May 2017 and the Bubble Cars bow out

Shortly before 21.00 hrs. on Friday, 19 May 2017, a piece of railway history was made when the two 1960-vintage Class 121 “Bubble Cars” that had been in service with Chiltern Railways completed their last ever run from Princes Risborough to Aylesbury.

Paying my respects to the 57 year-old machines on Thursday, 11 May 2017, just eight days before the end, there were already a good number of enthusiast passengers travelling the 7½-mile branch line, on a day when services were in the hands of BR green-liveried W55034 (121034), seen above awaiting departure from Aylesbury.

Chiltern Railways had originally acquired W55020 (121020) 14 years earlier, in April 2003, in order to free up one of its two-car Class 165 units for peak-time use elsewhere and, after extensive overhaul, it was painted in the company’s attractive blue livery.

The second Bubble Car (W55034) had only been acquired in May 2011, but was covering services on 11 May while W55020 remained at Aylesbury depot (pictured above with W55034 as GBRf 66720 passes on a spoil train for Calvert) with engine problems that had kept it out of service for several months.

The Aylesbury-Princes Risborough branch is a pleasantly rural line, with two little-used intermediate stations at Little Kimble (above) and Monks Risborough (below) and a modest level of passenger traffic that could easily be handled by the 65-seat Class 121s.

A total of 16 were built for the Western Region of British Rail (W55020–W55035), and saw service on a wide variety of routes, including Cornish branch lines, the Bridport branch,  the former routes of the Southern Railway’s “withered arm” to Bude and Padstow, as well as Bristol Temple Meads-Severn Beach and Greenford-West Ealing.

W55034 was displaying fanciful destinations of Kidderminster at the country end and Reading at its London end during afternoon workings on 11 May 2017

Among my own experiences of seeing and travelling aboard Bubble Cars was their use on the twice-daily Gloucester-Leamington Spa service, which plied the route via Cheltenham Racecourse and Broadway, now home to the Gloucestershire & Warwickshire Steam Railway, until its closure to passengers in March 1968.

On their last day with Chiltern (19 May 2017) W55034 operated three early morning round trips from Aylesbury before being unusually paired with W55020, which had finally been repaired in time to handle the large number of extra passengers on that day.

The two units then operated a number of additional late-morning and early afternoon services, the scheduled three evening peak round trips, then one final additional service leaving Aylesbury at 20.08 and returning from Princes Risborough at 20.33.

The Bubble Cars, which have a top speed of 70 mph and are vacuum-braked, have proved remarkably popular in preservation, with most of the class finding a new lease of life, and two (W55023/24) based on the nearby Chinnor & Princes Risborough Railway.

After their retirement from Chiltern W55020 was, rather appropriately, sold to the Bodmin & Wenford Railway in Cornwall (seen above at Bodmin in June 2019), while W55034 was sent to Crewe, where it has now become a route-learning vehicle.