Reference: FAA Aviation Maintenance Technician Handbook — Powerplant, Chapter 7 — Chapter 7, p. 7-11