After trial runs and crew training British Railways first diesel multiple unit went into service at the start of the 1954 summer timetable on the 14th June, between Bradford (Exchange), Leeds (Central) and Harrogate. Two car sets operated on an entirely revised timetable, introducing an interval based service. They left from Leeds Central half-hourly from 8.06am to 11.06pm, and from Bradford Exchange half-hourly from 5.35am to 10.35pm. Some trains ran via Pudsey, but most via Stanningley, and a considerable number of runs were made non-stop. On Sundays one train each hour was a through train to Harrogate and Knaresborough and on the 20th June these had to run in duplicate.
On the first day, schedules appeared to be well maintained, although a few departures from Leeds were a minute or two late, apparently due to the drivers lack of familiarity with the controls. The evening trains were well filled, although the midday services were less well patronised.
At first, as only the first five 2-car sets had been delivered, three push-pull steam units with N7 Class 0-6-2Ts from the London Alexandra services were also in use. 79006/79506 were on trial on the 18th June 1954.
The sets captured the fancy of the general public: small groups of people gathered to watch them pass, many more travelled on them and the crews started getting outstanding performances from the sets. It was noted in the enthusiast press that the majority of the period's railway enthusiasts ignored them, preferring to continue the steam locomotive. They suggested though that in the future when these cars started to go there would be a lot of interest in them!
Before the sets were introduced, the fastest trains between Leeds and Harrogate took 30mins non-stop on the severely graded line which abounded in speed restrictions. The DMU timings were 27 mins down and 25 mins up, and timings gave the sets no difficulty. On a run between Harrogate and Leeds that was timed on the first few weeks, 19min 6 secs was recorded for the 15.1 miles from Harrogate to Headingley; from Headingley to Leeds the train the train was eased, but even so a time of 24 mins 41 secs for the 18.2 miles was achieved. This run included a slack of 19mph at Crimple Jct and 36mph at Arthington. A maximum speed of 60mph was recorded at Weeton.
Another timed run from the same period from Bradford to Knaresborough did the 9.3 miles from Exchange to a dead stand at Holbeck box in 13 mins 14 secs. The early running saw signal checks into Leeds Central, arriving at 17 mins 32 secs, or 17 mins 16 secs net. A late departure of 3 mins was soon made up. The 9.2 miles to Arthington South Jct in 11mins 55 secs with speeds of 53 at Headingley, 45 at Hursford and 55 at Bramhope Tunnel South. The remaining 9.0 miles to Harrogate took 11 mins 44 secs; this gave a net time of 23 mins 38 secs for an 18.2 mile non-stop run. The maximum speed (at Weeton) was 62mph. The timings were not unusual, and sustained 60 mph up a 1 in 100 and a maximum speed of 65mph were also noted.
Some difficulties were experienced with the air control connections, all the sets had to undergo modifications.
British Pathe produced a newsreel in 1954 - viewable on YouTube or their website featuring the new trains in action.
The sets proved very popular as anticipated, for example on Sunday 11th July over 1,000 passengers alighted at Knaresborough alone from the early trains, and the service from Bradford required duplicating. The entire service, including the extra trains was worked by four sets.
On the 18th June the seventh set, E79006/79506 was noted running trials.
In service on the 26th June were 79002/79502, 79003/79503, 79004/79504 and 79005/79505, as well as the push pull steam train - they were still in original formation at this time.
It did not take long for the West Riding sets to be mixed up. By August 79002 was running with 79506, and 79006 with 79502. The last set 79007/79507 had entered service before 23rd September 1954.
On Tue 19/10/54 West Riding set 79007/79507 headed north, carrying reporting no.92, arriving at Gosforth Car Sheds in the afternoon. The next day it made a trial run departing Newcastle at 09:35 for Middlesborough, calling at Sunderland and West Hartlepool. It returned from Middlesborough at around 11:40, and another round trip was made the following day. These were in preparation for future sets to be delivered.
Net receipts for the period from 14th June to 30th November 1954 saw a total rise in passengers of 203,643 and receipts grow by £14,773. The services were well used by shoppers that Christmas travelling to Leeds and Bradford.
In December 1954 the North Eastern Region was happy to announce that the first three and a half months of the more frequent services on the faster trains had led to net receipts increasing by £10,500 and passengers by over 125,000. An additional 80,000 passengers carried between Leeds and Bradford, with an increase in receipts of £4,558. Between Leeds and Harrogate there were increases of over 28,000 passengers and £3,474 in revenue. There was an increase of 14,723 passengers and £2,506 in takings on through traffic between Bradford, Harrogate and Knaresborough. This was despite the poor weather in the summer of 1954 which they thought would have reduced the number of pleasure trips. They also stated that the full scheme was not yet in operation and that further improvements to the service would be gained by adjustments to the services in 1955.
In Feb 1955, they announced that in the first five and a half months there had been an additional 147,329 passengers and receipts of £7,366 between Leeds and Bradford. Between Leeds and Harrogate there was an increase of 40,975 passengers and £4,665 in receipts. Through traffic between Bradford, Harrogate and Knaresborough had increased by 18,805 passengers and £3,108 in receipts.
Within five years income had grown to five times that of steam days. The annual operating savings from these sets was £183,675.