Performance of "lumbering" Cl 40s and other early BR diesels

[Cowley]

Really enjoying reading this thread folks.
Just to add a moment in time...
Sometime in spring 1988 behind 47497* leaving Taunton and heading west with 13 on and absolutely staggering up Whiteball - probably topping the bank at about 38mph, we somehow made it, before hurtling down the other side non stop through Tivvy Parkway on the way to Exeter. Even then it seemed surprising to me that a ‘modern’ train could struggle like that...

* 47497 became 47717 within a year.

 

[hexagon789]

Really enjoying reading this thread folks.

Same here, one of the best and most engrossing threads going just now.

 

[edwin_m]

I recall someone telling me of a lively ride down Stoke Bank behind a 31, and at Peterborough the driver came out of the cab with a photo (must have been a Polaroid in those days) of the speedometer showing 100.

 

[hexagon789]

I recall someone telling me of a lively ride down Stoke Bank behind a 31, and at Peterborough the driver came out of the cab with a photo (must have been a Polaroid in those days) of the speedometer showing 100.

Can well imagine it! Sounds like a cracking run.

 

[delt1c]

I came across one from the early 70s with a 55 managing 115 mph in more than one location, another with an 86 touching 111 mph. near Rugby....those were the days!

Remember that Deltic arriving at Crewewhen on hire to Virgin , came in like an emu and left like one as well.

 

[hexagon789]

Remember that Deltic arriving at Crewewhen on hire to Virgin , came in like an emu and left like one as well.

Is that the one that did the Ramsgate XC services in about 2002/3-ish?

 

[Ash Bridge]

Remember that Deltic arriving at Crewewhen on hire to Virgin , came in like an emu and left like one as well.

I sure do, and I would dearly love to see a P&P log of its journey to/from Glasgow Central that weekend, even just the bit between Crewe, Stafford and Brum that we covered.

Is that the one that did the Ramsgate XC services in about 2002/3-ish?

No on this occasion Virgin XC employed it on a Birmingham-Glasgow leg up the WCML on the Friday, and returning south as far as Brum on the Saturday, apart from the exhaust haze drifting back you would have thought there was an 87 or 90 on the front!

 

[hexagon789]

I sure do, and I would dearly love to see a P&P log of its journey to/from Glasgow Central that weekend, even just the bit between Crewe, Stafford and Brum that we covered.


No on this occasion Virgin XC employed it on a Birmingham-Glasgow leg up the WCML on the Friday, and returning south as far as Brum on the Saturday, apart from the exhaust haze drifting back you would have thought there was an 87 or 90 on the front!

Would have loved to travel on that.

 

[hexagon789]

The trouble with this thread is it'still making me jealous of the cracking runs people are describing!

 

[gazthomas]

The trouble with this thread is it'still making me jealous of the cracking runs people are describing!

If that's sparked an interest have a look at the Railway Performance Society website: http://www.railperf.org.uk

 

[hexagon789]

If that's sparked an interest have a look at the Railway Performance Society website: http://www.railperf.org.uk

Cheers, looks interesting. I'm quite a fan of the timing logs found in several railway publications, so this shold prove most interesting.

Thank you

 

[gazthomas]

Cheers, looks interesting. I'm quite a fan of the timing logs found in several railway publications, so this shold prove most interesting.

Thank you

I'm glad you like. I enjoy reading articles in both Railway Magazine and Rail Express. The author in the latter makes me laugh - a Neville Hill! (Leeds depot) This is either an amazing coincidence or a joke!

 

[hexagon789]

I'm glad you like. I enjoy reading articles in both Railway Magazine and Rail Express. The author in the latter makes me laugh - a Neville Hill! (Leeds depot) This is either an amazing coincidence or a joke!

I also enjoy the ones in Steam Magazine, the records of a by-gone age.

I wonder if Neville Hill is his name or a deliberate play on the Depot, it is like you say an interesting coincidence!

 

[Bevan Price]

I also enjoy the ones in Steam Magazine, the records of a by-gone age.

I wonder if Neville Hill is his name or a deliberate play on the Depot, it is like you say an interesting coincidence!

He is a real person but I won't name him here. He is now retired, and has many years' experience of recording performance.

 

[hexagon789]

He is a real person but I won't name him here. He is now retired, and has many years' experience of recording performance.

Good to know, his logs were always a highlight in the mag.

