A&P Cheat Sheet 2026

The 30 highest-yield A&P facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. Jet-A turbine engine fuel appears what color in its natural state? → Clear to straw-colored
2. Which tool would you use to measure the inside diameter of a cylinder bore? → Telescoping gauge
3. Which type of engine is commonly used in modern commercial airliners? → High-bypass turbofan engine
4. What is the purpose of the oil system in an aircraft engine? → To lubricate, cool, and clean engine components.
5. What is the primary purpose of a crossfeed fuel system in a multi-engine aircraft? → To allow any engine to draw fuel from any tank on the aircraft
6. An aircraft with a total weight of 2,100 pounds has a total moment of 96,600 in-lb. What is the location of its Center of Gravity (CG)? → 46.0 inches aft of datum
7. According to AC 43.13-1B, when routing electrical wiring, what is the maximum interval between support clamps for a wire bundle? → 24 inches
8. What action must a mechanic take if they find an unairworthy condition during an inspection? → Record the discrepancy and prevent the aircraft from being used until repaired
9. What is the minimum age requirement to obtain an FAA A&P certificate? → 18 years
10. What is the function of the fuel selector valve in an aircraft fuel system? → To select which fuel tank supplies fuel to the engine
11. Which FAA regulation part specifies the requirements for obtaining an A&P mechanic certificate? → 14 CFR Part 65
12. Which type of fuel is used in turbine (jet) engines? → Jet-A or Jet-A1 kerosene-based fuel
13. According to 14 CFR Part 43, Appendix D, which of the following is an action required of a mechanic before beginning an annual or 100-hour inspection? → Remove or open all necessary inspection plates, access doors, fairings, and cowling.
14. Which FAA document must be completed after performing a major repair? → FAA Form 337
15. What is the primary purpose of an airframe in an aircraft? → To provide structural support and aerodynamic surfaces.
16. Which inspection method is used to detect cracks in airframe components without disassembly? → Dye penetrant inspection.
17. Which of the following statements is true regarding the installation of piston rings on a piston during a reciprocating engine overhaul? → Ring gaps should be staggered around the piston to prevent excessive blow-by.
18. Which component of a turbine engine compresses incoming air before combustion? → Compressor
19. What is the primary purpose of a fuel strainer (gascolator) in an aircraft fuel system? → To remove water and sediment from the fuel
20. Which FAA regulation specifies certification requirements for A&P mechanics? → 14 CFR Part 65
21. What is the minimum age requirement to obtain an FAA A&P mechanic certificate? → 18 years
22. What color is 100LL aviation gasoline? → Blue
23. In a gas turbine engine, what is the primary function of the diffuser section located between the compressor and the combustor? → To decrease the velocity and increase the static pressure of the air.
24. Under FAR Part 43, the aircraft fuel system is inspected as part of which required inspection interval? → Every 100 hours as part of the 100-hour inspection
25. Which material is commonly used in modern airframe construction due to its high strength-to-weight ratio? → Carbon fiber reinforced polymer (CFRP)
26. Which airframe component is responsible for controlling roll during flight? → Ailerons
27. What is the purpose of the APU (Auxiliary Power Unit) in an aircraft? → To provide power for ground operations and engine start.
28. Which of the following is a primary advantage of an alternator over a generator in a light aircraft electrical system? → Alternators are lighter and produce more stable voltage at low engine RPMs.
29. Which of the following is a critical maintenance step for pneumatic de-icing boots to ensure their longevity and proper operation? → Regularly cleaning them with approved agents and applying a rubber preservative.
30. What is an integral fuel tank? → A portion of the aircraft structure that has been sealed to contain fuel