Extracting unwanted air from an hydraulic system can be achieved in a number of ways. Over the years, GE has developed a compact, lightweight and highly efficient solution. This small valve can be placed virtually anywhere in the hydraulic system, expelling air by virtue of a metal ball floating upon the up-thrust of oil. This cost effective solution has stood the test of time, having been fitted to the Phantom, Buccaneer and more recently, Tornado and the latest generation Nimrod.