8 MPH Speed

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Ploughman

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I was just reminded of the 8 mph speed at London Kings Cross
It has often puzzled me as why this odd figure was chosen.

I was always told when designing that all railway speeds should be rounded to the nearest 5 below. So why this oddity?

Anyone know of any other odd figures not to the nearest 5 mph?
 
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John Webb

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I was just reminded of the 8 mph speed at KC.
It has often puzzled me as why this odd figure was chosen.

I was always told when designing that all railway speeds should be rounded to the nearest 5 below. So why this oddity?

Anyone know of any other odd figures not to the nearest 5 mph?
At St Albans South signal box we have a 12 mph sign on display, which we understand is quite unusual.
 

LE Greys

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Remember it was set up at a time when most locos didn't have speedometers. They probably went for "double walking pace" in the hope that drivers could judge that accurately. Flying Scotsman nearly derailed when leaving Platform 9 on her record run to Leeds, they apparently found flange marks in some very unusual places.
 

MK Tom

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Where I work the site speed limits are 9mph & 19mph. Management reckon odd speed limits like this will make people more aware and not exceed them....

Yeh... right...
19mph limits have been used on roads when people had thought metrication was imminent. I don't know if that applies to rail too though.
 

NIMBUS

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I was just reminded of the 8 mph speed at London Kings Cross
It has often puzzled me as why this odd figure was chosen.
It's 5 mph at the KX end of Gasworks Tunnel, under the Regent's Canal, so perhaps another 3 mph was all that was realistically calculated to be possible in either direction between the platforms and the mouth of the tunnel?
 

Dieseldriver

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Theres a bridge structure between Neasden and Finchley Road southbound on the Metropolitan line which is (IIRC) 18mph for engineers trains.
 

tirphil

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MGR loops at Drax are 3mph and are signed as such. Takes a while to get around, frustrating when you're not actually unloading coal.
Have the line speeds been revised down? Used to be 5mph on all lines except 3mph over the weigh bridges and 0.5mph or 1mph through the hopper house (depending on wagon type). Propelling from the FGD (Gypsum, limestone, flyash) was restricted to 3mph.
 
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