Class 86 (BR Doncaster / English Electric AL6)

The Class 86 AL6 was the production class of AC electrics built for the West Coast Main Line following on from the pilot-scheme AL1-5 (Classes 81 to 85). The AL6 took advantage of experience gained from the earlier locomotives including fitting only one pantograph and with changes to equipment though the AL6 was very similar to the Class 85 AL5 except for the stub nose cab ends.

Number built: 100
Built: 1965-66
Builder: BR Doncaster / English Electric
Engine: 4 AEI 282AZ or GEC G412AZ (86/1) traction motors (25kV AC OHLE) 
Power: (86/0) 5, 900 hp (4, 400 kW) max output
Wheel arrangement: Bo-Bo

The AL6 was designed for mixed traffic including travelling up to 100mp/h with WCML expresses. Unfortunately this caused some problems with the original axle-hung traction motors with troublesome riding qualities and damage caused to the track and to bogies. Following research at BR Derby  a "flexicoil" suspension system was adopted for fifty eight of the class which were designated Class 86/2 [1]. Another early sub-class was the 86/1, a trio rebuilt to help develop the follow-on Class 87 and able to reach 110mp/h [2][3].

Another sub-class was the 86/3 which were fitted with SAB resilient wheels and with equipment for multiple-working. The Class 86/4 were fitted with flexicoil suspension and SAB wheels for mixed-traffic. The 86/5 was a trial locomotive to test ways of improving performance on heavy  freights. The 86/6 are a sub-class used on Freightliner trains, finally the 86/9s were a couple of locomotives used as load banks by Network Rail.

Despite their advancing years the Class 86 can still be regularly seen on the network, mostly hauling Freightliner trains though also on some passenger charters (86 259 as shown below has been returned to it's original Electric Blue [4]). Some have also been exported to Eastern Europe.
86 259 heads through Stafford with a railtour

Class 86 in British Rail days (KD Collection)

86 259 at Tyseley

[1] Brian Haresnape, Electric Locomotives (Ian Allan, 1983) p. 64
[2] Gavin Morrison, AC Electric Locomotives in Colour (Ian Allan, 2013) p. 25
[3] Pip Dunn, British Rail Main Line Locomotives Specification Guide (Crowood Press, 2013) p. 161
[4] David Lawrence, British Rail Designed 1948-97 (Ian Allan, 2016) p. 155