0–60!: CLASS 720
Just how nimble are today's locos and units, and what's the quickest off the mark?
Our regular performance column puts Greater Anglia's new Bombardier (now Alstom) five-car AC electrics through their paces on the Great Eastern Main Line.
Having previously experienced the abilities of new Stadler units in East Anglia, our performance expert John Heaton FCILT * returns to the region to sample the latest Bombardier Class 720 Aventras in full flight.
NO apologies for a return visit to Liverpool Street. The investment by Greater Anglia in new units as a means of securing the franchise under the now officially discredited old system might not work under the Great British Railways regime, but at least the residents on the Norwich and Cambridge lines have new trains.
Whether ‘new' means ‘better' depends on what value you place on comfort, but the seating layout of Bombardier's Class 720 Aventras (designed before the manufacturer's takeover by Alstom) does nothing for the concept of distancing, social or otherwise. On the other hand, performance is undoubtedly better on the Colchester Town and Clactonon-Sea services than the displaced Class 321s.
The best section for a level start on the Norwich main line is westbound from Kelvedon – absolutely level for nearly two miles, by which time modern AC EMUs can be doing 100mph.
On a recent visit to Colchester, accompanied by Railway Performance Society publicity officer and Greater Anglia guru Baard Covington, we initially had a driver who put fuel conservation ahead of precise timekeeping, but we were more fortunate on the return leg – although a sharp run from the Kelvedon stop managed to beat the net timing by only two seconds. However, the section to Witham has one minute recovery time added which, at least in this case, did not mitigate against fast acceleration.
The proposed 10-car Class 720s were supposed to be over 10% lighter than 2x5-cars, which in turn are 10% lighter than 3x4-car Class 321s for a similar number of seats. But as the franchisee last year plumped for an all five-car fleet, we'll forever be denied the chance to determine the enhanced performance of a 10-car set. With the same proportion of power provision it would, in theory, have beaten the recorded 2x5-car 43 seconds time, which in turn is thought to be just a shade slower than their full capabilities.