BEFORE TAKEOFF CHECK-LIST

The before takeoff check is the systematic procedure

for making a check of the engine, controls, systems,

instruments, and avionics prior to flight. Normally, it is

performed after taxiing to a position near the takeoff

end of the runway. Taxiing to that position usually

allows sufficient time for the engine to warm up to at

least minimum operating temperatures. This ensures

adequate lubrication and internal engine clearances

before being operated at high power settings. Many

engines require that the oil temperature reach a

minimum value as stated in the AFM/POH before high

power is applied.

Air-cooled engines generally are closely cowled and

equipped with pressure baffles that direct the flow of

air to the engine in sufficient quantities for cooling in

flight. On the ground, however, much less air is forced

through the cowling and around the baffling.

Prolonged ground operations may cause cylinder

overheating long before there is an indication of rising

oil temperature. Cowl flaps, if available, should be set

according to the AFM/POH.

Before beginning the before takeoff check, the airplane

should be positioned clear of other aircraft. There

should not be anything behind the airplane that might

be damaged by the prop blast. To minimize

overheating during engine runup, it is recommended

that the airplane be headed as nearly as possible into

the wind. After the airplane is properly positioned for

the runup, it should be allowed to roll forward slightly

so that the nosewheel or tailwheel will be aligned fore

and aft.

During the engine runup, the surface under the airplane

should be firm (a smooth, paved, or turf surface if

possible) and free of debris. Otherwise, the propeller

may pick up pebbles, dirt, mud, sand, or other loose

objects and hurl them backwards. This damages the

propeller and may damage the tail of the airplane.

Small chips in the leading edge of the propeller form

stress risers, or lines of concentrated high stress. These

are highly undesirable and may lead to cracks and

possible propeller blade failure.

While performing the engine runup, the pilot must

divide attention inside and outside the airplane. If the

parking brake slips, or if application of the toe brakes

is inadequate for the amount of power applied, the

airplane could move forward unnoticed if attention is

fixed inside the airplane.

Each airplane has different features and equipment,

and the before takeoff checklist provided by the

airplane manufacturer or operator should be used to

perform the runup.