Ramped dovetail rails for rotor blade assembly

摘要

A fan blade (34) of a gas turbine engine (10) includes a pair of root rails (54) disposed on a bottom (56) of a dovetail root portion (44) thereof. The pair of root rails (54) has a wedge-shaped contour and is tapered in a decreasing cross-section from the leading edge (50) to the trailing edge (52). The root rails (54) provide a wide, stable base for the blade to minimize tangential motion during windmilling. A pair of slot rails (76) is provided on the base (70) of a dovetail-shaped slot (40) retaining the dovetail root portion (44) of the blade (34). The slot rails (76) of the dovetail slot (40) mate with the root rails (54) of the dovetail root portion (44).