How often should you inspect aircraft engines?

1 Types of inspections

When inspecting your aircraft engine, the type of inspection you need to perform depends on the manufacturer's recommendations, regulations, and aircraft usage. Pre-flight inspections should be done before every flight to check for damage, leaks, corrosion, foreign objects, oil level, fuel quantity and quality, and engine instruments. Every 100 hours of flight time or 12 calendar months (whichever comes first) if using the aircraft for hire or instruction requires a more thorough 100-hour inspection. This should check for defects, wear, cracks, malfunctions, and any applicable airworthiness directives (ADs) or service bulletins (SBs). All aircraft should have an annual inspection every 12 calendar months by a certified mechanic with inspection authorization (IA). An alternative is the progressive inspection which divides the tasks into smaller segments and performs them at shorter intervals within 12 calendar months. This must follow an approved progressive inspection program that specifies the scope and frequency of each segment and personnel qualifications.

2 Inspection tips

Inspecting your aircraft engines requires following some general tips to ensure a thorough and effective job. For starters, use the manufacturer's manual and checklist as a guide, and follow the instructions and specifications for each component and system. Additionally, make sure to use the proper tools and equipment, and wear protective gear such as gloves, goggles, and earplugs. When ready, start with a cold engine and inspect it from top to bottom, in a systematic manner. Look for any abnormalities such as cracks, dents, stains, leaks, loose or missing parts, or foreign objects; listen for any unusual noises; feel for any excessive heat, vibration or resistance; and test the engine for its functionality and performance. Record your findings and actions, and keep a log of the inspection history and maintenance schedule.

3 Common issues

When inspecting aircraft engines, some of the common issues you may encounter are oil leaks, fuel leaks, spark plug fouling, and cylinder wear. Oil leaks can indicate a problem with seals, gaskets, hoses or fittings and can cause a loss of oil pressure, lubrication and cooling as well as increase the risk of fire. You should locate the source of the leak and fix or replace the faulty part as soon as possible. Fuel leaks can indicate a problem with fuel lines, pumps, filters or injectors and can cause a loss of fuel pressure, flow and quality as well as increase the risk of fire. Spark plug fouling can indicate a problem with the ignition system, fuel mixture or combustion chamber and can cause a loss of power, efficiency and smoothness as well as increase the risk of engine failure. You should check the condition and gap of the spark plugs and clean or replace them as needed. Cylinder wear can indicate a problem with piston rings, valves or cylinder walls and can cause a loss of compression, power and efficiency as well as increase the risk of oil consumption and contamination. You should check the compression and leakage of each cylinder and measure the cylinder bore and wall thickness before repairing or overhauling it if needed.

4 Signs of trouble

Inspecting your aircraft engines is an essential part of your flying routine, as it can help you detect and address any issues that may impact your flight safety and performance. When conducting an inspection, you should be on the lookout for signs of trouble such as excessive smoke, abnormal readings, engine surges, and engine vibrations. Excessive smoke can indicate a problem with the fuel mixture, oil consumption, or exhaust system; abnormal readings can point to issues with the engine instruments, sensors, or indicators; engine surges may be caused by a problem with the fuel system, ignition system, or air intake system; and engine vibrations could be due to an issue with the engine balance, alignment, or mount. By monitoring these signs and taking appropriate action when needed, you can ensure that your aircraft engines are in optimal condition.

5 Here’s what else to consider

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