No Deltic speed record?

[CTS1990]

I had a fantastic morning at the DPS shed at Barrow Hill yesterday. Spoke to a very knowledgeable member who mentioned there was never a speed record run arranged for the 55s.

Interesting that the A4s, HSTs and 91s were tested to their limits...but nothing official for the Deltics?

I imagine there were plenty of unofficial runs, presumably they were more than capable of 110mph+

 

[Sun Chariot]

The backdrop to 4468 "Mallard" was to capture the lucrative consumer market along the Anglo Scottish corridor; plus an inherent inter-company rivalry between LNER and LMS.
This linked page provides insught - section Heyday of the A4: the 1930s.

LNER Encyclopedia: The Gresley A4 Pacifics

Describes the streamlined Gresley A4 Pacifics

www.lner.info

HST, Electra (91) and APT runs were driven by BRB's publicity machine to, I understand, bring public interest (and revenue) back to the railways' principle intercity routes.
This was the era of high car-ownershp, a mature network of motorways and several years of an "under-funded, unreliable, uncompetitive" tarnished image for BR.

The Deltics were introduced as a squadron fleet intended to  consistently reduce journey times - the focus (and publicity) was that, rather than absolute speed or a "one off" record.
There was no "trunk road" network, so driving long distances still took far longer than rail travel; but car ownership (and its convenience) was on the increase.
The railway infrastructure was making good its recovery from the austerity period's overdue maintenance, so train timings could finally eclipse those of 1935-1939.
Gresley Pacifics were reaching their point where replacement on front-line services would be necessary. Some A4s though had a final fling until 1966, on the 3-hour expresses between Glasgow Buchanan Street and Aberdeen

 

[edwin_m]

HST, Electra (91) and APT runs were driven by BRB's publicity machine to, I understand, bring public interest (and revenue) back to the railways' principle intercity routes.
This was the era of high car-ownershp, a mature network of motorways and several years of an "under-funded, unreliable, uncompetitive" tarnished image for BR.

The Deltics were introduced as a squadron fleet intended to  consitently reduce journey times - the focus was that, rather than about absolute "one off" speed record.

I don't really see the difference here. Both the HSTs and the Deltics were about facing up to competition from cars, albeit in different eras when the speed needed to do so was also different. The HST was also more consistently used than the Deltic, as it spread to all the main non-electrified intercity routes. The change from the HST to the IC225 fleet was much less transformative in reduced journey times than the earlier one from Deltics to HSTs. So it's not clear to me why the Deltics didn't get a run at a speed record for publicity purposes too.

 

[Trackman]

I had a fantastic morning at the DPS shed at Barrow Hill yesterday. Spoke to a very knowledgeable member who mentioned there was never a speed record run arranged for the 55s.

Well, there was, soft of...

https://www.delticsounds.com/deltichowfast.html

The fastest run that I know of (that is believable!), was written up in "Railway World" magazine many years after the event took place back in 1978. Unfortunately I've lost track of the magazine issue and so can't quote the reference. The locomotive was 55008 "The Green Howards", and the 'event' was the retirement of a driver. This was very much an unofficial event! It was carefully planned so that a Deltic was available with excellent running gear, and wheels at maximum diameter. What is more, this was a normal scheduled service train with passengers, 10 coaches load, rather than a light-weight test or empty working.

The service was from Newcastle to Kings Cross and speeds above 110mph were recorded prior to the descent of Stoke Bank. There, the maximum was recorded as 125mph. Whether or not the driver switched off the ETH to gain a little extra power, I don't know! With a lighter load, and if the traction-motors held out, then unloading would probably prevent anything much above 130mph. However, I would not recommend experimenting! Tests of speeds ascending gradients are a more interesting - and safe - challenge.

 

[norbitonflyer]

I did read of a run with the prototype descending Shap when the armature banding on all six traction motors burst through overspeeding, and it was suggested that it would have taken a speed of 130mph-plus to acheive that.

Passage related in "The Deltic - A symposium" published by Ian Allen 1972 - page 11.
An interesting book, long out of print, co-authored by Roger Ford (3 chapters, including the one in which this incident is related), GF Fiennes, Brian Haresnape, Brian Perren and Cecil J Allen

EDIT - I see that the incident is also mentioned in the link in "Trackman's" post, although that gives no estimated speed. Of course the production Deltics were not identical, and may have had stronger (or less strong) armature banding.

 

[Sun Chariot]

So it's not clear to me why the Deltics didn't get a run at a speed record for publicity purposes too.

Wasn't a decent speed clocked up during DP1 DELTIC's time on the ECML. Proving the viability of the traction to BR(ER)'s operating division and the public alike? Admittedly, not a UK speed record attempt.

 

[12LDA28C]

I did read of a run with the prototype descending Shap when the armature banding on all six traction motors burst through overspeeding, and it was suggested that it would have taken a speed of 130mph-plus to acheive that.

Passage related in "The Deltic - A symposium" published by Ian Allen 1972 - page 11.
An interesting book, long out of print, co-authored by Roger Ford (3 chapters, including the one in which this incident is related), GF Fiennes, Brian Haresnape, Brian Perren and Cecil J Allen

EDIT - I see that the incident is also mentioned in the link in "Trackman's" post, although that gives no estimated speed. Of course the production Deltics were not identical, and may have had stronger (or less strong) armature banding.

