Differential pressure between ambient air and the fuel tank can result in damage. The aircraft’s climb into thin air or descent (dive) into higher atmospheric pressure leads to such a differential pressure. A climb and dive valve equalizes those pressures and relieves those stresses.

The climb and dive valve (CDV) is a hydro-mechanical multi-functioning device consisting of two separate positive and negative pressure-regulating and relief modules integrated into a single device that controls tank pressure during all operational conditions, including climb and dive. The CDV is either installed inline or surface mounted at the surge bay tank.

During conditions that create a positive delta pressure between the aircraft fuel tank and the environment, the positive pressure-regulating module will actuate into the open position and allow air flow from the surge tank into the atmosphere. This prevents over-pressurization of the aircraft surge and main tanks.

During conditions that create a negative delta pressure between the aircraft surge tank and the environment, the negative pressure regulating valve will actuate into the open position and allow air flow from the exterior of the aircraft into the surge tank. This also prevents over-pressurization of the aircraft.

APPLICATIONS:  
This technology has been used primarily on military aircraft outfitted with a closed vent system. Several climb and dive valve (CDV) configurations are designed and manufactured by the Parker Aerospace’s Fluid Systems Division (FSD). These valve systems are qualified on aircraft such as F15, F16, C-17, F-35, A400M, and KC-46.

FEATURES AND ATTRIBUTES:  
•    Reduces differential pressure between atmospheric pressure and internal fuel tank pressure
•    Reduces aircraft weight by minimizing number of air separation modules while keeping all fuel tanks inerted
•    Capable to inward and outward flows from 2 to 70 PPM (size dependent)

OPTIONAL FEATURES:
•    Installed in-line with the aircraft vent line or surface mounted at the surge bay tank
•    Compliance with either conducted/direct lightning strike
•    Compliance with 2000˚F fire test
•    Service media: Air, nitrogen-enriched air (NEA), jet fuels (jet A, A1, etc.)