U sets

U set
Preserved driving car CF 5003 at Junee Roundhouse Railway Museum
In service	1958 - 1996
Manufacturer	Commonwealth Engineering
Built at	Granville
Constructed	1957 - 1960
Entered service	September 1958 - March 1960
Number built	40 motor cars, 20 trailer cars 20 non-smoking trailer cars
Number in service	0
Number preserved	14 motor cars, 23 trailer cars
Formation	4 car sets
Fleet numbers	CF 5001-40 TF 6001-20 ETB 6021-40
Operator(s)	New South Wales Government Railways Public Transport Commission State Rail Authority CityRail
Depot(s)	Flemington Maintenance Depot
Line(s) served	Blue Mountains Newcastle Illawarra
Specifications
Car length	20.57 m (67 ft 6 in)
Width	2.95 m (9 ft 8 in)
Height	3.92 m (12 ft 10 in)
Maximum speed	70 mph (113 km/h)
Weight	49 long tons 8 cwt (110,700 lb or 50.2 t)
Traction system	4 Metropolitan-Vickers series-wound DC traction motors per motor coach, each rated at 180 hp, semi-automatic resistance control. The master controller handle allows for the manual selection of First Series (1), Full Series (2) and Parallel (3) connexions, two field weakening settings (4, 5) for high speed operation. There is also an 'emergency acceleration' button.
Transmission	traction motor geared to road wheels by pinion and crown wheel
Electric system(s)	1,500 V DC catenary
Current collection method	Single-pan diamond pantograph
Braking system(s)	Westinghouse Brake & Signal Co electro-pneumatic and automatic air brakes, brake blocks active on all wheels
Coupling system	automatic coupling
Multiple working	MU capable in various formations
Track gauge	1,435 mm (4 ft 8 1⁄2 in)

The U sets were a type of electric multiple unit operated by the New South Wales Government Railways and its successors between September 1958 and November 1996. They were nicknamed U-boats.

The New South Wales Government Railways began planning the electrification of the Main Western line over the Blue Mountains from 1949, and with that plan in full swing by the early 1950s, called tenders for 80 cars (40 motor, 20 trailer and 20 first with buffet trailer), with the contract was awarded to Commonwealth Engineering, Granville in 1954. Electric traction equipment was supplied by the Metropolitan-Vickers, Manchester. However, before construction began the order was amended with the 20 planned first with buffet cars built as full first class seating cars, after a review of the New South Wales Government Railways conducted by American firm Ebasco Services Incorporated in the mid-1950s recommended the change.

The U sets were a bit different compared to the that were delivered at the same time. They were the first EMUs in NSW to feature stainless-steel construction using technology from the Budd Company, improving train acceleration and giving the trains lower maintenance costs and a longer usable life.

The U Sets started to be delivered from June 1957, and the first sets made their first public appearances that same year. The first appearance took place on 22 June 1957 when they were hauled by electric locomotive 4612 as part of the first train to travel on the newly electrified Blue Mountains line. Normal services began on 15 September 1958, and all were in service by March 1960.

The cars were numbered as:

First class travel was abolished on 1 September 1974. This saw the removal of the word "Second" on all carriages and also allowed non-first class passengers to enjoy the benefits of non-smoking carriages for the first time.

The U sets initially entered service on the Main Western line to Bowenfels which was cut back to Lithgow in 1974. As the electrified network expanded they began to operate to Gosford (January 1960), Wyong (April 1982), Newcastle (June 1984), Port Kembla (February 1986) and Dapto (January 1993). The U sets were supplemented by V set double deck sets from 1970.