Once when I was a teenager, out for a bike ride with my mates, I stopped to take a picture of the formerly triangular Ambergate Station, where the former Midland Railway main lines from Derby to Manchester and Sheffield bifurcated.

Decades later, I showed this image to an evening-class group in Matlock and, while the nice old ladies listened patiently, the rail enthusiasts in the audience began to make ecstatic noises.

It turned out that the locomotive in the picture was a considerable rarity.

Even I could see it was non-standard, painted in red ochre, with a centre cab and long bonnets concealing the engines.

This was an example of British Railways Class 17, known colloquially as “Claytons” after their manufacturer, one of a number of pilot designs commissioned after the decision was taken to replace steam traction with diesel under the 1955 Modernisation Plan.

The Claytons were a notorious result of indecisive and confused planning, undue haste to deliver untested innovatory designs, and the sheer stupidity of ordering off-plan without waiting for a prototype to be completed.

Built by Clayton Engineering Company and Beyer, Peacock & Company between 1962 and 1965, the design was an attempt to devise a single-cab locomotive with adequate visibility for the driver.  It failed.

Earlier prototypes had followed the pattern of the American “switcher” shunter, with a cab at one end behind a single large power unit.  Like the steam locomotives they replaced, which traditionally placed the cab behind the boiler and firebox, they gave the crew a limited view of the road ahead.

Providing adequate sight-lines from the Claytons’ single central cab necessitated twin power units, low enough for the driver to see past them, and these were inadequate and unreliable.  Indeed, the sightlines were still unsatisfactory because the length of the bonnets masked the track immediately ahead of the front buffers.

Some of the later deliveries of Class 17 were immediately withdrawn from the active list and stored.

After the last of 117 Class 17 locos had been delivered in 1965, the first withdrawals took place in 1968, and by 1971 they were all scrapped except one, D8568, which was sold for industrial use and is now based at the Chinnor & Princes Risborough Railway, Oxfordshire, where it operates from time to time.