IET running on diesel

[Bikeman78]

The 1848 Paddington to Swansea ran on diesel power throughout today. I was pleasantly surprised that it kept to time. The delay at Reading was down to the signal before the station being slow to clear; nothing to do with the train. Top speed Reading to Swindon was 118 mph and Swindon to Parkway only 112 mph. 1 hour 53 to Cardiff which coincidentally is the same as my fastest recorded HST runs.

 

[Master29]

The 1848 Paddington to Swansea ran on diesel power throughout today. I was pleasantly surprised that it kept to time. The delay at Reading was down to the signal before the station being slow to clear; nothing to do with the train. Top speed Reading to Swindon was 118 mph and Swindon to Parkway only 112 mph. 1 hour 53 to Cardiff which coincidentally is the same as my fastest recorded HST runs.

Did it do the full 125 between Paddington and Reading? I suspect it probably did considering how well it kept time. Looking at it (1B30) on Realtime trains it kept impressive time throughout with all it's stops.

 

[Horizon22]

The 1848 Paddington to Swansea ran on diesel power throughout today. I was pleasantly surprised that it kept to time. The delay at Reading was down to the signal before the station being slow to clear; nothing to do with the train. Top speed Reading to Swindon was 118 mph and Swindon to Parkway only 112 mph. 1 hour 53 to Cardiff which coincidentally is the same as my fastest recorded HST runs.

Yes they keep very good time under diesel only. There's normally a few running around in service diesel only on a daily basis with no discernible performance impact.

 

[Bikeman78]

Did it do the full 125 between Paddington and Reading? I suspect it probably did considering how well it kept time. Looking at it (1B30) on Realtime trains it kept impressive time throughout with all it's stops.

No idea to be honest. I only switched on the GPS after Reading. In my experience they rarely get over 120 mph on diesel.

 

[philthetube]

Can we assume that this was done because of a defect and not because of other reasons?

 

[JN114]

Can we assume that this was done because of a defect and not because of other reasons?

For an entire journey it’d be safe to presume it’s a unit rather than infrastructure issue.

 

[DannyMich2018]

It's not surprising it kept to time as I believe most services having the same timings as they did when they were HSTs.

 

[221129]

It's not surprising it kept to time as I believe most services having the same timings as they did when they were HSTs.

Wasn't that changed last year.

 

[JN114]

They tightened up timetable in December 2019 to IET timings; HST wouldn’t be able to keep time anymore

 

[Bikeman78]

They tightened up timetable in December 2019 to IET timings; HST wouldn’t be able to keep time anymore

I think they'd just about manage to keep the Swansea schedules. Typically five to seven minutes faster to Cardiff now but the HSTs used to wait time for several minutes at Bristol Parkway, typically arriving at XX02 and departing at XX09 once the Voyager crossed in front of it.

Have the 800s been uprated? During the changeover period they were usually slower than the HSTs, I mean in terms of point to point timings rather than maximum speed. Of course the drivers will be more familiar with them now which will make a difference.

 

[JN114]

I think they'd just about manage to keep the Swansea schedules. Typically five to seven minutes faster to Cardiff now but the HSTs used to wait time for several minutes at Bristol Parkway, typically arriving at XX02 and departing at XX09 once the Voyager crossed in front of it.

Have the 800s been uprated? During the changeover period they were usually slower than the HSTs, I mean in terms of point to point timings rather than maximum speed. Of course the drivers will be more familiar with them now which will make a difference.

Comparing pre-2019 (2015 as it's the WTT I have to hand) 1142 Paddington Swansea with current-day 1148 Paddington to Swansea

In 2015 the 1142 was timed 2h06m to Cardiff
In 2021 the 1148 is timed 1h53½m to Cardiff

Same calling pattern, similar dwells (3m total longer dwell across the 2015 schedule as far as Cardiff)

Even if you excused 5 minutes at Bristol Parkway for that regulation against the Northbound Voyager (which isn't allowed for in the WTT) we're still talking 4-5 minutes difference.

On diesel, yes HST and IET performance is similar – this isn't a coincidence, it was intentional; as such they're pretty evenly matched Cardiff to Swansea, IET makes up ground by being able to achieve shorter dwells. But an HST couldn't keep to IET electric timings; heck it would barely keep to the timings the 110mph Bristol Parkway 387s achieve. We're talking 2-3m faster Paddington to Reading, another 2-3m Reading to Swindon, another minute to Bristol Parkway. Yes, a top driver, engine fresh off exam and hard driving might come close – but you could do such astonishing antics with the IET as well and beat the timetabled times by some margin; as has been proven on various "speed runs" since IET introduction.

 

[DanNCL]

80x units running on diesel don't normally keep to time on the ECML, and that's with many schedules still running on Class 91+Mark 4 sectional running times. When I recorded it on a TPE 802, the maximum speed the unit reached on diesel between York and Darlington was 112 mph, sufficient to keep to Class 185 timings used previously but not sufficient to keep to 80x on electric sectional running times, which all TPE services to/from Newcastle now use North of York.

On the occasions where I've had an LNER unit on diesel under the wires I've never checked the speed, but on each occasion the unit has lost time between each calling point.

 

[Mogz]

These things have no problem doing 125 on diesel. I’m on one now that’s doing 124 according to my speedo app!

 

[Dai Corner]

These things have no problem doing 125 on diesel. I’m on one now that’s doing 124 according to my speedo app!

How long did it take to get to that speed, compared to how long it would have taken on the juice?

