The Avro plans show the trolley as a modified Type E, with two rectangular bars (wooden I’d guess) added on the top (parallel to the wheel axles) atop which sat the Upkeep (also axis parallel to the wheel axles). There is a copy of this in Cooper’s “The Men Who Breached the Dams”.

Does anyone have a photo of a Type E trolley? I’ve found some Type F trolley images but it appears to differ from the plans of the type E in several respects.

Many thanks,

Iain.