Airworthiness Manual Chapter 522 Subchapter H - Engines - Canadian Aviation Regulations (CARs)

Content last revised: 2012/06/01


  • A (522.1-522.3)
  • B (522.21-522.255)
  • C (522.301-522.597)
  • D (522.601-522.885)
  • E (522.901-522.1193)
  • F (522.1301-522.1449)
  • G (522.1501-523.1589)
  • H (522.1801-523.1857)
  • J (522.1901-523.1947)


F, G, I, J, K


Subchapter H - Engines


522.1801 Applicability

This Subchapter H is applicable to spark-and-compression-ignition engines for powered gliders.
(amended 2007/07/16)

522.1805 Instruction Manual

An instruction manual containing the information that the applicant considers essential for installing, operating, servicing and maintaining the engine must be provided.

522.1807 Engine Ratings and Operating Limitations

Engine ratings and operating limitations to be established are based on the operating conditions demonstrated during the bench tests prescribed in this Subchapter H. They include power ratings and operational limitations relating to speeds, temperatures, pressures, fuels and oils which the applicant finds necessary for the safe operation of the engine.

522.1808 Selection of Engine Power Ratings

Each selected rating must be for the lowest power that all engines of the same type may be expected to produce under the conditions to determine that rating.

Design and Construction

522.1815 Materials

The suitability and durability of materials used in the engine must -

  • (a) Be established on the basis of experience or tests; and

  • (b) Conform to approved specifications that ensure their having the strength and other properties assumed in the design data.

522.1817 Fire Prevention

  • (a) The design and construction of the engine and the materials used must minimize the probability of the occurrence and spread of fire because of structural failure, overheating or other causes.

  • (b) Each external line or fitting that conveys flammable fluids must be at least fire resistant. Components must be shielded or located to safeguard against the ignition of leaking flammable fluid.

522.1819 Durability

Engine design and construction must minimize the probability of occurrence of an unsafe condition of the engine between overhauls.

522.1821 Engine Cooling

Engine design and construction must provide the necessary cooling under conditions in which the powered glider is expected to operate.

522.1823 Engine Mounting Attachments and Structure

  • (a) The maximum allowable loads for engine mounting attachments and related structure must be specified by the applicant.

  • (b) The engine mounting attachments and related structure must be able to withstand the specified loads without failure, malfunction or permanent deformation.

522.1825 Accessory Attachment

Each accessory drive and mounting attachment must be designed and constructed so that the engine will operate properly with the accessories attached. The design of the engine must allow the examination, adjustment or removal of each essential engine accessory.

522.1833 Vibration

The engine must be designed and constructed to function throughout its normal operating range of crankshaft rotational speeds and engine powers without inducing excessive stress in any of the engine parts because of vibration and without imparting excessive vibration forces to the structure of the powered glider.

522.1835 Fuel and Induction System

  • (a) The fuel system of the engine must be designed and constructed to supply the appropriate mixture of fuel to the combustion chambers throughout the complete operating range of the engine under all starting, flight and atmospheric conditions.

  • (b) The intake passages of the engine through which air, or fuel in combination with air, passes must be designed and constructed to minimize ice accretion and vapour condensation in those passages. The engine must be designed and constructed to permit the use of a means for ice prevention.

  • (c) The type and degree of fuel filtering necessary for protection of the engine fuel system against foreign particles in the fuel must be specified. The applicant must show (e.g. within the 50-hour run prescribed in 522.1849(a)) that foreign particles passing through the prescribed filtering means will not critically impair engine fuel system functioning.

  • (d) Each passage in the induction system that conducts a mixture of fuel and air, and in which fuel may accumulate, must be self-draining to prevent a liquid lock in the combustion chambers. This applies to all attitudes that the applicant establishes as those the engine can have when the powered glider in which it is installed is in the static ground attitude.

522.1839 Lubrication System (Four-stroke Engines Only)

  • (a) The lubrication system of the engine must be designed and constructed so that it will function properly in all attitudes and atmospheric conditions in which the powered glider is expected to operate. In wet-sump engines this requirement must be met when the engine contains only the minimum oil quantity, the minimum quantity being not more than half the maximum quantity.

  • (b) The lubrication system of the engine must be designed and constructed to allow installing a means of cooling the lubricant.

  • (c) The crankcase must be vented to preclude leakage of oil from excessive pressure in the crankcase.

Bench Tests

522.1843 Vibration Test

Except where the engine is of a type of construction known not to be prone to hazardous vibration, the engine must undergo a vibration survey to establish crankshaft torsional and bending characteristics over a range of rotational speeds from idling to 110% of the maximum continuous speed or 103% of the maximum desired take-off speed, whichever is the greater. The survey must be conducted with a representative propeller. No hazardous condition may be present.

522.1845 Calibration Test

Each engine must be subjected to the calibration tests necessary to establish its power characteristics and the conditions for the endurance test specified in 522.1849(a) to (c). The results of the power characteristics calibration tests form the basis for establishing the characteristics of the engine over its entire operating range of crank shaft rotational speeds, manifold pressures, and fuel/air mixture settings. Power ratings are based on standard atmospheric conditions at sea-level.

522.1847 Detonation Test (Spark Ignition Only)

The engine must be tested to establish that it can function without detonation throughout the range of intended conditions of operation.

522.1849 Endurance Test


  • (a) The engine must be subjected to an endurance test (with a representative propeller) that includes a total of 50 hours of operation and consists of the cycles specified in 522.1849(c).

  • (b) Additional endurance testing at particular rotational speed(s) may be required depending on the results of the tests prescribed in 522.1843, to establish the ability of the engine to operate without fatigue failure.

  • (c) Each cycle must be conducted as follows:

    Sequence Duration
    Operating Conditions
    Starting - idle
    Take-off power
    Cooling run (Idle)
    Take-off power
    Cooling run (Idle)
    Take-off power
    Cooling run (Idle)
    75% of maximum continuous power
    Cooling run (Idle)
    Maximum continuous power
    Cooling run and stop
    Total 120 n/a not applicable
  • (d) During or following the endurance test the fuel and oil consumption must be determined.


522.1851 Operation Test

The operation test must include the demonstration of backfire characteristics, starting, idling, acceleration, overspeeding and any other operational characteristics of the engine.

522.1853 Engine Component Test

  • (a) For engine components that cannot be adequately substantiated by endurance testing in accordance with 522.1849(a) to (c), the applicant must conduct additional tests to establish that components are able to function reliably in all normally anticipated flight and atmospheric conditions.

  • (b) Temperature limits must be established for each component that requires temperature controlling provisions to ensure satisfactory functioning, reliability and durability.

522.1855 Teardown Inspection

After the endurance test has been completed the engine must be completely disassembled. No essential component may show rupture, cracks or excessive wear.

522.1857 Engine Adjustment and Parts Replacement

Service and minor repairs to the engine may be made during the bench tests. If major repairs or replacements of parts is necessary during the tests or after the teardown inspection, or if essential parts have to be replaced, the engine must be subjected to any additional tests the Minister may require.
(amended 2007/07/16)