Known as AM9 units these were the first 'express' EMU built for overhead systems. The design was intended to become a standard for the main lines throughout the country but without ECML electrification and the WCML remaining with conventional locomotives and hauled stock just 76 vehicles forming 23 units were built in 1962 for the London to Clacton / Walton services on the GE main line. With a design speed of 100mph they were the fastest multiple unit until equalled in 1981.
The 2 car sets 601-608 were used for strengthening peak services while 4 car units 611-618 had the famous griddle car and 621-627 were the normal 4 car set. While the 4 car sets had a non-driving vehicle for the motor coach the 2 car sets could not, these being unique in having a leading motor coach with pantograph. The two variants are shown here.
The two car sets were made up to 4 cars by converting standard Mk1 hauled coaches between 1977 and 1980. The griddle cars ceased to be used in 1980 and were removed from the formations reducing 611 - 618 to 3 cars. As the units were refurbished [photo] between 1985 and 1987 further coaches were converted and all the units became 4 car.
For almost all of their working lives the class were confined to the London - Colchester main line and the branches to Clacton and Walton-on-Naze. The basic off peak hourly service was formed of a griddle and a standard 4 car set and split at Thorpe-le-Soken with one unit proceeding to Walton. From 1982 the Walton portion working ceased and most trains ran to Clacton. One through Walton service remained for commuters on Monday to Friday right through to 1994.
With the spread of electrification in the 1980's the class reached further into East Anglia, first on Harwich boat trains even before the wires had reached Harwich being dragged from Colchester. This also gave the class a named train, the 'Essex Continental' which was shown in some european timetables as through train D344 from Berlin/Kobenhavn/Bad Harzburg.
In 1987 and 1988 with power extended to Norwich they worked a number of Saturday services into Norfolk [photo] as well as commuter trains from Stowmarket
Portion working returned in May 1990 when Clacton and Harwich were served by a common train to & from London. From May 1991 Ipswich was served instead of Harwich. From May 1993 the class became confined to peak hour workings until the GE era came to an end 31 years and 14 days after it started on the 22nd January 1994.[photos] That day a 12 car ensemble of 616, 613 and 626 worked a diagram of 0800 CC-LV, 1000 LV-CC, 1200 CC-LV, 1400 LV-CC, 1600 CC-LV and finally the 1800 LV-CC.
A small scale return to service came with Northwest regional railways, later Northwest trains, using them on some Manchester commuter services. Plans to use them for regular Manchester - Birmingham services and also a Manchester - Crewe - Carlisle came to nothing. They did see some use outside the normal turns appearing on Manchester - London NWT services and also to cater for diverted aircraft passengers on Manchester Airport - London specials. They also worked on the Preston - Carlisle line during engineering diversions providing the Preston - Penrith rail service while through trains ran via Settle.
Final withdrawl of the surviving 6 units was on 27 May 2000, moving to storage at Shoeburyness with a 7th already withdrawn.
While five were scrapped from Shoeburyness in 2004, two units were converted in 2001 to signalling test trains intended for the WCML cab signalling project which never came through. These were 309616 (became 960101) and 309624 (became 960102). These were again stored at Shoeburyness MOD until bought for preservation in 2009.
The AC electrification of the North London Line in 1988 opened up several routes which were used for 309 powered excursions. Previous to this one had run from London Euston to Manchester and Hadfield when that line was converted to 25kV system, and there were also test runs over the WCML from Wolveton works or for high speed pantograph testing.
List of tours:
Euston - Hadfield 'Network Exile' 611/615 15 November 1986
St Pancras - Bedford (Station open day) 618 28 May 1988
Ipswich - Witton (Norwich - Everton cup semi footex) 606/615 15 April 1989
Colchester - York 601/611/621 23 June 1990
Colchester - Crewe HRT 'Cheshire Cheese I' for Crewe open day. 624/623/621 21 July 1990
Clacton - Liverpool St - Crewe HRT 'Cheshire Cheese II' for Crewe open day. 617/612/615 21 July 1990
Colchester - York 'Pudsey Express BBC Children in Need' 611/612 20 October 1990
Bishops Stortford - Clacton
Liverpool Street - Stansted - Ely - Hitchin - Southend - Norwich - Liverpool Street with legs to and from Clacton 626/624/602 15 January 1994
Manchester - Clacton via Liverpool Street 616/617/623 13 May 2000
The Crewe trips were unfortunately hampered by a 75mph limit on the units and the route via Northampton and Bescot. When routed over the ECML it was however a different proposition and performance was spectacular with significantly early arrivals as the units could keep up with stopping HST / class 91 schedules. Allowing for the vagaries of speedometers the highest speed that I can say I can believe is 108 at or near Hitchin.