Delhi Metro will start inducting eight coach trains on its network by this December to tackle the ever-increasing rush and has begun conducting mandatory tests on a train that has been assembled.

The eight coach trains will be pressed into services on the busy Noida and Gurgaon corridors that record a combined daily footfall of over 13 lakh commuters.

Delhi Metro has already placed orders for procurement of 212 new coaches for conversion of six coach and four coach trains into eight coach trains.

By the year 2015, all the trains operational on Lines 2 (Jahangirpuri–HUDA City Centre) and 3/4 (Dwarka–NOIDA City Centre/Vaishali) will be either six coach or eight coach trains.

These additional coaches are scheduled to start arriving from September onwards and the first eight coach train is expected to be operational by the end of this year.

As part of the process, an eight coach train has been assembled at the Khyberpass Metro depot, on which various tests and examinations are currently being done.

"During the non-revenue hours in the night time, this train is also running from the Khyberpass to the Najafgarh Metro depot and vice-versa," Delhi Metro spokesman Anuj Dayal said.

Stringent 'Type Tests' are being done on this eight coach train, as part of which various aspects of Metro operations such as signaling, safety, speed pick up, jerking, breaking etc are being checked and observed.

These tests are expected to continue for another 15 to 20 days.

Dayal said the process of changing the number of coaches of a train involves lot of technical expertise for carrying out the necessary integration and commissioning activities.

A team of seven-eight dedicated DMRC engineers and contractors' engineers carry out several rounds of testing to make it ready for passenger service, he said.