[QUOTE=WHBM]This is not quite correct. The 1955 tests (2 trains on consecutive days) were done on the dead-straight line from Bordeaux towards the Spanish border, so no curving issues. The only problem was the overhead electricity wiring. This was known to be the weak point and the wire was specially greased, unfortunately the ensuing smoke spoiled the film record being made from a cine camera on the locomotive roof of the wire and locomotive collector.


La Vie du Rail clearly states (albeit in translation - I haven't seen the original article) the trackbed was badly damaged, and that's logical. For very high speeds the ties have to be more numerous per kilometer, the rail heavier, the cant varied, the ballast deepened, the rails more tightly fastened to the ties, etc., to prevent rail displacement. All this came out of the 1955 tests (on the Bordeaux line? Thanks for the detail. The 1990 tests were on the Atlantique line around Vendome before the lines was opened to general traffic) and was incorporated into the construction of the Atlantique line.