Talk:LNER Peppercorn Class A2

Latest comment: 16 years ago by ChrisRed in topic Regulator Jammed Open?

CME succession

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Arthur Peppercorn succeeded Edward Thompson and not Sir Nigel Gresley as CME of the LNER. I have made a minor change to reflect this. --LieLestoSbrat 18:56, 1 May 2006 (UTC)Reply

Regulator Jammed Open?

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This one keeps recurring. Somehow the presence of water in Blue Peter's regulator valve is supposed to have jammed it open. I remember reading an interim report after the incident, and this suggested that the driver had actually succeeded in shutting the regulator quite early in the slip (hence the wheelslip easing in ferocity for a few moments before then going catastrophic). Unfortunately the loco had already primed heavily, and several gallons of hot water then entered the superheater where it vapourised and expanded directly from water to superheated steam. Now that the regulator was shut, the resulting trapped steam had only one way to go - out through the cylinders. It's no wonder that the poor man couldn't wind the gear back - God knows what pressure the trapped steam reached before the 'prime' boiled-off. If the regulator had been left open, the rest of the boiler would have followed it out through the cylinders, instead of lifting the safety valves as seen in the video. ChrisRed (talk) 14:50, 7 July 2008 (UTC)Reply