You may be interested to learn that 'The Deltics - A Symposium' was republished in 1977 as a second 'revised' edition with updated information included. I managed to pick up a copy a few months ago for four quid.

 

[Magdalia]

You may be interested to learn that 'The Deltics - A Symposium' was republished in 1977 as a second 'revised' edition with updated information included. I managed to pick up a copy a few months ago for four quid.

I've been swindled, my copy was £5!

The final chapter is on Deltic Performance. In the first edition this was written by Cecil J Allen, the second edition was revised after his death.

It refers to a test run from Newcastle with MarkIIA coaches in 1967 with maximum speeds of 110mph at Little Bytham and 108mph at Tempsford (pages 66-67).

 

[Helvellyn]

Deltics, Clactons and REPs - would have been interesting to see what all three could have achieved if there had been official speed runs.

 

[Clarence Yard]

According to a well respected ER engineer, the traction motors used to hum a bit if you got a production Deltic up to 120mph! The trip he was referring to was a LE test run.

My fastest run (on a production loco) was 110mph. It was on a normal service train and there was nothing untoward happening on the loco itself.

 

[12LDA28C]

According to a well respected ER engineer, the traction motors used to hum a bit if you got a production Deltic up to 120mph! The trip he was referring to was a LE test run.

I'm not sure a light engine should be travelling at anywhere near 120mph, test run or not!

 

[edwin_m]

I'm not sure a light engine should be travelling at anywhere near 120mph, test run or not!

Treble blocking to allow for reduced braking?

 

[3RDGEN]

I suspect BR wouldn't have wanted to try an high speed run since they could have look stupid when it failed to beat the long achieved steam record of 126mph, the world diesel record at that time was at a similar level but had been set years previous.

110mph was reported as common place, an engineer told me they would chase poorly HST's on yellows, maybe 120mph down Stoke Bank but beyond that I doubt. It was the infrastructure upgrades for HST's and shorter train formations that allowed the faster timings and some record start to stop timings been made.

 

[Richard Scott]

I suspect BR wouldn't have wanted to try an high speed run since they could have look stupid when it failed to beat the long achieved steam record of 126mph, the world diesel record at that time was at a similar level but had been set years previous.

110mph was reported as common place, an engineer told me they would chase poorly HST's on yellows, maybe 120mph down Stoke Bank but beyond that I doubt. It was the infrastructure upgrades for HST's and shorter train formations that allowed the faster timings and some record start to stop timings been made.

Would imagine 110mph was easy, 50s used to get well over 110mph so Deltic with extra power (albeit with same traction motors, I believe) should easily achieve that. Suppose it depends on the speed that the generators start to unload as to theoretical top speed of each class?

 

[The exile]

Couple of observations - a meaningful high speed run also requires coaches known to be capable of that speed. Also, for years prior to HST introduction the ECML was riddled with engineering works for the HSTs.
Also, I would imagine that for quite a while after the 2nd Morpeth incident, over speeding would not have gone down well.

 

[hexagon789]

Would imagine 110mph was easy, 50s used to get well over 110mph so Deltic with extra power (albeit with same traction motors, I believe) should easily achieve that. Suppose it depends on the speed that the generators start to unload as to theoretical top speed of each class?

Both geared for 106mph but 50s do unload at a lower speed than Deltics - 87mph for a 50 and 100mph for a Deltic.

Deltics are also some 18 tons lighter as well as more powerful.

 

[Harvester]

There is an interesting article in this month’s Railway Magazine on the ‘Pennine Peak’ rail tour, hauled by 45118 from Liverpool to Newcastle on 8th November. The York-Newcastle leg was completed in 60min 29 sec start to stop, and the author states he could not find a faster start to stop diesel hauled run over this section recorded in the RPS archive. This surprisingly beats the previous fastest in the archive of 61min 36sec, set by Deltic ‘Ballymoss’ in 1975. There was a 47/7 on the rear of the special but it was only supplying heat (not pushing!), but surely a Deltic must have been recorded, running York to Newcastle start to stop faster (maybe even under 60 mins)?

 

[12LDA28C]

There is an interesting article in this month’s Railway Magazine on the ‘Pennine Peak’ rail tour, hauled by 45118 from Liverpool to Newcastle on 8th November. The York-Newcastle leg was completed in 60min 29 sec start to stop, and the author states he could not find a faster start to stop diesel hauled run over this section recorded in the RPS archive. This surprisingly beats the previous fastest in the archive of 61min 36sec, set by Deltic ‘Ballymoss’ in 1975. There was a 47/7 on the rear of the special but it was only supplying heat (not pushing!), but surely a Deltic must have been recorded, running York to Newcastle start to stop faster (maybe even under 60 mins)?

That's an average speed of only 80mph which doesn't seem particularly fast to me.

 

[Richard Scott]

Both geared for 106mph but 50s do unload at a lower speed than Deltics - 87mph for a 50 and 100mph for a Deltic.

Deltics are also some 18 tons lighter as well as more powerful.

Thanks for info, I thought 50s unloaded in high 80s mph so now confirmed. Had no idea on Deltics.

 

[hexagon789]

Thanks for info, I thought 50s unloaded in high 80s mph so now confirmed. Had no idea on Deltics.

The locomotive diagram books give unloading speeds for diesel-eletric classes among other details; copies of a few issues can be found on the Barrowmore Model Railway Group's website, along with many other interesting BR documents for anyone interested.