[dwb]

QUOTE Gresley mobilised one of the double chimneyed engines, No 4468 Mallard, to head the 244 tonne test train of dynamometer car and three articulated twin units from a Coronation train set - P44 "The Fastest Trains in the World" by G. Freeman Allen published 1978 ISBN 0 7110 0889 2

Neither Hornby nor Bachmann make the articulated twin units, so all the coaches will have to be kit built. I'm not even sure there is a current kit of these?

David

 

[dwb]

QUOTE The failures occurred on power, or more precisely when high power was being produced.

In the absence of a rolling road it's hard to see how you can test for a condition like that. Finding an empty stretch of mainline to run at maximum power isn't something that happens very often.

David

 

[dwb]

QUOTE I am fairly sure that both Rugby and Swindon had rolling roads, Gresley (I think) consulted André Chapelon to improve the draughting of the A4's but I am not totally sure.

I believe the rolling road at Rugby was at the instigation of Stanier and Gresley but came some time after Mallard's record breaking run.

The Kylchap exhaust fitted to Mallard is a Chapelon design which is where the "chap" in the name comes from. Looking up this Wikiepedia article on Kylchap reveals where the Kyl comes from - a Finn Kylala whose nozzle formed the second of the three stages in the complete exhaust assembly.

David

 

[dwb]

QUOTE tried to persuade Collett of the virtues of a large trapezoidal grate 'Super King' 4-8-0 to supply the GWR

How about trying your hand at one those Andii?

David