At an old job I was qualified on the 727 for two engine ferries and did 4 or 5. Performance manual had a separate section of charts, MTOW was reduced from the normal 175,000 pound range to about 130,000. In recurrent training all Captains did a single engine landing because the FAA requires a landing with half the engines inoperative and there’s no provision for half an engine on planes with three engines. But at the end of the normal training and checking the instructor would reduce the weight of the plane and I'd do a two engine takeoff. Can’t remember if the instructor would fail an engine again to get down to one engine since the normal training included a takeoff with an engine failure and coming back again to shoot an approach and miss and have a second engine fail during the miss and then magically the weather got better for a single engine landing.