Winter CMEs 2013

A shot to go with Stephens video....... LINK

 

With 46115 scheduled to work the CME on 23rd February which engine will work it on 2nd March as 46115 is working the Cumbrian Guardsman on that date ?

 

If i had have known that was you Stuart I would have said hello ,great shot even though the A4 had shut off . Regards Steve

 

Yes absolutely - it has been superb to see an A4 in top form on the S&C (and Shap) and at this time of year.

 

When your lugging 350/400 tons around anyway, an extra ton or two of coal and air brake piping is a drop in the ocean, fair point on coal quality, but it wasn't always brilliant years ago either, that programme on Welsh railways the other week, the ex driver was saying how they often got the rubbish coal as the best stuff went to Landore for the Paddington turns.

 

No 9 heads away from the gloom
Henry

 

Superb shot henry , light and dark worked so well mate .

 

Defer entirely to your superior knowledge of load dynamics and their effect on acceleration in that case. Thanks and to Ralph W for putting things in perspective as to why extra weight has no marginal effect on performance.

 

Agree with Steve 'H' a lovely colourful shot-still trying to get Trooper clean so thanks for showing me Waitby!!!!

 

Sorry mate but I think your arty farty shot is much superior
Hxx

 

Adding a few hundred pounds of Westinghouse pump and pipework to 500 tons of loco and coaches will make the best part of b*gg*r all difference to how it goes up hill. The extra weight is the difference in probably no more than half a dozen passengers.

What might make rather more difference is whether the train is steam heated or not. Even for a big loco like an A4 or a MN, capable of a sustained 2000hp or so, the amount of steam used in the steam heating will be equivalent to 5- 10% of its output, depending on length of train and how cold it is. So if you want record breaking up hill, go during the summer - or else hope the fireman is canny enough to turn off the heating at the foot of Shap Fell and turn it back on again at the top

Tom

 

The point was that when the "blue riband" times are close small margins make a significant difference, notwithstanding the other more variable elements. Essentially all other things being equal you would expect the lighter loco to be marginally quicker between a and b.

 

Depends more on the power to weight ratio. You also have to consider the adhesion question. It gets more complicated when you consider all the other design factors that dictate the performance of a locomotive. Then there are crewing factors.

I don't believe we have seen the very best that 60009 is capable of achieving. It has always been an interesting performer and we should be grateful to John Cameron for allowing it to be so. But it a preserved engine when all is said and done and as such has nothing to prove unless its owner thinks otherwise.

 

Do the maths. Assume an engine can put out a given power output that remains unchanged, and then see how much slower on, say a 1:100 gradient, adding wight equivalent to perhaps 0.1% of the total train weight will make (assuming a fairly generous 1/2 ton for airbrake equipment in a 500 ton train). It's within the error bars of how much the whole consist weighs anyway. Passengers with their bags probably weigh about 10 or 12 to the ton, so a typical charter with 400 passengers could have at least 30 - 40 tons of humanity on it, as well as all the food they eat, water in the toilets. A slightly poorer than hoped sale of tickets could easily make 3 or 4 tons difference in passengers. The amount of coal in the tender will vary depending whether you hit the bank fresh after coaling or near the end of a run; ditto the water in a tender (which in a Merchant Navy weighs about 26 tons, along with 5 tons of coal - so there is up to 30-odd tons difference there depending on just when in the trip you hit a hill). So even two trips with the same engine and the same carriages could differ by perhaps 35 tons just depending on how stocked the tender, the bar, the toilets and the seats are. In those circumstances, worrying about the impact on performance of the weight of an airpump, resevoir and a few feet of metal tubing is just silly.

Tom

 

In which case the volume of water in the tender would also come in to play. 220 gal of water = 1 tonne, which probably equates to the air brake kit you mentioned earlier.

Oops - didn't spot Jamessquared reply!

 

All thing being equal was the phrase used. Never mind all academic but thanks for the science lessons anyhow, never anticipated praising number nine would cause such a fuss!

 

The interesting point is that the whole "sport" of timing locomotive performance is an entertaining game for enthusiasts if you are that way inclined, but really is a nonsense by time you take in the vagaries of load etc. Two seemingly identical trains with identical carriages could have maybe 5 or 6% difference in real weight, depending on how many passengers and how much coal, water etc is being carried; and could also have perhaps 5 - 10% difference in available power as a result of whether they were steam heating or not. Before you know it, you have a 10% difference in power to weight ratio (which is what gets you up hills), which makes timing a bit silly.

'Twas ever thus: locomotive engineers of old were certainly sufficiently interested in performance to go to the lengths of constructing dynanometer cars (to measure draw par pull vs speed) and taking indicator diagrams (to measure cylinder power and efficiency as a function of speed), and later constructiing static testing stations. But I doubt they ever took much notice to the likes of Nock and Sekon et al leaning out of windows with stopwatches in their hand. I suspect, on the other hand, that their respective publicity departments were secretly more than pleased whenever some startlingly good log was published, though obviously being far too modest to openly boast about such things! Publicity departments like amazing feats; hard bitten operating superintendents tend to prefer what level of performance can be guaranteed day-in, day-out even with locos near to being shopped, long after a washout and with poor coal.

Tom

 

Loco update. : 60009 is now booked for the final 3 CME s and not as previously advised.

they have all sold out.

 

Yippee!! A proper engine. Here's to a cracking run on 2 March. My last A4 on the mainline was "Mallard" in 1988!

With the same engine (60009) covering all of the trips, it would be interesting to compare the timings bearing in mind the different weather conditions. Not sure if a bunch of NatPres moderators on the train would speed things up or slow them down.

Richard