Abstract: In a turbine or compressor blade and supporting disk assembly in which the assembly is by tangential positioning of the blades, the cooperating blade root and groove in the disk have base surfaces that are held in spaced relation to each other by a rib on the blade root extending toward the base surface of the groove and into contact with it.

Abstract: This invention relates to an improvement on material of a shroud for gas turbines. The material comprises 0.25-0.7 wt % C, 20-35 wt % Cr, 20-40 wt % Ni and balance Fe, and has an austenitic structure. The amount of the .sigma.-phase in this invention is less than 5% and Nv value (Electron Vacancy Number) is less than 2.8.

Abstract: A fan having reversible blades supported on a ring. The blades have means for holding the blades against rotation around thin central axis so that they can be selectively set to either blow cooling air forward away from the driver or rearward to add to the comfort of the driver. The resilient means urging the blades outward is made up of rubber cylinders that receive the hubs of the blades. One end of the cylinder rests on the fan while the thick end of the cylinder rests on the fan blades. The cylinder has a barrel shaped inside surface which it in giving the sleeved a generally uniform spring rate throughout its entire excursion.