Why aren't there more tilting trains in the UK?

[Joshrowlands]

Hi guys I was just wondering because the class 390 Pendolinos and class 221 Super Voyagers are the only tilting trains in the UK, why aren't there more?

Don't tilting trains allow for higher speeds around bends and therefore improve services? For instance say there was two train companies operating the same route on the same line but one company had high speed tilting trains wouldn't people chose the company with faster journey times to get there quicker and therefore the company would earn more money?

It seems like the UK are so behind on rail technology can anybody name any reasons why we don't have more tilting trains? I understand they are probably more expensive but wouldn't it make their return on the company for the fact of more people choosing to travel with them for reduced journey times? If not can someone name more reasons? I'm interested to know

 

[HSTfan!!!]

At a guess gauging is probably the main issue.

 

[Murph]

As a whole, there is basically zero competition between companies for the major journeys, at least as far as passenger choice goes. The competition is at franchise bidding and award level, when something close to a monopoly is awarded for each of the main lines and commuter areas for the next 5-15 years.

So, the thing with customers choosing the faster journey just doesn't happen other than express vs. stopper. There's usually only 1 choice of express, and 1 choice of stopper.

Edit: Oh yeah, and we're not really lagging behind as such. The tilting technology that we do have was invented by British Rail for the APT project, then sold to Fiat for the Pendolino.

 

[HSTEd]

Overall journey times have not actually improved significantly since privatisation - the idea now is to pack in as many trains as possible at the minimum cost - often resulting in trains being slowed to make them easier to timetable.
Upgrades (like those to support tilting trains) cost money, and noone is willing to pay for them - especially after the WCRM and now the GWML projects have turned into overbudget disasters.
The idea now is capacity is king and will be provided by packing ever more seats into smaller spaces. At least until HS2 arrives.

 

[TheJRB]

Something else to consider is how much more tilting would advantage lines where it could be implemented. Large areas of the East Coast Main Line and Great Western Main Line which are already 125 mph capable would not benefit as that's the top speed deemed safe with traditional signalling. I think if tilting is adopted elsewhere, it probably won't be until ERTMS is more prevalent.

 

[Murph]

Something else to consider is how much more tilting would advantage lines where it could be implemented. Large areas of the East Coast Main Line and Great Western Main Line which are already 125 mph capable would not benefit as that's the top speed deemed safe with traditional signalling. I think if tilting is adopted elsewhere, it probably won't be until ERTMS is more prevalent.

Yup, that's very true. It was mainly the very curvy WCML that stood to benefit significantly from tilting. There's even sections of the ECML which are basically already good for no-tilt 140mph (and tested past 160mph), but restricted to 125mph due to safety concerns for signalling. You need a significant percentage of the line's distance to have speed restrictions which are primarily due to curves before there's enough advantage from tilt to outweigh the disadvantages.

 

[cjmillsnun]

Hi guys I was just wondering because the class 390 pendolinos and class 221 super voyagers are the only tilting trains in the UK why aren't there more?

Don't tilting trains allow for higher speeds around bends and therefore improve services? For instance say there was two train company's operating the same route on the same line but one company had high speed tilting trains wouldn't people chose the company with faster journey times to get there quicker and therefor the company would earn more money?

It seems like the UK are so behind on rail technology can anybody name any reasons why we don't have more tilting trains? I understand they are probably more expensive but wouldn't it make their return on the company for the fact of more people chosing to travel with them for reduced journey times? If not can someone name more reasons? I'm interested to know

Tilting trains had a bit of a stigma until the Class 390 Pendolinos came along.

Britain actually developed the first tilting trains and was the first to introduce them into passenger service. (see atp-p.com)

The problem was, it was not as developed as it could've been, as well as being introduced in a cold winter, causing the tread brakes to freeze. Added to that, BR laid on a lot of booze for the press prior to the inaugural run, the high speed and the tilting (it tilted perhaps a bit too well), caused the rather worse for wear journos to feel a bit queasy. So when they wrote it up as sick inducing, then they had frozen on brakes on the next few runs. BR decided to put them out of service whilst this was all sorted, and they re-entered service as an unadvertised relief train a few months later.

By this time, BR had lost their bottle on the project and quietly killed it. They then sold the technology to FIAT who were working on similar technology. The FIAT trains are called Pendolino....

The other factor is that there are few routes that would benefit.

The main one is the West Coast Main Line, which is where the 390s are.

The speed increase with tilting trains is 90% passenger comfort. Most trains can run a fair bit faster than they do, however the passengers would quite rightly complain about the centrifugal forces they are subjected to. Tilting mitigates this.

In reality, our railway isn't that bad, most people look at the TGV in France and say our railways are crap, however if you look at the rest of SNCF, most of it is creaking and old.

