The dynamics of a pressure-regulating valve of an aircraft hydraulic system has been solved analytically. It has been shown that there exist conditions under which the dynamic response parameters of a linear lumped subsystem of fourth order differential equations may be used. Several criteria were proposed to define upper limit of "quasi-steady" relations of the metering orifice discharge.

The World Congress "Aviation in the X X I-st Century", 14-16 september [Текст] = Матеріали Всесвітнього конгресу "Авіація ХХІ століття" 14-16 вересня 2003 року / International Civil Aviation Organization; Ministry of Education and Science of Ukraine; National Academy of Sciences of Ukraine; National Aviation University. — Kyiv : NAU, 2003. — 438 p. : il.