Stated maximum speed -safe maximum or absolute maximum?

[Harlesden]

The stated top speed of a Class 153 is 75mph.
If - hypothetically - a 153 was driven non stop from London to York, maintaining 75mph all the way, would the unit still be in a fit state for further service (aside from a need to be refuelled) or would it be in need of maintenance to restore it to a fit state?

 

[455driver]

Change ends and do it again, the train "should" be able to maintain its maximum speed for as long as necessary.

it wouldnt need refueling either.

 

[jon91]

Whether certain examples in the fleet would get to 75 mph is another question...

 

[bunnahabhain]

Yes, its actually better for the unit to spend a long trip running at its design speed than it is to run on stop/start diagrams. Look at the Hull Trains 170s, they posted casualty figures in excess of 70,000miles per failure I believe. Which was the highest of any diesel fleet and one of the highest in the country at the time.

 

[455driver]

Whether certain examples in the fleet would get to 75 mph is another question...

Are you trying to infer that some/most/all of them are gutless?

 

[Harlesden]

I never knew they had such a big tank.
I anticipate spending 84 minutes on one exactly two weeks from today

 

[jon91]

I might be...

At least they try, well you'd think they were with the absolute racket they make pulling away from stations.

 

[Cabview]

The stated top speed of a Class 153 is 75mph.
If - hypothetically - a 153 was driven non stop from London to York, maintaining 75mph all the way, would the unit still be in a fit state for further service (aside from a need to be refuelled) or would it be in need of maintenance to restore it to a fit state?

They have been known to go faster - like when a 153 gets coupled on to the back of a 170 (maximum speed 100mph) and the driver forgets it's there.

 

[LE Greys]

These are not the days when an A4 that hit more than 100 ran the risk of doing a middle big-end. The RSSB demands a 10% overspeed capacity for new stock. I'm not sure about older stock, but I can say I've been above 100 on Networkers a few times, and they always seemed to run fine. I've also heard rumours about the HST '140 Club' and 158s doing 'The Ton' in the days before OTMRs were fitted regularly. If found out, an 'under-reading speedometer' was often blamed. It's thus probably safe to assume that a 153 can do 83mph, downhill with a following wind, and still work normally afterwards. The unofficial record for a 14XX and Autocoach is 72mph, on a short run on the main line somewhere around Badminton, just for comparison.

 

[185]

I think for a 142 it applies to both scenarios :P

Long before Northern Rail, I have seen one doing 85mph on the ECML. Worrying really.

 

[notadriver]

The stated top speed of a Class 153 is 75mph.
If - hypothetically - a 153 was driven non stop from London to York, maintaining 75mph all the way, would the unit still be in a fit state for further service (aside from a need to be refuelled) or would it be in need of maintenance to restore it to a fit state?

The stated stop speed is the maximum cruising speed. However i've heard stories of the class 321s on the WCML having worn out traction motors due to extensive running at full speed for long periods of their life!

 

[plastictaffy]

Funny enough, notadriver, I happened to be talking to one of our drivers this morning about that very same thing. the Ol' Dusties have been known to make it to 110 on the "Rollercoaster" via Weedon!! Used to have to leave Wolverton early and wait time at MK - if they sat on the curve at Wolverton too long, the transformers would go bang. Of course this was before OTMR and suchlike!!

 

[northwichcat]

I think for a 142 it applies to both scenarios :P

Long before Northern Rail, I have seen one doing 85mph on the ECML. Worrying really.

I'm sure, one day on a 144 when the driver left his cab door open prior to departure, I saw some big notice indicating the unit is not to be driven at over 75mph.

 

[route:oxford]

When the 158s were subject to an emergency withdrawal in Scotland shortly after introduction, the 156s were required to meet the timetabling of the 158s.

They were definitely run at 90...

Perhaps a touch faster on a non-stop Perth-Stirling run.

 

[driver9000]

I never knew they had such a big tank.

On a full tank a 153 should be able to work around 1000 miles. Given the intervals between exams can be a couple of weeks there is no reason why it would need to be sent to a depot for maintenance work.

 

[northwichcat]

When the 158s were subject to an emergency withdrawal in Scotland shortly after introduction, the 156s were required to meet the timetabling of the 158s.

They were definitely run at 90...

Perhaps a touch faster on a non-stop Perth-Stirling run.

Isn't the true maximum speed of a train usually 20% higher than what it is built to 'cruise' at? (At least that's what people claimed when the subject of making 100mph class 350s run at 110mph.) If so 20% of 75 is 15 so the 156s would be able to run at 90mph.

 

[themiller]

As an old f**t, I seem to remember a 156 running on a publicity trip (soon after introduction) between Leeds and York being reported in the railway media to have reached something like 93MPH!

 

[306024]

On a full tank a 153 should be able to work around 1000 miles. Given the intervals between exams can be a couple of weeks there is no reason why it would need to be sent to a depot for maintenance work.

And a bit more. The Crown Point 153s are diagrammed up to 1500 miles between refuelling, and in practice can go a little further. Mind you it is surprising how soon you can clock up 1500 miles, even just on the Felixstowe branch, so they have to be returned to Crown Point quite frequently.

