GB576143A - Fuel jettison apparatus - Google Patents

Abstract

576,143. Siphons. FLIGHT REFUELLING, Ltd., and LEGGE, C. N. March 10, 1944, No. 4523. [Class 69 (i)] A siphon, more particularly for apparatus for enabling the whole or part of the fuel in an aircraft tank to be jettisoned, is controlled by apparatus in which a charge of compressed air or gas is arranged to be discharged so that while the siphon is being filled with liquid the pressure of the charge maintains a closure of the siphon outlet until, due to continued discharge, the pressure has fallen below a predetermined value. The siphon 17 has its inlet controlled by a valve 26 normally held closed by a spring 28, and its outlet controlled by a valve 20 normally held open by a spring 21. A charge of compressed air is admitted to a container 1 through valve 4, pipe 3 and valve 29 pressed upwardly by spring 30, pipe 2 being then open to atmosphere. When fuel is to be jettisoned, the valve 4 is moved to open the pipe 3 to atmosphere so that valve 29 is closed, and to open the pipe 2 to the air supply ; air then passes through pipe 22 to act on piston 24 and open the siphon inlet valve 26, and also passes through pipe 2 to act on piston 7 and open a spring-pressed valve 9, whereupon air from the container 1 flows through pipe 11 to depress a piston 18 and close the siphon outlet valve 20, the air then passing through pipe 13 to an ejector nozzle 14 to withdraw air from the siphon through pipe 16, the siphon thus being filled with fuel. When ' the pressure in the container 1 falls sufficiently, the valve 29 opens, the'remaining pressure is dispersed rapidly and the outlet valve 20 opens to allow the fuel to be jettisoned. The flow may be stopped by moving valve 4 to admit a fresh charge to the container 1, the valve 26 then closing. Hammer from the liquid may be prevented by providing one or more ball and spring or other relief valves near the valve 20, or by means for slowing the closure of said valve..