INTRO: Richard Hope takes a ride with an innovative multi-purpose piggyback/container wagon designed for the restrictive British loading gauge

A TEST RUN from Derby to Carnforth and back, one of three carried out during February by Serco, provided an opportunity to assess the ride quality at 145 km/h of Babcock Rail’s prototype Mega 3 pocket wagon. During the first run it carried a milk tank trailer full of water at 160 km/h. This was followed by a second run with the tanker empty, and a third with the wagon unloaded.

Babcock’s objective is to secure RIV registration allowing Mega 3 to run at 140 km/h on the continent and at 90mile/h (145 km/h) in Britain. The ride at the higher speed was quite steady, apart from occasional vertical oscillation sufficient to cause the fifth wheel holding the trailer kingpin to unload momentarily when the rails dipped. Vertical displacement of the trailer relative to the wagon due to tyre and bump-stop elasticity never exceeded