the case of a single, relatively large prime-mover), breaking the locomotive up into long hood and short hood sections. It is generally preferred to run a hood unit short hood forward so that the cab is closer to the front, but there is enough visibility in the other direction that they can run long hood forward at regular speeds. Some railroad companies (notably, the Norfolk & Western and the Southern) ordered locomotives with cabs facing long hood forward so that the short hood is actually the rear of the locomotives, but that practice has become increasingly rare. This was usually done to offer greater protection to the crew in the event of a collision. Other locomotives were set up with dual control stands so that they could operate in both directions, making it unnecessary to turn the locomotive around at the end of a run. Some cabless hood units were also built. The long hood ran the whole length of those locomotives. In North America, all locomotives are required to have the letter F printed on the side sill at the end which is normally operated as its front. Freight-oriented hood units EMD GP7 EMD GP9 EMD GP20 EMD GP28 EMD GP30 EMD GP35 EMD GP38-2 EMD GP40-2 EMD GP50 EMD GP60 EMD SD7 EMD SD9 EMD SD24 EMD SD38-2 EMD SD39 EMD SD39-2 EMD SD40 EMD SD40-2 EMD SD45 EMD SD45-2 EMD SD50 EMD SD60 EMD SD70 series EMD SD75I EMD SD75M EMD SD80MAC EMD SD90MAC EMD DD35 EMD DD35A EMD DDA40X GE U23B GE U23C GE U25B GE U25C GE U28C GE U30B GE U30C GE U33B GE U33C GE U36B GE U36C GE U50 GE U50C GE Dash 7 Series GE Dash 8 Series GE Dash 9 Series GE AC4400CW GE AC6000CW GE Evolution Series Passenger-oriented hood units Brookville BL20GH GP40TC EMD GP40P EMD GP40P-2 EMD GP40PH-2 EMD GP39H-2 EMD GP40WH-2 EMD GP40-3H EMD GP40MC EMD SDP35 EMD SDP40 EMD SDP45 EMD SD70MACH GE U28CG GE U34CH GE Dash 8-32BWH MPI MP32PH-Q United Kingdom The term "hood unit" is not used in the UK but a few locomotives of the hood unit type are in service. Some of these locomotives may also be classified as cab forwards when running in reverse. British Rail Class 70 (introduced 2009) British Rail Class 08 (introduced 1952) British Rail Class 09 (introduced 1959) British Rail Class 20 (introduced 1957) Withdrawn hood