British Rail Class 28

The British Rail Class 28, originally known as Metropolitan-Vickers Type 2, diesel locomotives were built as part of the British Railways Modernisation Plan.  The locomotives had a Co-Bo wheel arrangement. There was a 6-wheel bogie at one end a 4-wheel bogie at the other end. This wheel arrangement was unique in British Railways practice but not uncommon in some other countries, notably Japan. This affected their route availability, due to the different axle loading at each end of the loco, and made maintenance more complicated.  The maximum tractive effort  was unusually high for a Type 2 locomotive but, as there were five (not four) driving axles, the risk of wheelslip was minimal.

Preservation
D5705 is the sole survivor, now preserved at the East Lancashire Railway.

In Fiction
In the popular British children's TV show Thomas & Friends, A character by the name of BoCo is based on this class, his name probably due to the fact of the name of the Whyte notation given to this class, mentioned above, 'Co-Bo'

References

28