LMS Record of 114mph

It did dampen enthusiasm. Isn't it reported that afterwards, the LMS and LNER had a gentlemans agreement to stop speed record attempts.

 

Probably not. If they had, 4468 wouldn't have made its attempt in 1938 and had the Austrian Corporal not intervened, HNG wanted a tilt at 130.

 

Outright air speed records had to be set in level flight. If you look at the speed records for virtually any other form of transport then there are regulations to get an official record which equalise the "playing field" . In practice though people still travel the world for the longest and most level dry lake, or the strongest wind with the fewest waves or whatever... And wouldn't it be better to know what the fastest steam locomotive was on level track? Is a Duchess, with extra brute horsepower, and reliable mechanicals slower or faster than an A4 with a more sophisticated front end but (in those days) inadequate big end lubrication? But its impractical. To actually find which was really the faster locomotive on level terms you'd have to ship them all out to the Nullarbor plain in Australia, upgrade 50 or so miles of track to unlimited speed standards - and then find out the German loco was faster on the level anyway...

 

Wasn’t on about air speed records but as you mentioned them, prior to the measured circuit the aircraft would gain speed in a dive and the pull out into level flight for the record attempt.

 

It never ceases to surprise me, the lengths/arguments some people spout to denigrate the 4468 achievement. Mallard holds the world speed record for steam...end of story.

 

Add 10 mph to 6220 on the approach to Crewe and I think bearings would have been the least of the problems the LMS faced that day.

 

Would've saved on even more washing up than for the 114mph run tho'!

 

To be fair aircraft don't tow gliders and cars don't tow caravans on world speed record attempts. If you wanted official regulations for rail speed records would they state light engine only or a particular trailing load, would you include or exclude the weight of the tender in calculating the trailing load, would the load vary by engine weight or by nominal engine power? The train weight has as much influence as the gradient. In the absence of anything better the simple tradition of absolute maximum regardless of gradient or train weight is probably as fair as can be achieved.

I'm sure Mallard was producing much more power than Coronation Scot - and *perhaps* as much as any Duchess has ever achieved.

Regarding the importance of fleeting maximum speeds - we have a proud tradition in this country of taking trivial things very seriously - and there is nothing wrong with that.

Before he travelled on the LMS speed run, C J Allen had already been shaken by the 1934 run of 4472 (flange marks where none should appear) and on the Silver Jubilee run the next year. But the effect on my nerves had been such that when I was asked to go down to Newcastle on the first public run of the Silver Jubilee, three days later, to record the times for Press purposes, I found a convenient excuse of urgent work elsewhere.

 

IIRC the gradient profile for the German record run wasn’t exactly a billiard table.

 

I can't just remember where I read it now, but I have definitely read an article that stated that after the record attempt, there were score marks on some rail chairs, and also scoring on the flanges of 6220, which indicated that the locomotive had actually become derailed, and then re-railed itself. I think it was an issue of Steam Railway several years ago, but I'm not entirely sure. If I ever find it again I will either transcribe it here, or post images of the article.

Richard.

 

http://www.guinnessworldrecords.com/world-records/fastest-caravan-tow

 

I read somewhere that the A4's i.h.p. was in the 3,100 at 126 mph, well short of 6234's near 3350. But all credit to the A4: it achieved what was set out for it.

 

But, at what speed was 6234's output achieved at?
Surely to achieve that output at 126 mph was outstanding.

Dave

 

It's easier to achieve high power at high speed as, by definition, Power = Force (Tractive Effort - at the time, not Nominal) x Velocity (speed). As speed rises into the higher values, the TE falls away and then there's a balance between the rising speed / falling TE. But it's far harder to get a high power output at a low speed than at a high one.

 

I have heard it said that the fireman on Coronations 114mph run was so scared he never went back on the footplate again - and that when the LNER went for the record, Bray was chosen as he was known not to scare easily, if at all.

 

Was Mallard indicated while doing 126 mph?

 

Neither the Stanier nor Gresley engine was indicated. The i.h.p. values were calculations from the Dynamometer car rolls. Not 100% accurate, but certainly a ball park figure, and probably accurate to better than 300 h.p..

 

My understanding is that, as speed rises, reducing cylinder efficiency starts to dominate vs the beneficial effect of the higher speed on power output. For this reason power output will start to fall away above, say, 60 mph. As usual though, I'm happy to be corrected.

Dave

 

What was the drawbar power measured at 126?