Wing tanks are vented to the atmosphere as well as each other through vent lines which provide vacuum and pressure relief for the tanks.

The statement is accurate because wing tanks in aircraft are designed with venting systems that allow for the equalization of pressure and to prevent the formation of vacuum or excessive pressure within the tanks. Each tank is vented to the atmosphere as well as to adjacent tanks through vent lines. This design serves multiple purposes: it enables fuel to flow smoothly from the tank to the engines without restriction caused by pressure changes, and it helps to avoid structural damage to the tanks that might occur from vacuum or pressure buildup.

When fuel is drawn from the tank, the volume decreases, which could create a vacuum. The vent lines allow air to enter the tank, balancing the pressure. Conversely, if fuel expands due to temperature increase or jettisoning, the vents allow the excess pressure to escape. Overall, this venting system is crucial for maintaining safe and efficient operation of the fuel system in the aircraft.