an annular casing;

a disk disposed coaxially inside said casing and including a row of fan blades extending radially outwardly from a perimeter rim thereof;

each of said blades including an airfoil having circumferentially opposite pressure and suction sides extending radially in span from a root to a tip, and extending axially in chord between opposite leading and trailing edges, with said airfoils defining corresponding flow passages therebetween for pressurizing air;

each of said airfoils including stagger increasing between said root and said tip to position the leading edge of one airfoil circumferentially adjacent to the suction side of the next adjacent airfoil to define a mouth for said flow passage therebetween, with said flow passage converging to a throat aft from said mouth; and

said row including no more than twenty and no less than eighteen of said fan blades having a solidity defined by the ratio of said airfoil chord over the circumferential pitch and being low in magnitude at said tips and no greater than about 1.2 and greater than about 1.0 to position the leading edge of each tip circumferentially near the trailing edge of the next adjacent tip.