 

[fowler9]

Just wanted to ad that I am also loving this thread. Many thanks for all the info. From memory I always felt the Peaks and Whistlers etc. were a little pedestrian. I always preferred them to Spoons though. Ha ha. A bit more interesting to me at least.

 

[hexagon789]

Just wanted to ad that I am also loving this thread. Many thanks for all the info. From memory I always felt the Peaks and Whistlers etc. were a little pedestrian. I always preferred them to Spoons though. Ha ha. A bit more interesting to me at least.

I've never had the pleasure of hearing a Whistler or Peak, but I adore the throaty rumble of a Duff or the hearty growl of a Tractor.

 

[Flying Phil]

Back in the late 60's my father and I went to the ECML near Essendine, to see the newly preserved "Flying Scotsman" on a tour. We got chatting to a signalman as a Deltic went past at a rate of knots. The signalman said that they sometimes cracked the 2 mile section in around a minute! Obviously annecdotal and approximate but they certainly sounded great and really flew down the bank!

 

[JohnR]

I was thinking back to the D200 tour in 1987 that went Exeter, can you remember what sort speed it topped Honiton Bank at?
They used to have some quite long trains on those tours.

It would be interesting to compare that with the performance of 10203 over the same route in the 50s. The ACE was loaded to 13 usually.

 

[Cowley]

It would be interesting to compare that with the performance of 10203 over the same route in the 50s. The ACE was loaded to 13 usually.

It would be wouldn’t it. Would the ACE have stopped at Seaton Junction to drop a coach off? In my mind I’d always assumed that it would be non stop through there (and Crewkerne) and thus able to take a full speed run at the bank?

 

[AndrewE]

Anyway, TE is not what this thread is about. But if you want to bring that in because Class 40s had a lot of it, and put it to good use, with examples, ....... feel free to do so. But speed has its merits, or the LNER would not have nearly bust an expensive locomotive in a successful attempt to reach 126 mph.

I think we forget the characteristics of the locos that preceded diesels and what people were used to. Starting off, steam can be applied at full boiler pressure to the pistons throughout their travel (within the limits of the adhesion), so locos were very good at moving heavy trains at slow speeds. Look at the 9F pulling 2000 Tonnes at the ESR.
I'm always amazed at the huge old freight trains that used to lumber around in the care of one relatively small steam engine. Electric traction motors cannot be used at full power in these circumstances as the lack of back-EMF means they overheat rapidly. Electric transmission is excellent for continuing to supply power when running fast though, which steam is not so good at.
Hence both the apparent disappointment at low initial acceleration of diesels and the delight at the much higher speeds of new traction up and over the tops of banks. And the facts that a) modern passenger trains like Pendolinos are relatively light weight (compared to Mk 1s for example) and b) we don't really expect them to drop to a crawl on Shap or Beattock.

 

[JohnR]

It would be wouldn’t it. Would the ACE have stopped at Seaton Junction to drop a coach off? In my mind I’d always assumed that it would be non stop through there (and Crewkerne) and thus able to take a full speed run at the bank?

Non-stop Salisbury - Sidmouth Junction usually. Drops one off at Salisbury, 2 at Sidmouth Junciton (for Sidmouth and Exmouth) then drops 2-car restaurant cars in Exeter Central where it divided into North Devon and Plymouth/North Cornwall portions (usually with some coaches added at central). Some of the relief portions of the ACE on summer Saturdays may have stopped at Seaton Junction (or Axminster for Lyme Regis), but I cant recall.

 

[Cowley]

Non-stop Salisbury - Sidmouth Junction usually. Drops one off at Salisbury, 2 at Sidmouth Junciton (for Sidmouth and Exmouth) then drops 2-car restaurant cars in Exeter Central where it divided into North Devon and Plymouth/North Cornwall portions (usually with some coaches added at central). Some of the relief portions of the ACE on summer Saturdays may have stopped at Seaton Junction (or Axminster for Lyme Regis), but I cant recall.

Thanks for that.

