Class 252 prototype HST at Weston-super-Mare in 1975 ※画像はWikipediaクリエイティブコモンズのパブリックドメイン画像を引用 Prototype
Main article: British Rail Class 252
See also: British Rail Class 41
Class 252 prototype HST at Weston-super-Mare in 1975
The prototype high-speed diesel train, which became the InterCity 125, was formed of a rake of passenger coaches between two power cars, one at each end. The decision to use two power cars was taken early in the project as design engineers calculated that the train would need 4,500 horsepower to sustain 125 miles per hour on the routes for which it was designed (the Great Western Main Line, Midland Main Line, and the Cross Country Route), and it was established that no "off-the-shelf" diesel engine was capable of producing such power. Another factor was that two locomotives operating in push–pull formation, would cause less wear on the rails than a single locomotive. The framework of the new locomotive, classified British Rail Class 41, was built at Crewe Works and transferred to Derby Litchurch Lane Works for completion. The design incorporated a driving desk around the driver, a sound-proofed door between the cab and the engine room, and, unusually, no side windows. The prototype was the first diesel locomotive in British railway history to use AC alternators in place of a DC generator, with the output converted to DC when used for traction.
The prototype train of seven coaches and two locomotives was completed in August 1972 and in the autumn was running trials on the main line. The following year, high-speed testing was undertaken on the "racing stretch" of the East Coast Main Line between York and Darlington. The set was reduced to two power cars and five trailers, and there was a concerted attempt to see how fast the train would go. On 6 June 1973, 131 mph was reached, which was bettered as the days passed. On 12 June a world diesel speed record of 143.2 mph (230.5 km/h) was achieved, and the drivers believed that 150 mph was possible, but the BRB issued instructions for the high speed tests to cease. It was believed at the time that this was because the BRB wanted to promote the APT as the future of high speed rail travel in the UK.
The fixed-formation concept was proven in trial running between 1973 and 1976, and British Rail went on to build 95 sets of production HSTs to transform InterCity services.
The cab fronts of three HST's at London King's Cross in 1981 ※画像はWikipediaクリエイティブコモンズのパブリックドメイン画像を引用
An InterCity 125 about to depart Manchester Piccadilly in 1986 ※画像はWikipediaクリエイティブコモンズのパブリックドメイン画像を引用
InterCity 125 at London Paddington in 1988. ※画像はWikipediaクリエイティブコモンズのパブリックドメイン画像を引用
First Great Western HST passing Old Oak Common Train Maintenance Depot ※画像はWikipediaクリエイティブコモンズのパブリックドメイン画像を引用
43002 has received vinyls of its original InterCity 125 livery to celebrate the 40th anniversary of the IC125 and named after the man that designed them, Sir Kenneth Grange. ※画像はWikipediaクリエイティブコモンズのパブリックドメイン画像を引用
Highland Chieftain InterCity 125 arriving at Haymarket ※画像はWikipediaクリエイティブコモンズのパブリックドメイン画像を引用
National Express liveried InterCity 125 in Central Scotland on the first day of National Express East Coast operations ※画像はWikipediaクリエイティブコモンズのパブリックドメイン画像を引用
Grand Central InterCity 125 set departing London King's Cross with a service to Sunderland in 2011. All Grand Central Class 43 power cars had exposed front buffers due to previous use as surrogate Driving Van Trailers (DVTs). ※画像はWikipediaクリエイティブコモンズのパブリックドメイン画像を引用
East Midlands Trains liveried HST at Leicester ※画像はWikipediaクリエイティブコモンズのパブリックドメイン画像を引用
East Midlands Trains InterCity 125 passing a Class 222 ※画像はWikipediaクリエイティブコモンズのパブリックドメイン画像を引用
HST power car in CrossCountry livery at Bristol Parkway. CrossCountry operates these trains on its northeast–southwest services. ※画像はWikipediaクリエイティブコモンズのパブリックドメイン画像を引用
The New Measurement Train speeds past the site of Clay Cross railway station in Derbyshire ※画像はWikipediaクリエイティブコモンズのパブリックドメイン画像を引用
1970年代のイギリス国鉄としては『ナウい！(笑)』ディーゼル高速列車、『インターシティー125(InterCity 125)』 
2月22日でみんカラを始めて13年が経ちます！