We have one of the most modern fleets in the EU, and a lot of money is being spent on the infrastructure for them.

 

[WatcherZero]

Its also very expensive to do, you need to install balises along the route telling the train how far it is allowed to tilt (though that could be done with GPS and a onboard computer nowadays), you have to ensure the tracks are far enough apart that two tilting trains don't hit each other, you need to move all the things alongside the track that a tilting train might hit such as sign posts, overhead gantries, lineside equipment etc..

Its all a lot of work for not much improvement as few lines are fast enough for the train to gain any advantage from tilting.

 

[najaB]

Its also very expensive to do, you need to install balises along the route telling the train how far it is allowed to tilt

This will need to be done for ERTMS anyway so it's not a massive extra expense.

...you have to ensure the tracks are far enough apart that two tilting trains don't hit each other

They would be tilting in the same direction so it's less of a problem than it initially appears. It's more likely that a tilting and non-tilting train would come into contact.

...you need to move all the things alongside the track that a tilting train might hit such as sign posts, overhead gantries, lineside equipment etc..

Alternatively the balises can inhibit tilt where it would take the train out of guage.

Its all a lot of work for not much improvement as few lines are fast enough for the train to gain any advantage from tilting.

There are a few other places on the network where it could be advantageous - typically anywhere that's got lots of curves.

 

[LNW-GW Joint]

I was on a Czech Pendolino last year, and it never exceeded 160kph (100mph), which is the national speed limit.
The gain (30mins on Prague-Ostrava, a 3-hour trip) was in tilting round 120km curves at 160kph.
It's similar in Switzerland where it's not sheer high speed but the differential from the original (relatively low) line speed which matters.
Our lines like that would be the Highland or Transpennine routes, or across Devon/Cornwall.
In Europe they don't have to bother with balises, as it is "tilt at will" within a larger gauge.
We do like to make things complicated!

 

[LateThanNever]

Tilting trains had a bit of a stigma until the Class 390 Pendolinos came along.

Britain actually developed the first tilting trains and was the first to introduce them into passenger service. (see atp-p.com)

The problem was, it was not as developed as it could've been, as well as being introduced in a cold winter, causing the tread brakes to freeze. Added to that, BR laid on a lot of booze for the press prior to the inaugural run, the high speed and the tilting (it tilted perhaps a bit too well), caused the rather worse for wear journos to feel a bit queasy. So when they wrote it up as sick inducing, then they had frozen on brakes on the next few runs. BR decided to put them out of service whilst this was all sorted, and they re-entered service as an unadvertised relief train a few months later.

By this time, BR had lost their bottle on the project and quietly killed it. They then sold the technology to FIAT who were working on similar technology. The FIAT trains are called Pendolino....

The other factor is that there are few routes that would benefit.

The main one is the West Coast Main Line, which is where the 390s are.

The speed increase with tilting trains is 90% passenger comfort. Most trains can run a fair bit faster than they do, however the passengers would quite rightly complain about the centrifugal forces they are subjected to. Tilting mitigates this.

In reality, our railway isn't that bad, most people look at the TGV in France and say our railways are crap, however if you look at the rest of SNCF, most of it is creaking and old.

We have one of the most modern fleets in the EU, and a lot of money is being spent on the infrastructure for them.

Thoroughly agree! Next stop the Devon Switchbacks - otherwise known as the Devon Banks which cause probs even now! Surely this would give Plymouth its faster journeys without a too major investment?

 

[Ze Random One]

Remember, also, that tilting increases infrastructure maintenance costs -- not just because of the extra infrastructure that (may be/is) necessary to support tilt, but because the tilt only modifies the forces experienced by those within the train, it does not change the forces present at the wheel/rail interface, meaning that you increase the forces on the track (particularly to the outer rail), since the route may only be canted for 100mph, but the train is at 120mph.

The upshot of this is that tilting trains cannot be seen in isolation, and the cost of ongoing infrastructure maintenance may, in some cases, outweigh the benefits of speed increases.

(Disclaimer: I'm not a physicist or an engineer. I'm sure others will be able to explain far better than I)

 

[Peter Mugridge]

The speed increase with tilting trains is 90% passenger comfort. Most trains can run a fair bit faster than they do, however the passengers would quite rightly complain about the centrifugal forces they are subjected to. Tilting mitigates this.

Try doing Paris Montparnasse - Bordeaux non stop on a TGV before the extension to the LGV opens next year; once off the existing LGV near Tours they run at up to 135mph on conventional track, quite twisty in places* - and it's much more comfortable than doing the WCML with tilt.


*Reminiscent of what the Trent Valley and Weedon used to be like before they were straightened out a bit.

 

[BantamMenace]

Was it ever looked at for the transpennine route?

Would enable a replacement electric fleet for the class 185s to be tilting for the WCML duties and transpennine duties.

