What is the purpose of monitoring engine instruments during start?

• A. To monitor only fuel quantity.
• B. To ensure start sequence is completed without any check on engine parameters.
• C. To verify cabin pressure.
• D. To confirm that engine parameters such as EGT, N1/N2 rise appropriately and oil pressure stabilizes without abnormal indications.

Answer: (D)

During start, you watch engine instruments to confirm the engine is bringing itself up to speed safely and that no abnormal conditions are developing. The main indicators are how the exhaust gas temperature (EGT) behaves, how the rotor speeds (N1/N2) rise, and how the oil pressure responds. EGT should climb in a controlled, expected manner as fuel is introduced and ignition occurs, then stabilize as the engine reaches a stable operating state. N1 and N2 should ramp up to the appropriate start or idle speeds, showing the turbine is spooling correctly. Oil pressure should quickly rise to a normal value and stay stable, indicating the lubrication system is pressurized and functioning.

If these parameters behave as expected—EGT rising gradually and stabilizing, N1/N2 increasing properly, and oil pressure coming up without delay or abnormal fluctuations—the start can proceed normally. If any of these indicators show abnormal indications, such as excessively high EGT, no or delayed rise in oil pressure, or incorrect rotor speeds, it signals a potential problem that needs attention before advancing with the start or accepting a running engine.

The other options miss essential aspects of what’s being monitored during start or refer to unrelated systems, which is why they’re not correct.