 

[edwin_m]

I think we forget the characteristics of the locos that preceded diesels and what people were used to. Starting off, steam can be applied at full boiler pressure to the pistons throughout their travel (within the limits of the adhesion), so locos were very good at moving heavy trains at slow speeds. Look at the 9F pulling 2000 Tonnes at the ESR.
I'm always amazed at the huge old freight trains that used to lumber around in the care of one relatively small steam engine. Electric traction motors cannot be used at full power in these circumstances as the lack of back-EMF means they overheat rapidly. Electric transmission is excellent for continuing to supply power when running fast though, which steam is not so good at.
Hence both the apparent disappointment at low initial acceleration of diesels and the delight at the much higher speeds of new traction up and over the tops of banks. And the facts that a) modern passenger trains like Pendolinos are relatively light weight (compared to Mk 1s for example) and b) we don't really expect them to drop to a crawl on Shap or Beattock.

Power is irrelevant at low speed due to adhesion limitations (in fact the power being used on starting is zero, because power is force multiplied by speed). The use of full steam when starting a steam engine will often just spin the wheels. Diesels and electrics also suffer from this and it is less obvious to the driver, so there is usually some kind of automatic system to reduce the torque if spin is detected. The motor and gearing ought to be designed so that the maximum tractive effort is comparable to what is achievable under normal adhesion conditions.

Extra power counts more at high speed and for hill-climbing. Hence a low-powered engine can shift quite a long train slowly, especially if it gets assistance on the more severe climbs. An electric could do the same, with the possible exception of the older DC types which can't run indefinitely at low speed because the traction resistances would still be in circuit and would overheat.

 

[30907]

Non-stop Salisbury - Sidmouth Junction usually. Drops one off at Salisbury, 2 at Sidmouth Junciton (for Sidmouth and Exmouth) then drops 2-car restaurant cars in Exeter Central where it divided into North Devon and Plymouth/North Cornwall portions (usually with some coaches added at central). Some of the relief portions of the ACE on summer Saturdays may have stopped at Seaton Junction (or Axminster for Lyme Regis), but I cant recall.

The Salisbury coach went forward on the Exeter stopper, and at various times ended at Seaton, Lyme or Central. Summer Saturdays Seaton and Lyme had their own train in the ACE sequence at 10.45 but it wasn't labelled ACE for good geographical reasons.

 

[hexagon789]

Non-stop Salisbury - Sidmouth Junction usually. Drops one off at Salisbury, 2 at Sidmouth Junciton (for Sidmouth and Exmouth) then drops 2-car restaurant cars in Exeter Central where it divided into North Devon and Plymouth/North Cornwall portions (usually with some coaches added at central). Some of the relief portions of the ACE on summer Saturdays may have stopped at Seaton Junction (or Axminster for Lyme Regis), but I cant recall.

Cheers, good explanation, thanks

 

[Ash Bridge]

I've dug out some more logs as they may be of interest, but I'll make these the last for now because I'm worried it'll be getting just a little bit tedious for some here

Anyway the first features a ton up class 52 from Westbury to Paddington, not a bad effort for 90 mph. locomotive, and the second details four Western runs between Taunton and Exeter, definitely showing their superiority over a class 47 at Whiteball I think? The last two show just how capable the Hymek Class 35s were in their time, I imagine a class 40 would struggle to match that performance on the Newton Abbot to Paddington excursion working, loaded with thirteen bogies?

 

[hexagon789]

I've dug out some more logs as they may be of interest, but I'll make these the last for now because I'm worried it'll be getting just a little bit tedious for some here

Anyway the first features a ton up class 52 from Westbury to Paddington, not a bad effort for 90 mph. locomotive, and the second details four Western runs between Taunton and Exeter, definitely showing their superiority over a class 47 at Whiteball I think? The last two show just how capable the Hymek Class 35s were in their time, I imagine a class 40 would struggle to match that performance on the Newton Abbot to Paddington excursion working, loaded with thirteen bogies?

Some cracking logs there. I think the Westerns were perfectly capable engines but I've read that the transmission wasn't ideally suited to the engines (can't render exactly) and that when well run in they could often struggle to achieve their 90 mph rating.

 

[Ash Bridge]

Some cracking logs there. I think the Westerns were perfectly capable engines but I've read that the transmission wasn't ideally suited to the engines (can't render exactly) and that when well run in they could often struggle to achieve their 90 mph rating.

Although Western Reliance was clearly in good fettle there peaking at 102 mph. passing Southall.

 

[hexagon789]

Although Western Reliance was clearly in good fettle there peaking at 102 mph. passing Southall.

Very fine fettle, I did see a record in I believe the Railway Magazine where a Western managed 104 and about 99-102 for a good 10 miles.