Might be worth looking at between Stockport and Sheffield too.

 

[phil beard]

Tilting on the British Loading Gauge also reduces considerable the internal dimensions of the trains. I always prefer the width of a Mark III compared with a Pendolino. They are very cramped.

 

[edwin_m]

Tilting on the British Loading Gauge also reduces considerable the internal dimensions of the trains. I always prefer the width of a Mark III compared with a Pendolino. They are very cramped.

This is partly the result of the structure of the Pendolino apparently requiring small windows and very thick sides, and partly also the poor interior design which manages to make it look more claustrophobic than it is. The Voyager/Meridian types have a similar profile for tilting (although only some of class 221 actually tilt) but the Meridian layout in particular gives a much greater impression of space.

 

[nuneatonmark]

I thought that one of the problems with the APT was that it was designed that the tilt fully countered the effect of the bend i.e. it tilted too much. This meant that some people felt queasy because their body was telling them two contrary things i.e. you're going around a corner but you're still fully upright. I thought the solution to this on the Pendos was that the tilt did not fully correct the cant on the bend hence no one getting queasy? I may be completely wrong about this!

 

[Murph]

I thought that one of the problems with the APT was that it was designed that the tilt fully countered the effect of the bend i.e. it tilted too much. This meant that some people felt queasy because their body was telling them two contrary things i.e. you're going around a corner but you're still fully upright. I thought the solution to this on the Pendos was that the tilt did not fully correct the cant on the bend hence no one getting queasy? I may be completely wrong about this!

As I understand it, the first problem was that it wasn't tilting quickly enough, so was initially untitled with cornering force which got cancelled a moment or 2 later. They solved that fairly quickly. The second problem was as you described, where the visual cornering didn't match the forces felt inside the ear, solved by backing off the tilt a little to leave some feeling.

The biggest problem, however, was the free bar for the press the night before a flagship press demo run, leading to a bunch of unprofessional news hacks being ill on the run.

 

[AnonymousUser1]

This is partly the result of the structure of the Pendolino apparently requiring small windows and very thick sides, and partly also the poor interior design which manages to make it look more claustrophobic than it is. The Voyager/Meridian types have a similar profile for tilting (although only some of class 221 actually tilt) but the Meridian layout in particular gives a much greater impression of space.

ditto the mk4 carriage , al beit only designed to allow max 6deg tilt according to various sources

 

[edwin_m]

ditto the mk4 carriage , al beit only designed to allow max 6deg tilt according to various sources

Indeed so. I think the Voyagers and Pendolinos also tilt only to 6 degrees, as a consequence of not needing to compensate fully for lateral acceleration as posted above. However I'm not certain of this.

 

[BananaRepublic]

Britain actually developed the first tilting trains.......

Totally incorrect. The first experiments with tilting trains go back to the 1930's.
SNCF were experimenting with tilt in the 1950's and the Germans and Spanish in the the 1960's. The 1970's also saw the Japanese and Italians involved with tilt and a number of tilting trains went into mostly limited and in some cases short lived service.
All these experimental and production trains used passive tilt systems.

The British were the first to develop and try active tilt, which they incorporated in the ATP, having looked at the tilt work that was being developed elsewhere.

.....and was the first to introduce them into passenger service. (see atp-p.com)......

The first tilting train to go into service was the Canadian National Railways Turbo in 1968. Others passive tilt trains saw service during the 1970's.

 

[cjmillsnun]

You're quite right. I should've made it clear that I was referring to active tilt

 

[yorkie]

Don't tilting trains allow for higher speeds around bends and therefore improve services?

Yes, but don't you need a business case?

For instance say there was two train companies operating the same route on the same line but one company had high speed tilting trains wouldn't people chose the company with faster journey times to get there quicker and therefore the company would earn more money?

Some people won't. I chose to do London-Stoke on LM because it was a quarter of the price.

It seems like the UK are so behind on rail technology can anybody name any reasons why we don't have more tilting trains? I understand they are probably more expensive but wouldn't it make their return on the company for the fact of more people choosing to travel with them for reduced journey times? If not can someone name more reasons? I'm interested to know

You answered your own question: it is very expensive.

There are not many routes where you would get a viable business case, and if one company is running faster trains and another company slower stopping trains, the latter isn't going to benefit as much, and bigger differential between train speeds means pathing becomes even more difficult.

 

[BananaRepublic]

......They then sold the technology to FIAT who were working on similar technology. The FIAT trains are called Pendolino.......

The first FIAT Pendolino was developed in the late 1960's, based on a passive (pendulum) system. Later Pendolino designs went into passenger service in the mid-1970's, long before ATP hit the tracks.

What FIAT bought from BR was the patents for the hydraulic active tilt bogies, but they simplified and re-engineered the actual tilt mechanisms to be more effective and smoother in operation. They also reduced the maximum tilt angle.
The FIAT interpretation was also easier and more cost effective to manufacture and maintain.

