Certified Flyers II
Duchess Multi-Engine Study Guide
14
The Duchess is equipped with two engine-driven, dry, pressure pumps interconnected to form a
single system. If either pump fails, check valves will automatically close and the remaining
pump will continue to operate all gyro instruments. A pressure gauge is located on the pilot’s
subpanel and a no gyro annunciator light indicates loss of a pressure pump. The operational
limits are 4.8-5.2 in of mercury.
Section 3: