Bombardier's Derby Site, commenced construction of the first new train for the London Underground's sub-surface lines on 3 July 2007.  The underframe is the first component of the carbody to be assembled.  Aluminium extrusions are fitted into the main welding fixture and production operatives control a robot welder to produce a strong and high quality join along the entire length of the underframe.

The first complete carbody will be fully assembled during August.  It will then undergo strain-gauge testing in Bombardier’s Engineering Development Laboratory to prove its structural integrity.  

Bombardier has the contract with Metronet Rail to supply a single fleet of trains to replace the 177 trains of different types which operate on the Metropolitan, District, Circle and Hammersmith & City lines.  Bombardier’s contracts also include the provision of an entirely new signalling system for the sub-surface lines as well as fleet maintenance for the rolling stock.