 

[TheBigD]

Slightly off topic, but on a recent journey from Penzance to Paddington the guard announced that our train was on reduced power, only 4 engines instead of 5, and would lose time.
Whilst I know the IETs are not known for being sprightly over the devon banks I was surprised that it lost 25 minutes to Exeter, the section between Plymouth and Newton Abbott seemed painfully slow. Lost another 10 minutes between Exeter and Paddington.

 

[Master29]

Slightly off topic, but on a recent journey from Penzance to Paddington the guard announced that our train was on reduced power, only 4 engines instead of 5, and would lose time.
Whilst I know the IETs are not known for being sprightly over the devon banks I was surprised that it lost 25 minutes to Exeter, the section between Plymouth and Newton Abbott seemed painfully slow. Lost another 10 minutes between Exeter and Paddington.

As you point out. The extra engine down would make a huge difference in Devon and Cornwall. The extra 10 minutes post Exeter seems odd unless it ran on diesel the whole journey.

 

[supervc-10]

It may have lost its path though contributing to the delay I suppose?

 

[Wyrleybart]

These things have no problem doing 125 on diesel. I’m on one now that’s doing 124 according to my speedo app!

Is the 124mph thing due to the speed control in the cab ? Think I read somewhere that 200kmh equals 124mph, and that is their maximum. Perhaps "JN114" can confirm please ? Thanks

 

[hexagon789]

Is the 124mph thing due to the speed control in the cab ? Think I read somewhere that 200kmh equals 124mph, and that is their maximum. Perhaps "JN114" can confirm please ? Thanks

Well, that can do a good but more than 125mph, as proved by TPE a while back! But yes, as I understand it the speedset works in km/h and then presumably converts to/from mph (or is set up with preset conversions) and 125mph so is taken as a round 200km/h although it is actually 124mph.

 

[JN114]

Is the 124mph thing due to the speed control in the cab ? Think I read somewhere that 200kmh equals 124mph, and that is their maximum. Perhaps "JN114" can confirm please ? Thanks

I don’t know how it works in the background, no.

The driver sets the speed limiter in miles per hour, whether there’s some conversion going on in the background who knows?

I wouldn’t begin to presume from a readout on a phone GPS how the train was being driven.

 

[Wyrleybart]

I don’t know how it works in the background, no.

The driver sets the speed limiter in miles per hour, whether there’s some conversion going on in the background who knows?

I wouldn’t begin to presume from a readout on a phone GPS how the train was being driven.

Haha yes. I rather agree with you about "assessing" the driver using a GPS device.

 

[Horizon22]

Haha yes. I rather agree with you about "assessing" the driver using a GPS device.

Would also question the complete accuracy from an app you can download on your phone versus a speedometer built into a modern train cab.

Slightly off topic, but on a recent journey from Penzance to Paddington the guard announced that our train was on reduced power, only 4 engines instead of 5, and would lose time.
Whilst I know the IETs are not known for being sprightly over the devon banks I was surprised that it lost 25 minutes to Exeter, the section between Plymouth and Newton Abbott seemed painfully slow. Lost another 10 minutes between Exeter and Paddington.

That sounds more like being caught behind an Exeter stopper rather than an issue with the GUs

 

[TheBigD]

That sounds more like being caught behind an Exeter stopper rather than an issue with the GUs

Nope! Just a lacklustre performance from the IEP.
Nothing ahead on Traksy/realtraintimes, and we had a clear run.

 

[Horizon22]

Nope! Just a lacklustre performance from the IEP.
Nothing ahead on Traksy/realtraintimes, and we had a clear run.

Only one engine down would not result in that dramatic a performance decrease.

 

[TheBigD]

Only one engine down would not result in that dramatic a performance decrease.

Can only go by what the guard announced. She stated before we left Penzance that we were running with only 4 engines instead of 5. If they were additional faults or restrictions on the train she didn't announce them.

 

[Dai Corner]

Only one engine down would not result in that dramatic a performance decrease.

Speed restrictions?

Did the train in question take longer over the section than others the day?

 

[TheBigD]

Slightly off topic, but on a recent journey from Penzance to Paddington the guard announced that our train was on reduced power, only 4 engines instead of 5, and would lose time.
Whilst I know the IETs are not known for being sprightly over the devon banks I was surprised that it lost 25 minutes to Exeter, the section between Plymouth and Newton Abbott seemed painfully slow. Lost another 10 minutes between Exeter and Paddington.

Speed restrictions?

Did the train in question take longer over the section than others the day?

I may not have worded it well but it was 25 late by Exeter. It lost time all the way from Penzance. Lost 25 minutes in total between Penzance and Exeter, with a noticeably slow slog between Plymouth and Newton Abbott, then a further 10 on the Exeter to Paddington run.

 

[Horizon22]

Speed restrictions?

Did the train in question take longer over the section than others the day?

Without knowing the specific day it would be hard to tell. I just know that 4/5 GUs operational wouldn't lead to that serious decline - 3 possibly and 2 definitely.

 

[TheBigD]

Without knowing the specific day it would be hard to tell. I just know that 4/5 GUs operational wouldn't lead to that serious decline - 3 possibly and 2 definitely.

I know there used to be restrictions in place for HSTs on 1 power car over the devon banks, are there similar for IETs?
I'm guessing you wouldn't want to risk a set with, as you suggest 3 or just 2 GUs units?

 

[WatcherZero]

Phone GPS calculation wont be perfect, and neither will the trains speedo be 100% accurate, 99% accurate and it could really be doing 126 or 124 instead of 125.