Which equipment must not be operated while hydraulic system tubing is disconnected?

The Ground Maintenance Motor Pump is specifically designed to pressurize the hydraulic system for testing and maintenance purposes. However, when the hydraulic system tubing is disconnected, operating the motor pump can lead to several issues.

When the system is disconnected, the hydraulic fluid cannot be contained within the intended pathways, which can cause leaks and potentially damage the pump or other components due to the lack of proper hydraulic pressure. Additionally, operating the pump without a complete system can result in air being introduced into the hydraulic lines, which compromises system integrity and may lead to ineffective operation or failure when the system is reconnected.

Understanding the function and risks associated with the Ground Maintenance Motor Pump highlights its critical role in the overall maintenance and safety of the hydraulic system in the F-35. Hence, the prohibition against operating it while the hydraulic system tubing is disconnected is necessary to prevent damage and ensure safety during maintenance procedures.