An aircraft engine system comprising: a turbofan engine; a lubricating oil system (14,16); a cooling circuit having a bleed air boosted engine oil cooler assembly and heat exchangers (24, 32) connected to provide oil cooling to supplement the bleed air boosted engine oil cooler assembly; an oil pump connected to pump oil from the lubricating oil system (14,16) through the cooling circuit to the turbofan engine, wherein the bleed air boosted engine oil cooler assembly comprises: a liquid/air heat exchanger, LAHEX, connected to an oil inlet conduit and receiving fan air from a high bypass fan of the turbofan engine as a cooling working fluid, said LAHEX connected to an oil exit conduit, and an ejector downstream of the LAHEX receiving bleed air from a compressor section of the turbofan engine, said ejector drawing the fan air through the LAHEX; and wherein the heat exchangers comprise a main fuel/oil liquid/liquid heat exchanger, LLHEX, connected to provide oil cooling employing fuel, pumped from aircraft fuel tanks through feed lines for use by engine combustors, as a liquid cooling working fluid through a first feed line receiving fuel from a fuel pump supplying the fuel to a combustor supply inlet, the main fuel/oil LLHEX connected to the oil exit conduit; and a servo fuel heater LLHEX connected to bypass fuel from a second stage fuel pump through a servo loop, said servo fuel heater LLHEX connected to the oil inlet conduit. a turbofan engine; a lubricating oil system (14,16); a cooling circuit having a bleed air boosted engine oil cooler assembly and heat exchangers (24, 32) connected to provide oil cooling to supplement the bleed air boosted engine oil cooler assembly; an oil pump connected to pump oil from the lubricating oil system (14,16) through the cooling circuit to the turbofan engine, wherein the bleed air boosted engine oil cooler assembly comprises: a liquid/air heat exchanger, LAHEX, connected to an oil inlet conduit and receiving fan air from a high bypass fan of the turbofan engine as a cooling working fluid, said LAHEX connected to an oil exit conduit, and an ejector downstream of the LAHEX receiving bleed air from a compressor section of the turbofan engine, said ejector drawing the fan air through the LAHEX; and a liquid/air heat exchanger, LAHEX, connected to an oil inlet conduit and receiving fan air from a high bypass fan of the turbofan engine as a cooling working fluid, said LAHEX connected to an oil exit conduit, and an ejector downstream of the LAHEX receiving bleed air from a compressor section of the turbofan engine, said ejector drawing the fan air through the LAHEX; and wherein the heat exchangers comprise a main fuel/oil liquid/liquid heat exchanger, LLHEX, connected to provide oil cooling employing fuel, pumped from aircraft fuel tanks through feed lines for use by engine combustors, as a liquid cooling working fluid through a first feed line receiving fuel from a fuel pump supplying the fuel to a combustor supply inlet, the main fuel/oil LLHEX connected to the oil exit conduit; and a servo fuel heater LLHEX connected to bypass fuel from a second stage fuel pump through a servo loop, said servo fuel heater LLHEX connected to the oil inlet conduit. a main fuel/oil liquid/liquid heat exchanger, LLHEX, connected to provide oil cooling employing fuel, pumped from aircraft fuel tanks through feed lines for use by engine combustors, as a liquid cooling working fluid through a first feed line receiving fuel from a fuel pump supplying the fuel to a combustor supply inlet, the main fuel/oil LLHEX connected to the oil exit conduit; and a servo fuel heater LLHEX connected to bypass fuel from a second stage fuel pump through a servo loop, said servo fuel heater LLHEX connected to the oil inlet conduit.