Which of the following influences the operation of an automatic fuel control unit on a turbojet engine?

The operation of an automatic fuel control unit on a turbojet engine is primarily influenced by burner pressure. This is because the fuel control unit needs to ensure that the correct amount of fuel is supplied to maintain optimal combustion conditions within the combustor. The burner pressure reflects the conditions in the combustion chamber, which directly affects the engine's performance and efficiency. By monitoring burner pressure, the automatic fuel control unit can adjust fuel flow accordingly to achieve the desired thrust and maintain stable operation, especially during variations in engine speed and load conditions.

While oil temperature, exhaust gas temperature, and ambient air pressure are important parameters in the overall operation of the engine, they do not directly control the fuel flow in the same way that burner pressure does. The fuel control unit is specifically designed to respond to combustion conditions, making burner pressure a critical factor in ensuring safe and efficient engine operation.