FIELD: aircraft, hydraulic, fuel and oil systems. SUBSTANCE: bypass valve has bush and spring-loaded spool valve; their shut-off surfaces and throttling edges are separated. Cavity located between shut-off surfaces and throttling edges and cavity discharging liquid from valve are connected with sensor or with pressure differential indicator giving signal for opening. Indicator is adjusted to pressure differential lesser than that of valve opening. EFFECT: enhanced operational reliability of hydraulic systems (fuel and oil systems inclusive). 1 dwg
