Airbus A320 Auxiliary Power Unit (APU) start

Summary

This video provides a detailed guide on starting the Airbus A320's Auxiliary Power Unit (APU). It emphasizes the importance of checking aircraft systems, ensuring sufficient fuel, and monitoring critical indicators such as RPM and EGT. The presenter outlines the necessary steps, including powering on batteries and checking for fault messages, while also advising viewers to adhere to safety precautions. With clear instructions and a focus on good practices, this tutorial serves as a valuable resource for understanding the APU startup process in an aircraft environment.

Takeaways

• 🔌 Ensure that the aircraft's auxiliary power unit (APU) is off before starting the sequence.
• ✅ Perform a general check of the aircraft systems before initiating the APU start.
• ⚠️ This video is for illustrative purposes only; always refer to approved maintenance documents.
• 🔋 Check that the aircraft batteries are on and functioning properly before starting the APU.
• ⛽ Ensure there is enough fuel available to run the APU.
• 🚪 Wait for the 'flip open' message to confirm the APU inlet door is open, although it's not mandatory.
• ⚙️ The APU start switch should be turned on to initiate the starting process.
• 📈 Monitor the RPM and EGT (Exhaust Gas Temperature) during the APU start for safety.
• 🌬️ The APU becomes available for pneumatic power once the EGT rises and the system stabilizes.
• ⚡ Transition from external power to the APU generator to provide electrical power once the APU is running.

Q & A

What is the purpose of the Airbus A320 auxiliary power unit (APU)?

The APU is used to provide electrical power and pneumatic air to the aircraft when the main engines are not running, particularly during ground operations.

Why is it important to ensure the APU is off before starting the sequence?

The APU must be off to prevent any faults during the startup procedure and to ensure safety.

What should be checked before starting the APU?

Before starting the APU, one should check the batteries, fuel levels, and ensure there are no fault messages related to the APU.

Why is it crucial to have the batteries on during APU operation?

The batteries must be on at all times when the APU is running to ensure the fire extinguishing system is operational.

What does the 'flip open' message indicate during APU startup?

The 'flip open' message indicates that the APU inlet door is open, which is important for the startup process.

What should be monitored during the APU startup process?

During APU startup, it is important to monitor the engine temperature (EGT) and RPM to ensure they remain within safe limits.

What happens when the APU reaches approximately 65 RPM?

When the APU reaches approximately 65 RPM, the engine control box (ECB) will remove power from the APU structure, allowing it to accelerate on its own.

What does the APU available message signify?

The APU available message indicates that the APU is now ready to provide electrical or pneumatic power.

What should be done after the APU is confirmed available?

After the APU is available, the APU bleed valve can be turned on to provide pneumatic power for air conditioning and engine starting.

What is the final precaution mentioned before using the APU?

The final precaution is to pay attention to all safety measures and follow approved maintenance documents.