The Wi-Fi hot spot service is being rolled out by Nomad Digital, which installed similar connectivity on Southern Trains' Brighton Express route and recently emerged as the preferred bidder to do the same for Virgin's West Coast line.

Although T-Mobile will be the operator for the service on the trains and at the stations, backhaul — the connection that will feed the Wi-Fi hot spots — will come via fixed WiMax, as is the case on Nomad's other projects.

As of early 2007, users will be able to buy access passes on board the train and continue to use them at T-Mobile's hot spots at Heathrow or in London. Similarly, holders of T-Mobile's access passes bought elsewhere will be able to use them on the Heathrow Express.