What should a pilot do upon observing dripping nozzles while the aircraft is parked and turned off?

When a pilot observes dripping nozzles while the aircraft is parked and turned off, checking the condition of the check valve is a critical step. The check valve is designed to prevent the backflow of chemicals that could lead to leakage from the nozzles when the aircraft is not in operation. If the nozzles are dripping, it often indicates that the check valve may be faulty or not sealing properly, allowing liquid to escape even when the system is not pressurized.

By inspecting the check valve, the pilot can determine whether it is functioning correctly or if it needs maintenance or replacement. Addressing issues with the check valve is essential for ensuring the overall integrity and safety of the application system, as it directly influences the proper functioning of the nozzles during aerial application operations.