The BR Blue Class 121 Add-On Livery requires the Network SouthEast Class 121 DMU add-on to be installed, this is also available on Steam.
Arguably the most useful of first generation diesel multiple units (DMUs), the Class 121 ‘Bubble Car’ comes to Train Simulator in distinctive BR Blue livery.
The unusual single-car units were manufactured by Pressed Steel Company from 1960 onwards and introduced by British Rail for use mainly on the Western Region and around London on suburban and branch line duties. Their distinctive exhaust pipes designed to fit around a large four-digit headcode indicator box made these units fondly regarded by rail fans for their unpretentious appearance and old-fashioned interior and performance characteristics.
The ‘Bubble Cars’ became familiar for running Network SouthEast services and upon privatisation of British Rail, the fleet was operated by only one passenger company – Silverlink – with several more units in departmental duties with Railtrack. Today, two Class 121 models remain in revenue generating service with Chiltern Railways, representing the last chance to ride on 1960s slam-door stock on the main line in the UK and signifying a remarkably long life for these fans’ favourite. Five motor cars also remain in preservation across heritage railways in the UK.