How to Performing a Preflight Check on a Cessna 172

Gather required aircraft paperwork and current weather data before beginning physical inspection of the aircraft. Example: Verify aircraft registration, airworthiness certificate, operating handbook, and weight & balance data are current and aboard aircraft, check aircraft maintenance logbooks for any open discrepancies, required inspections, or airworthiness directives that might ground the aircraft, obtain current weather briefing including surface conditions, winds aloft, NOTAMs, and forecast for departure and destination airports, review flight plan routing and calculate fuel requirements based on current weather conditions and aircraft performance data, check runway conditions and any temporary closures that might affect departure or arrival operations, verify personal documents including pilot certificate, medical certificate, and current flight review or instrument proficiency check as required, confirm aircraft insurance is current and covers planned flight operation, and review any special flight restrictions or temporary flight restrictions along planned route of flight.

Systematically inspect aircraft exterior starting from cockpit and working clockwise around entire aircraft checking for damage, security, and proper configuration. Example: Begin at pilot door checking for proper closure and security of door latches, examine cockpit windows for cracks, scratches, or other damage that could affect visibility, inspect left wing from root to tip checking wing skin for dents, scratches, corrosion, or loose rivets, examine left aileron for full and free movement, proper rigging, and secure attachment to wing structure, check left main landing gear for proper tire inflation, brake disc condition, gear leg security, and any signs of hydraulic leaks, continue around nose section inspecting propeller for nicks, cracks, or other damage while ensuring propeller is secure on crankshaft, examine nose gear for proper extension, tire condition, steering linkage security, and shock strut inflation, inspect right side of aircraft using same systematic approach as left side ensuring all components are secure and undamaged, and use flashlight for detailed inspection of areas in shadow or low light conditions.

Open engine cowling and inspect engine, accessories, and fluid levels for proper condition and serviceability. Example: Remove cowling fasteners and carefully lift cowling sections to access engine compartment, visually inspect engine for any obvious leaks, loose connections, or damaged components, check all visible hoses and clamps for security, cracking, or deterioration that could lead to failure, examine exhaust system for cracks, loose connections, or carbon deposits that might indicate internal engine problems, locate and remove engine oil dipstick, clean dipstick thoroughly and reinsert fully before removing again to get accurate oil level reading, verify oil level is between minimum and maximum marks on dipstick - typical Cessna 172 requires 6-8 quarts depending on engine model, check oil color and consistency for signs of contamination or excessive metal content that might indicate engine wear, inspect engine accessories including alternator, vacuum pump, and magnetos for security and proper belt tension, examine air filter for cleanliness and proper installation, and replace cowling ensuring all fasteners are properly secured.

Draw fuel samples from all sump points and visually inspect for contamination while verifying adequate fuel quantity for planned flight. Example: Locate all fuel sump drain points - typically 3 per wing plus gascolator sump for total of 7 drain points on most Cessna 172 models, use fuel tester to draw sample from each sump point starting with lowest points and working upward, visually inspect each fuel sample for water contamination (appears as clear bubbles or separate layer at bottom), sediment, or wrong fuel type, test fuel sample by comparing color to known good 100LL fuel - should be blue color and proper consistency, dispose of contaminated fuel samples properly or return clean fuel to tank using fuel tester's return feature, check fuel quantity by visual inspection of tank levels through fuel caps or using fuel quantity gauges if aircraft is so equipped, calculate total fuel on board and verify adequate quantity for planned flight plus required reserves, check fuel caps for proper sealing and security to prevent contamination or fuel loss during flight, examine fuel vents for blockage that could cause tank collapse or improper fuel flow, and document any fuel quality issues in aircraft discrepancy log.

Check all primary and secondary flight controls for proper operation, security, and full range of motion without binding. Example: Remove control locks if installed and ensure controls move freely throughout full range of travel, check ailerons for proper up and down movement with coordinated operation between left and right sides, inspect aileron hinges, control rods, and bellcranks for security, wear, or damage, examine elevator for full up and down travel while checking trim tab for proper rigging and security, verify rudder moves fully left and right with proper coordination between rudder pedals and rudder surface movement, inspect elevator trim wheel or electric trim for proper operation and verify trim indicator shows neutral or appropriate setting, check flap operation through full range of travel noting any binding, unusual noise, or asymmetric operation between left and right flaps, examine all control surface attach points including hinges, brackets, and control cables for security and proper tension, verify all cotter pins, safety wire, and other locking devices are properly installed, and ensure no tools, rags, or other items are left in control surface areas that could interfere with operation.

Inspect pitot tube, static ports, and avionics equipment for proper condition and configuration before flight. Example: Remove pitot cover if installed and inspect pitot tube opening for blockage by insects, ice, or other debris, check pitot tube mounting for security and examine heating element if aircraft is equipped with pitot heat, locate static ports on fuselage sides and verify they are clear of obstructions and properly sealed, examine antennas for security, proper mounting, and absence of damage that could affect radio performance, check navigation lights and strobes for proper operation and bulb condition, test landing light operation and inspect lens for cracks or moisture intrusion, verify beacon and taxi lights function properly and switches operate correctly, inspect avionics cooling vents for blockage that could cause equipment overheating, check external power receptacle if installed for proper cover installation and security, examine tie-down points and securing hardware for damage or wear, and install pitot cover after inspection to prevent contamination during ground operations.

Complete interior inspection and systems verification to ensure aircraft is ready for safe flight operations. Example: Enter aircraft and adjust seat position and seat belts for proper pilot positioning and comfort during flight, check all interior lights including dome light, instrument lighting, and emergency lighting for proper operation, verify all required documents are aboard including registration, airworthiness certificate, operating handbook, and weight & balance data, test flight controls from pilot seat ensuring full and free movement in all directions without binding or unusual resistance, check instrument panel for proper readings on all gauges and verify no warning lights are illuminated, test radios, transponder, and navigation equipment for proper operation and appropriate frequency settings, verify fuel selector valve is in proper position for flight operations and moves freely to all positions, check mixture control, propeller control, and throttle for smooth operation throughout full range of travel, test magneto switch operation and verify ignition system is properly grounded when switch is in OFF position, and complete engine start checklist to verify all systems are ready for engine operation.

Conduct final walk-around inspection and document preflight completion before beginning flight operations. Example: Perform final walk-around inspection to verify all cowling fasteners, inspection plates, and access panels are properly secured, check that all ground equipment including wheel chocks, tie-downs, and external power sources are removed from aircraft, verify propeller area is clear of personnel and debris before engine start, ensure all baggage and equipment is properly secured in baggage compartment and does not exceed weight or center of gravity limitations, remove wing covers or other protective equipment if installed and store properly, complete preflight inspection checklist and make appropriate logbook entry documenting inspection results, brief passengers on safety procedures including seat belt use, door operation, emergency exits, and emergency equipment locations, set radios to appropriate frequencies for ground operations and verify transponder is set to standby mode, position aircraft controls and systems for engine start per aircraft operating handbook procedures, and verify weather conditions remain suitable for planned flight operations before proceeding with engine start.