Chassis

The Trident 3 chassis was developed from Dennis Lance/Arrow. It had a longitudinally-mounted rear engine, with a radiator mounted on the right hand side of the engine. An auxiliary axle was mounted behind the second axle to cope with the weight at the rear and reduce the rear overhang.

Trident 3 was available in 4 different body lengths: 10.3m, 10.6m, 11.3m and 12m.

Engine

The engines used for these buses were all manufactured by Cummins. Earlier models use M11-305E, a 305-hp engine comply with Euro II standards, or ISM-330 330hp engine for the buses delivered to North America.

The M11-305E engine was replaced by Cummins ISMe Euro III-standard engine in 2001. A 330hp version (ISMe330) was used initially, but later models in Hong Kong adopted a 335hp (ISMe335) version.

Gearbox

Initially the options of gearbox included Voith DIWA863.3 and ZF 5HP590. Later Voith DIWA864.4 and DIWA864.3 gearbox were also chosen, but both were replaced by Voith DIWA864.3E gearbox.

For Euro III-engined Tridents, almost all of them were fitted with Voith DIWA864.3E gearbox, only 10 were fitted with ZF 5HP602 gearbox.

The prototypes

Six prototype Dennis Trident 3 chassis were built in 1996.

The first Trident 3 chassis was delivered to Alexander in late 1996 and received a body with the front resembled to R-type design. It was retained by Dennis as a development vehicle.

The other 5 were all delivered to Hong Kong, two went to Kowloon Motor Bus and three to Citybus.

Hong Kong

New World First Bus

It was rumoured that China Motor Bus (CMB) had thought about purchasing ten Tridents in late 1996, but due to unpredictable delivery time Condors were bought instead. When New World First Bus won China Motor Bus's franchise in early 1998, plan was put forward of buying Tridents. Tridents have now accounted for over 50% of buses in its fleet.

First batch (1998 - 1999)

Three batches of NWFB Tridents are 12 metre in length, including the first batch of 160 Alexander-bodied Tridents and 42 Duple Metsec bodied Tridents, both entering service starting from late 1998. NWFB assigned two different number schemes for these Tridents according to their bodywork (1001 onwards for Alexander bodied ones, and 3001 onwards for Duple bodied ones).

Second batch: Shorter variations (1999 - 2000)

NWFB's 10.3m Trident 3 (3309) with Duple Metsec bodywork.The second NWFB batch entered service throughout 1999 as well as early 2000. NWFB adopted a policy of purchasing shorter variations of Tridents in its second batch. 50 buses of this batch were still 12 metres in length (30 with Alexander ALX500 bodywork, and 20 with Duple Metsec bodies), but all others have a shorter length.

Thirty 11.3-metre Tridents entered service in 1999, along with sixty-two 10.6-metre ones. All these 92 buses were with Alexander ALX500 bodywork, and quickly replaced the old buses inherited from CMB.

A slightly later batch of 40 Tridents were fitted with specially-designed Duple Metsec bodywork. They were 10.3m (34ft) in length and 4.17m (13.7ft) in height, about a feet lower than standard models. These buses were designed for both height and length restrictive road conditions in the hills of Hong Kong Island, including the ones leading to The Peak. These buses' fleet numbers originally included an "L" at the end, but removed some years later.

Last batch (2000 - 2002)

NWFB's 12m Trident 3 (1220).A 10.6m Trident prototype was acquired by NWFB in 2000, but the next Trident batch came only two years later. 41 Tridents with Euro III standard engines entered NWFB in 2002. 21 of them were of Alexander-bodied 12m version, while the other 20 were 10.3m special editions. Essentially, the last special edition buses are also the last of Duple Metsec-bodied Tridents.

Redundancy

NWFB's expansion in its early years proved to be too fast, and redundancy grew up fairly quickly. Many of its buses were sold elsewhere in order to archieve better utilisation. Nine 12-metre Tridents in the last batch (Fleet number 1201-1209) were transferred to Citybus in 2003, only one year after their entry of service.

53 Tridents were transferred to the bus division of KCRC starting in 2004. All of them were shorter Alexander-bodied versions, with forty-seven 10.6m ones and six 11.3m ones.

Further development

In 2002, the Trident 3 chassis was modified and then introduced as a complete bus, which was known as TransBus Enviro 500.

Dennis Trident 3. (2007, August 23). In Wikipedia, The Free Encyclopedia