The States of Guernsey has ordered 22 additional Euro 6 Wrightbus StreetVibe buses, equipped with Cummins ISB4.5 engines mated with allison T 2100 automatic gearboxes for increased performance, faster acceleration and greater operational flexibility.
It follows an initial order of 12 buses delivered in 2017.
The States of Guernsey owns the island’s fleet of 42 buses, operated by HCT Group subsidiary CT Plus Guernsey under contract.
When replacement of the predominantly Euro 3 Dennis Dart bus fleet began in 2017, the 9.04m, 2.28m wide Wrightbus StreetVibe was selected as the narrowest bus in its class, with a seating capacity of 31 plus 11 standing.
To be compliant with the island’s 25mph speed limit for vehicles over two tons, the buses are fitted with a limiter.
Yet the hilly roads demand pulling power – but not at the expense of fuel economy. As a result, says the operator, it found Allison’s T 2100 automatic adaptable to challenging terrain.
The fully-automatic transmission increases power while a manual- or automated manual transmission (AMT) loses power with every shift. Allison’s patented Continuous Power Technology delivers smoother, seamless, full-power shifts and superior acceleration and startability, it says.
“The roads on Guernsey are narrow and winding with a terrain that varies wildly,” said Karl Guille, Director of Traffic and Highway Services for the States of Guernsey.
“You can be in typical rush hour town traffic, with stop-start driving one minute, and need to accelerate smoothly up a steep hill the next.”
“We also needed as narrow and short a vehicle as possible, but with a minimum capacity of 40 passengers and superior manoeuvrability,” says Mr Guille.
“The Euro 6 StreetVibe Ultra Low Emission Bus (ULEB) from Wrightbus has met our needs with a solution that has significantly reduced particulate matter and nitrogen oxide emissions, is much quieter and has improved fuel economy by up to 20%.”
HCT Group Operations Manager Lee Murphy says: “Allison Transmission has been an excellent partner in getting the bus package right for us, which has made the decision to reorder the same vehicle specification an easy one.”
Because of the favourable torque characteristics of the Allison transmissions, “maintenance costs have been reduced too,” he adds.
