The blades of the GE36 UDF and the 578-DX have a maximum tip speed in rotation of about 750–800 ft/s (230–240 m/s; 510–550 mph; 820–880 km/h),[76] or about half the maximum tip speed for the propeller blades of a conventional turbofan.[77] That maximum blade tip speed would be kept constant despite wider or narrower propeller diameter (resulting in an RPM reduction or increase, respectively).[3]