Known originally as the High Speed Train (HST), and still known by that name to railwaymen and railway enthusiasts, it was soon marketed to the public as the InterCity 125. This train gradually became a familiar sight on all of the principal routes across the country.
Its design was a huge advance on the previous trains. However, the features could better be described as evolutionary, rather than revolutionary.
The HST designers were goaded into creating it because the truly revolutionary Advanced Passenger Train (APT) was making such slow progress.
The APT was being designed by people from the automotive and aircraft industries. As a result perhaps, the design contained too many innovations. Eventually, the government withdrew its support for the APT.
The really clever bit, however, was the tilting mechanism, so that went to Fiat. Fiat then used it as the basis for the Pendolino, which was sold on to many railways, including Britain’s Virgin Trains.
The designers of the HST were British railwaymen. And they produced the new train by setting self-imposed targets in order to deliver improved performance.
Most trains of the time were 90mph designs so this one had to be able to run at 125mph. However, it also had to be able to stop in the same distance as a 90mph train.
To meet some of the design criteria, the train had two power cars, one at each end. This was instead of being hauled by a locomotive at the front. But it still had to be able to run at 90mph on just one of the power cars.
Instead of being built up on a chassis, the passenger coaches were steel tubes. They had holes cut in them for the doors and windows, which made them immensely strong.
In my opinion, the designers failed in two important features.
The young innovators wanted automatic doors. However, the older, established designers, who were in the positions of authority, were nervous that the technology might be too new. They were concerned that automatic doors could give rise to costly failures, so, they opted to have old-fashioned, slam doors instead.
Consequently, for more than 40 years the railway staff have had to run up and down shutting doors which passengers have left open. The doors have also been quite difficult to open from inside the train.
The other failure was to include toilets that emptied directly onto the railway tracks.
Both these failures are now having to be rectified at great expense by the current operators, such as Scotrail, which plans to keep the trains in service after 2020.
Although the design is more than 40 years old, the trains are still good to go. They have been re-engined more than once. Quieter engines have replaced the originals, which were sourced from the Royal Navy, having been used in motor torpedo boats. The interiors have also been refurbished many times.
The worst thing about the HSTs has been that their performance is so good that the powers-that-be have always seen little incentive to electrify the lines.
And passengers are still suffering from this today.
John Wylde is author of Integrated Transport – a Will-o’-the-wisp?, priced £14.95, post paid and signed by the author. Also Experiments in Public Transport Operation’, at £11.95. Order through www.john-wylde.co.uk or from Grieves on the corner of Church Street in Berwick.