Which statement about hydraulic system is true?

Which statement about hydraulic system is true?

• A. The normal hydraulic tank quantity is 45-85%
• B. The normal hydraulic tank quantity is 0-25%
• C. The normal hydraulic tank quantity is 60-90%
• D. The normal hydraulic tank quantity is 90-100%

Answer: (A)

Maintaining the hydraulic reservoir within a defined normal range ensures there is enough fluid for pumps to operate and room for thermal expansion. In this aircraft, the normal hydraulic tank quantity is about 45 to 85 percent. This range provides a buffer for fluid expansion with heat and still leaves enough fluid for peak demand, avoiding pump cavitation or loss of hydraulic power. Values well below that range indicate low fluid and risk of pump problems, while higher values approaching the upper limit leave little room for expansion and could lead to overflow. So, 45–85 percent is the true normal range.

Maintaining the hydraulic reservoir within a defined normal range ensures there is enough fluid for pumps to operate and room for thermal expansion. In this aircraft, the normal hydraulic tank quantity is about 45 to 85 percent. This range provides a buffer for fluid expansion with heat and still leaves enough fluid for peak demand, avoiding pump cavitation or loss of hydraulic power. Values well below that range indicate low fluid and risk of pump problems, while higher values approaching the upper limit leave little room for expansion and could lead to overflow. So, 45–85 percent is the true normal range.