Prepared on Notepad by Ian Smith, best on Netscape 800*600

This page created 15th August 2001.

DMS 1

Construction: the first and second batches, DMS1-117

The original batch were fitted with the well-respected transversely-mounted Gardner 6LXB engine. The Park Royal bodies had a split entrance doorway, with the left half giving onto the driver for change-requiring transactions, while the right half admitted patrons to the miraculous automatic fare collection machinery (afc). Too bad if you had a wheelchair or pram. The centre exit doors had a no-entry light positioned beside them, and the driver could speak to people outside the bus through loudspeakers mounted in the window corners next to both doors. They seated 44 upstairs, 24 downstairs, with room for 21 friendly standing passengers. The staircase was located in the offside centre of the bus, with its foot opposite the exit doors and curling up forwards. All this within a shell 30' 10" long, 8' 2½" wide and 14' 6" high.
Drawing of original batch DMS.
Livery was unrelieved red, in order to allow maximum advertising space. The fleetname was in the form of an open bullseye, with LONDON TRANSPORT in white across the centre bar.
The front sported a three-panel display, with the route number display back on the nearside (unlike the Routemaster and the XFs). The nearside and rear had number displays only.

DMS 1 and DMS2 appeared at the Commercial Motor Show at Earl's Court in September 1970, appearing for Park Royal and Daimler respectively (both sporting British Leyland badges for the occasion).
London Transport received DMS 1 immediately after the show, followed by DMS2-11, 16-25 in October, and DMS 26-50 in November, and the missing numbers (except for DMS14) plus DMS 51-72 and 74 in December. They went variously into store or into intensive training as mechanical trainers, driver trainers, route surveyors and decimal currency trainers.

Their service debut was in January 1971.

Details of their service introduction.

1971-2: the third batch: DMS118-367

2/1DM1/2 DMS132 at Cobham April 99
Above:Drawing of 3rd batch DMS.
Right:White-banded DMS132 at Cobham Open Day in April 1999 still has the original headlight style, but white-band livery (Photo by Ian Smith)
The most noticeable change with the third batch was cosmetic: a broad white band on each side that greatly relieved the tedium of the red slabs of the first batch. Next, and more permanent, from DMS168 onwards the headlights were further apart, on the wing panels rather than the centre panel. The sidelights moved up to accommodate them. Less obvious, because they had not been much used, was the loss of the exterior public address speakers and the no entry lamp beside the exit doors. Inside, a heater cover was redesigned and the front grab-rail remodelled. From DMS168 onwards this all occasioned a new body code: DM1/2.

The batch of 250 buses was delivered between June 1971 and March 1972.

Details of their service introduction.

1972: Enter MCW.

By now the Fleetline ball was really rolling. Another 1600 buses had been ordered for delivery over the next three years, with the order split several ways. Park Royal Vehicles and Metro-Cammell-Weymann shared the body orders, with the numbering scheme divided beteen them: Park Royal would eventually do DMS368 to DM1217, while MCW would do DMS1248 to DMS1967 building concurrently, with MCW taking over DM1218-1247 from PRV. Each manufacturer would do batches of DM buses (DM918-1217 for PRV, DM1703-1832 and DM1218-1247 for MCW). There were also batches with Leyland O.680 engines in place of the Gardner 6LXB, plus a few with Rolls Royce Eagle engines.

The new buses: DMS368 - 585 (PRV); DMS1248 - DMS1415 (MCW), (approx)

MCW DM4 The new Park Royal buses, classified DM3, looked just like the third batch, except that livery had returned to dull overall red. The MCW bodies, classified DM4, looked very similar at first glance. It was only when you became familiar with them that the differences became obvious. (Paul Watson pointed out quite a few to me when I started doing the drawings for him). Most apparent were the bodywork beadings, especially around the edge of the roof: MCWs had a prominent moulding, Park Royals didn't. On the offside the emergency doors were differently shaped, MCW's being taller with a rounded top, while PRV's effort was square topped under a little gutter. Even the drain-holes for washing out the upper deck were different shapes: MCW's were round, PRV's rectangular. Bus nuts notice these things! Less obviously, MCW's window pans abutted, with just a beading to cover the join, while Park Royal's needed a narrow panel between windows. ( I didn't know: Paul Watson told me). Inside, laminates replaced rexine on walls and seat backs.
Drawing of early MCW DMS.
It had been intended to keep the MCW and Park Royal batches at separate garages, to minimise spares-holdings, but that idea did not last even as long as the first MCW allocation to Bromley, although there were attempts with other allocations to keep it that way. Keeping the number sequences separate helped enormously.

Details of their service introduction.

The "1973" buses: DMS586- (PRV); DMS1416- (MCW)

PRV DM3, yellow doors By the end of March the 1973 batches of buses were coming on stream from Park Royal and MCW, incorporating new features and a new livery: Details of their service introduction.

