The first new commuter trains for the Greater Anglia fleet are expected to start testing in the region by the end of the year.

East Anglian Daily Times: One of Greater Anglia's Bombardier Aventra trains nearing completion at Derby Picture: GREATER ANGLIAOne of Greater Anglia's Bombardier Aventra trains nearing completion at Derby Picture: GREATER ANGLIA (Image: Archant)

But it will not be until well into 2020 that the British-built Bombardier Aventra trains enter service on trains from London to Essex, Ipswich, and Cambridge.

And Greater Anglia is facing a race against time to get all 111 electric trains into service on time by the end of next year.

The new commuter trains are the largest part of the company's £1.4bn investment to introduce a totally new train fleet across the region.

Swiss-built Stadler Flirt diesel/electric "bimode" trains have started entering service on rural and cross-country services out of Norwich are due to start operating on services from Ipswich to Lowestoft, Cambridge, and Peterborough over the next few months.

And the first new Stadler Intercity trains are due to enter service on the main line to London very soon.

But the commuter trains have taken longer than expected to arrive in the region - the first carriages were built at Bombardier's Derby factory last year but delays with completing similar trains for London Overground has delayed the Greater Anglia order.

However the first 100 carriages of the 655 destined for Greater Anglia have now been completed - the Aventras will be formed into five or ten carriage trains.

The first trains are now being run on the industry's test track at Old Dalby in Leicestershire before being sent to East Anglia to be tested on local lines.

However it will be a real challenge to get another 555 carriages built, fully tested and put into passenger service by the end of 2020 - officials from Greater Anglia are keeping the situation under constant review and there is mounting speculation that some existing electric suburban trains will still be in service in the region after the start of 2021.

Each train needs to clock up between 600 and 5,000 miles of fault-free running before Greater Anglia can put it into passenger service.

All of the new trains will be longer, with more seats, plug and USB sockets, free fast wifi, air conditioning, under-floor heating and better passenger information screens.

Ian McConnell, Greater Anglia franchise and programmes director, said: "We're looking forward to getting the first Bombardier train on our network.

"We've started replacing our diesel trains in the north of our network with new trains - and we know customers on the rest of the network are keen to see new trains on their routes too."

Alan Fravolini from Bombardier added: "We're really cracking on with these great new trains for Greater Anglia. Production is accelerating with a strengthened team and we are all focused on passenger service as soon as possible."