 

[Qwerty133]

I never knew they had such a big tank.
I anticipate spending 84 minutes on one exactly two weeks from today

Feel sorry for you and if its an EMT example I hope you don't get 153308 unless you want to see engineers at least twice

 

[driver9000]

And a bit more. The Crown Point 153s are diagrammed up to 1500 miles between refuelling, and in practice can go a little further. Mind you it is surprising how soon you can clock up 1500 miles, even just on the Felixstowe branch, so they have to be returned to Crown Point quite frequently.

I knew it was a 4 figure number, as long as the pretty red 'Engine Stopped' light doesn't appear when I'm working one I'm happy

 

[daikilo]

Isn't the true maximum speed of a train usually 20% higher than what it is built to 'cruise' at? (At least that's what people claimed when the subject of making 100mph class 350s run at 110mph.) If so 20% of 75 is 15 so the 156s would be able to run at 90mph.

This is dangerous talk. True maximum limit is what it is approved for. Someone knows whether it is due to the vehichle itself or to its dynamics on the track. That does not mean that there is no margin, just that if there is, it is there for a reason, and probably covers worst case scenarios.

I was lucky to be travelling in the early days of the HST and the occasional +10% was very comfortable, I have no knowledge of what we did to the track west of Swindon, nor what our stopping distance would have been with worn brakes on the day before an exam.

 

[notadriver]

This is dangerous talk. True maximum limit is what it is approved for. Someone knows whether it is due to the vehichle itself or to its dynamics on the track. That does not mean that there is no margin, just that if there is, it is there for a reason, and probably covers worst case scenarios.

I was lucky to be travelling in the early days of the HST and the occasional +10% was very comfortable, I have no knowledge of what we did to the track west of Swindon, nor what our stopping distance would have been with worn brakes on the day before an exam.

You just have to trust the driver. Even now except on lines fitted with cab signalling or TASS, its ultimately the drivers skill that gets you there safely.

 

[Ploughman]

The unofficial record for a 14XX and Autocoach is 72mph, on a short run on the main line somewhere around Badminton, just for comparison.

Just to make sure people realise that a 14xx is not a 142 / Pacer.

 

[Silv1983]

The stated top speed of a Class 153 is 75mph.
If - hypothetically - a 153 was driven non stop from London to York, maintaining 75mph all the way, would the unit still be in a fit state for further service (aside from a need to be refuelled) or would it be in need of maintenance to restore it to a fit state?

I occasionally drive the Northern "staff train" from Manchester to Preston (Via WCML) in the early hours. It quickly gets up to 75 but after a while the transmission "gears up" or whatever it does and a load of strain is taken off the engine etc. Sometimes cruising at 75mph is better than start/stop as mentioned above!

Should add it's a 153!

 

[northwichcat]

This is dangerous talk. True maximum limit is what it is approved for.

In what sense?

The maximum speed of a car could be 120mph but it is not permitted to travel at over 70mph on UK roads. Likewise if the maximum speed of a train could be 90mph but it's not allowed to travel at over 75mph on National Rail track.

 

[Cherry_Picker]

They have been known to go faster - like when a 153 gets coupled on to the back of a 170 (maximum speed 100mph) and the driver forgets it's there.

He will certainly know about it when he changes ends! Oil everywhere and a meeting with his traction inspector is in the post.

 

[notadriver]

In what sense?

The maximum speed of a car could be 120mph but it is not permitted to travel at over 70mph on UK roads. Likewise if the maximum speed of a train could be 90mph but it's not allowed to travel at over 75mph on National Rail track.

I think we have to be careful here. With the exception of sports/exotic cars, they are not tested for thousands of miles at the speeds the engine is capable of achieving. All trains are tested extensively at their rated maximum speed and beyond before being permitted in public service.

 

[notadriver]

I occasionally drive the Northern "staff train" from Manchester to Preston (Via WCML) in the early hours. It quickly gets up to 75 but after a while the transmission "gears up" or whatever it does and a load of strain is taken off the engine etc. Sometimes cruising at 75mph is better than start/stop as mentioned above!

Your train will start off in torque converter mode and change to direct drive at about 45 mph depending on what notch you're in

 

[455driver]

He will certainly know about it when he changes ends! Oil everywhere and a meeting with his traction inspector is in the post.

I did hear a rumour several years ago about an ECML driver ringing through to arrange fitters to meet the train at Kings Cross because the 91 on the back wouldnt go above 120mph and even struggled to get up to that speed.

Fitters meet him, they walk to the back of the train to see a rather warm 90 on the end of the train!

It might be messroom talk but it made me laugh anyway!

 

[driver9000]

I occasionally drive the Northern "staff train" from Manchester to Preston (Via WCML) in the early hours. It quickly gets up to 75 but after a while the transmission "gears up" or whatever it does and a load of strain is taken off the engine etc. Sometimes cruising at 75mph is better than start/stop as mentioned above!

Should add it's a 153!

The only "gear up" a 15x has is around 45mph when the transmission changes from Torque converter to fluid coupling. Once you manage to get them up to cruising speed it's relatively easy to keep them there using the mid range notches.