Engine Check / RUN-UP

Chapter 2.6

Objective

To know the correct operation for the RUN-UP

To know the functionality of engine components that are to be checked

To be able to judge whether the engine is working within its authorised limits

Performing the RUN-UP at a Parking Area

If there is enough space and the airplane is ready from a technical point of view, then the RUN-UP procedure can be performed on the parking area before taxiing. The conditions are:

• suitable temperature of the engine oil, cylinder heads and sufficient preheating
  

• enough free space behind the aeroplane

Performing the RUN-UP at a designated area

If a particular location is designated for the RUN-UP, it must used. If there is no designated area, then you may rely on experience to choose a suitable location so as not to unnecessarily block the taxiways and where no damage can occur from the propwash.

Performing the RUN-UP on a taxiway

If there is no designated area, choose a place where the rest of the traffic is not impeded:

• the prescribed distance to the active runway must be respected
  

• the approach sector must be visible

Safety measures during the RUN-UP

Due to the effect of the strong propwash during a RUN-UP, objects behind the airplane, especially other aircraft, may be damaged. By positioning the airplane at a 45 degree angle to the taxiway, in most cases this danger can be avoided. Proper positioning of the airplane avoids annoying neighbours by making minimal noise and propwash.

Consideration of Wind Conditions during the RUN-UP

With a strong wind, position the airplane into the wind. If the airplane is exposed to winds other than headwinds, this may cause improper cooling, unpleasant noises and vibrations.

Purpose of the Run-up

Verification of the correct functioning of the following engine components:

• Lubrication (Oil pressure, Oil temperature)
  

• Vacuum system (Gyro Suction)

• Magnetos (including cables and spark plugs)

• Mixture

• Carburettor Heat

Functionality of the Engine

In order to judge if the engine is functioning within its authorised limits, you must first understand how an engine works:

Four stroke engine

Carburettor

Magnetos (including cables and spark plugs)

Carburetor Heat

Lubrication (Oil pressure, Oil temperature)

Vacuum system (Gyro Suction)

Run-up

The procedure consists of a check of the engine and its associated systems.

The RUN-UP is performed in accordance to the AFM or the ENGINE OPERATORS MANUAL. If it meets the operating requirements, the following order can be used for the RUN-UP of a piston engine with a fixed-pitch propeller.

Questions

During the magneto check, you see on the left magneto a drop of 100 RPM and on the right magneto a drop of 110 RPM. What do you deduce?

• The drop in the RPM and the difference between the two magnetos are both within the tolerances. The magnetos are therefore in order.

During the Run-up you activate the carburettor heating and you notice no decrease in RPM. What do you deduce?

• The carburettor heating is not working.