U Set

The U sets were a class of intercity electrical multiple unit (EMU) operated by the New South Wales Government Railways (NSWGR) and successor organisations between September 1958 and November 1996.

Development
NSWGR began planning the Blue Mountains electrification from 1949, and with that plan in full swing by the early 1950s, they called tenders for 80 cars (40 motor cars, 20 trailer cars and 20 planned first with buffet trailer cars), of which the contract was awarded to Commonwealth Engineering (Comeng) of Granville in 1954. However, the 20 planned first with buffet cars, which would have been coded RT 6601-20, were replaced by 20 full First-class seating cars just before construction began, after a 200-million pound review of the NSW Railways took place by American firm Ebasco Services Incorporated in the mid-50s recommended the replacement of these cars.

The U sets were slightly different compared to the suburban single-decked trains that were running at the time. They were the first EMUs in NSW to feature the stainless-steel construction (earlier NSWGR EMUs featured painted mild steel or were of wood construction, of which was found on the "Bradfield" EMUs, also the oldest and first electric multiple units in NSWGR service at the time), improving train acceleration and giving the trains lower maintenance costs and a longer usable life.

They were not fitted with air-conditioning, instead having opening windows.

They are one of the few trains that are approved to run on tracks with the narrow track width classification, being 2946mm wide.

Delivery
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 the 22nd June 1957 when they were hauled by electric locomotive 4612 as part of the first train to travel on the newly-electrified Blue Mountains network. Normal services began on the 15th September 1958, and all of the members of the type were delivered by March 1960.

The cars were numbered as:
 * Second-class Motor Cars-CF 5001-40
 * Second-class Trailer Cars-TF 6001-20
 * First-class (non-smoking) Trailer Cars-ETB 6021-40

First class travel was abolished on 1 September 1974, so therefore all cars were changed to one-class after 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).

In service
The cars were used on interurban services from Sydney to Newcastle, Port Kembla and Lithgow. These trains were supplemented by the double-decked V sets from 1970 until their final withdrawal in November 1996.

The trains could be found mostly on the Lithgow-Sydney services, especially after the V sets started running more services during the 1980s. Like their normal suburban single-deck cousins, halfway through their service lives most got their original lift-up windows replaced by Beclawat sliding windows.

Withdrawal and Preservation
The U Sets (and their older suburban single-deck brethren) were withdrawn from 1988 onwards when the Tangaras started entering service across the CityRail network. The suburban single-deck stock were all withdrawn by 1993 and the U Sets by 1996.

Most of the U Set stock are preserved and some are operational. Out of the 40 motor cars, 20 trailer cars and 20 non-smoking trailer cars built, only 14 motor cars and 23 trailer cars have been preserved:
 * The Sydney Electric Train Society (SETS) owns 10 examples - non smoking cars ETB 6037 and ETB 6038, trailer cars TF 6006 and TF 6010, and motor cars CF 5003, CF 5006, CF 5010, CF 5021 and CF 5022.
 * Only 5003/5006 are approved by TfNSW to run on Sydney Trains lines and are only approved to run with motors and toilets disabled
 * A few are owned by Transport Heritage NSW for preservation
 * The Glenreagh Mountain Railway and Richmond Vale Railway also own trailer cars.