PSA Airlines Canadair Regional Jet Systems (PSA-CRJ) Practice Exam

Does the APU bleed air duct contain a one-way check valve to prevent engine bleed air backup?

1. True

2. False

3. Only in emergencies

4. True, but only for older models

The correct answer is: True

The correct answer is that the APU bleed air duct indeed contains a one-way check valve designed to prevent engine bleed air from backing up into the APU. This one-way check valve is critical for maintaining the proper function of the Auxiliary Power Unit (APU) and ensuring safety and reliability. In the context of the APU's role, it provides bleed air that is necessary for various aircraft functions, such as air conditioning and engine start. If there were a backup of engine bleed air into the APU system, it could lead to potential performance issues, including overheating and damage to the APU. The inclusion of a check valve is therefore a vital part of the design, ensuring that airflow is directed correctly and that the systems can function independently without interference from each other. This design applies to all models and is a standard feature rather than something limited to older models or specific situations such as emergencies. Thus, confirming the presence of this check valve within the system highlights its importance in maintaining the integrity of both the APU and the overall aircraft operations.