The 1974 afc campaign

PRV, red/yellow doors London Transport was understandably concerned at the long stop-times on omo buses. Part of the problem was the customers' reluctance to use the afc machines. So from May 1974 LT ran a three-month trial campaign to encourage afc use, with DMSs on route 10 and SMSs on the 227. Buses were painted with a red entry door leading to the driver, and a yellow door for the afc machines. Large posters pointed to the yellow door, and colour coding was introduced for the four fare values available. The effect of the campaign was marginal, and attributable to the large number of inspectors employed to assist with the machinery. The campaign ended after three months without being spread further, although some buses retained their odd doors for some time.

The Eagle has landed: DMS864, and other bus developments


1974: Crewed DM Fleetlines, and the flat-fare DMS.

DM1117 The 1973 decision to restrict the changeover to one person operation, and hence to keep the RMs and dispose of the Merlins impacted on the DMS programme. More Fleetlines would be needed as DM crewed buses. A substantial number of DMS buses were placed onto crew-operated routes in late 1973, the 16 (Cricklewood), the 135 (Potters Bar and Wood Green), and the 149 (Stamford Hill and Edmonton). This was a temporary measure. By September 1974 the purpose-built crew Fleetlines began to arrive, and started to displace the crew-operated DMSs. These returned to Aldenham for the fitting of fare-collection equipment and appropriate notices. Then most of the ex-Cricklewood buses went to Wood Green to replace the flat-fare Merlin MBSs, and were fitted in consequence with the machines off the Merlins as they came off duty.
DM1117. Photo (used with permision) by Paul Watson

PRV DM3, yellow doors The DM buses were not much different from the DMSs. They even had yellow doors! (So much for the yellow doors for auto-fare idea!) Inside there were no afc cabinets. A glass partition stood behind the doorway where the cabinet front had been, with a bench seat for three. Standing was limited to five. The transfers applied to the front invited passengers to pay the conductor. An external visual identifier was the raised number plate (although this was on later DMSs too). It was now mounted above the detachable plate over the towing point. These were used so often that there was a real risk of plates ending up on the wrong buses!

1974-75: more DMs and DMSs

1974 and 1975 continued with DMs and DMSs continuing to replace RTs and MBSs. But London Transport was less than enamoured with its performance, especially the running costs and lack of reliability. The former, where LT had hoped to make substantial savings by converting to opo, had risen substantially through the need for extra buses to maintain route capacity because the buses were so much slower, and because of increased maintenance costs and down-time, related to problems with the gearbox brake-bands and to enmormously increased brake wear. The depths were plumbed with the Februaery 1975 delivery to Wandsworth of 27 new buses from Leyland's Farington plant. Without consulting LT the design of the gearbox brake-bands had been altered, leading to failure of half of Wandsworth's allocation within three months!
LT began to look for alternatives, leading to the Metro-Scania MD and the Leyland Titan.

Another problem was late deliveries. In an effort to speed things up London Transport shifted thirty buses (DMS1188-1217) from Park Royal's order-book to MCW's, giving a hiccup in the number blocks, with these latest MCWs taking numbers below the original MCW block.

1976:"White-tops": DMS1968-2057, 2167-2246 (MCW), DMS2058-2166 (PRV)

MCW DM7, white-top In March 1976 the updated design entered service: the DM7. These had two-piece glider doors, in place of the four-piece folding doors, pantograph windscreen wipers on the nearside windscreen, fitted internal fire extinguishers, fluorescent tubes in the blind boxes and a cover over the rear-blind handle. They were also now officially Leyland Fleetlines, rather than Daimler Fleetlines, with emblems to match. They were easy to recognise, as they wore the livery that had been experimentally tried on DMS 46 in 1974: a white surround to the upper-deck windows. This livery became a standard for modern LT double deckers (DMS, MD, M and T) for a while, until the dead hand of accountancy was re-applied.
Three (DMS1968, DMS 2059 and DMS2120) joined DM1199 as recipients of Rolls Royce Eagle engines.

Delivery of this batch lasted into 1978, the last being delivered alomgside the B20s.

The quiet B20s

B20, white-top London Transport was ahead of noise-limitation legislation with the B20. One of the public criticisms of the DMS had been the noise inside, whether they were powered by Leyland O.680 or Gardner engines. The B20 was fitted with a quietening kit, with a turbocharged engine fed with air through a cowl drawn through a cowl where the offside cosmetic hood had been. Air from the cooler group exited by a cowl on the nearside. The asymmetric cowls increased the bus length by 6cm, and reduced the width of the rear saloon window. This in turn was fitted with a magnifier to widen the angle of view.

They went into service at Bexleyheath in March 1978, with great expectations. But they were short-lived. It seemed that the B20 was no more reliable than the earlier "Standards". One additional problem was created by the filler for the power steering, which was high inside the cowl above the engine. The sight-glass was difficult to see, and the inevitable overfilling was dealt with by a drip tray. But when that overflowed oil dripped onto a hot engine. Bad news!

Next: Part 3: Service Introduction - the details.

Bus Stop Part 1. Part 2. Part 3: Into service. bus histories. photo refs.