 

[DownSouth]

I thought that one of the problems with the APT was that it was designed that the tilt fully countered the effect of the bend i.e. it tilted too much. This meant that some people felt queasy because their body was telling them two contrary things i.e. you're going around a corner but you're still fully upright. I thought the solution to this on the Pendos was that the tilt did not fully correct the cant on the bend hence no one getting queasy? I may be completely wrong about this!

Yes you are correct. The solution to this is to work out tilt angles for a given speed using the standard cant deficiency formulae applied for the track plus the tilt angle, so that the passengers experience a similar degree of lateral force as they would on a slower non-tilting train.

The passive tilting train designs from Talgo don't have this problem - they use a system which naturally cannot provide full compensation.

Tilting on the British Loading Gauge also reduces considerable the internal dimensions of the trains. I always prefer the width of a Mark III compared with a Pendolino. They are very cramped.

A situation which in any other country would have been solved by increasing the clearance on the inside of a tilt-enabled curve, not by imposing an additional restriction on the train design.

The biggest problem, however, was the free bar for the press the night before a flagship press demo run, leading to a bunch of unprofessional news hacks being ill on the run.

This is a load of rubbish, and a perfect example of why the 'attack the messenger' strategy rarely works in the world of public relations.

Other passengers experienced the same issues as the drunk journalists, and the system was eventually altered in recognition of the fact.

You're quite right. I should've made it clear that I was referring to active tilt

The APT was not the first active tilt train either.

The MLW-Bombardier LRC entered service before the APT-P, and unlike the APT-P it was a mature enough product to stay in service once introduced. Some of the more recent versions of the LRC include the Acela Express in the USA, the ICE-T and ICE-TD in Germany and the Voyager series units in the UK.
--- old post above --- --- new post below ---

The first FIAT Pendolino was developed in the late 1960's, based on a passive (pendulum) system. Later Pendolino designs went into passenger service in the mid-1970's, long before ATP hit the tracks.

What FIAT bought from BR was the patents for the hydraulic active tilt bogies, but they simplified and re-engineered the actual tilt mechanisms to be more effective and smoother in operation. They also reduced the maximum tilt angle.
The FIAT interpretation was also easier and more cost effective to manufacture and maintain.

People overestimate the importance of the BR technology to the Fiat Ferroviaria system for the second-generation Pendolino. They only bought the patents to access one component of the hydraulic system, and only to use it as a shortcut to where they were headed with their own development anyway.

They could just as well have gone for the Bombardier LRC active tilt system - except if that happened Bombardier probably would have protected their IP a bit more closely than BR, which would in turn have led to Fiat Ferroviaria getting a license-build arrangement rather than a design purchase.

 

[sprinterguy]

Indeed so. I think the Voyagers and Pendolinos also tilt only to 6 degrees, as a consequence of not needing to compensate fully for lateral acceleration as posted above. However I'm not certain of this.

Pendolinos tilt to 8 degrees - just shy of the 9 degrees required to fully compensate for lateral acceleration.

 

[Murph]

This is a load of rubbish, and a perfect example of why the 'attack the messenger' strategy rarely works in the world of public relations.

Other passengers experienced the same issues as the drunk journalists, and the system was eventually altered in recognition of the fact.

Well, unless there's any dispute about a good number of them being drunk on the job, surely it's fair comment to say that they (the drunk or hungover ones) were acting unprofessionally and in no position to judge the queasiness factor of the train?

One thing that really can't really be disputed is that the media unfairly tore APT to shreds, and that it was unjustified media negative-hype that killed it, not the quality of the project and prototype itself. BR are certainly not blameless, but the media hold most of the blame from my point of view, as the prototypes were later proven to be a perfectly good train and indicated that it would have been reasonable to go ahead with the APT-S. The media set the WCML back about 15 years, and cost the taxpayer a small fortune in lost R&D, in their typical frenzy for a headline which didn't bother to let facts get in the way of a good invented scandal.

BR's failings:

1) They pushed it out the door before it really was ready.
2) They shouldn't have had the media on it so soon, or suffering from the effects of alcohol.

 

[starrymarkb]

Yes you are correct. The solution to this is to work out tilt angles for a given speed using the standard cant deficiency formulae applied for the track plus the tilt angle, so that the passengers experience a similar degree of lateral force as they would on a slower non-tilting train.

The passive tilting train designs from Talgo don't have this problem - they use a system which naturally cannot provide full compensation.


A situation which in any other country would have been solved by increasing the clearance on the inside of a tilt-enabled curve, not by imposing an additional restriction on the train design.

This is a load of rubbish, and a perfect example of why the 'attack the messenger' strategy rarely works in the world of public relations.

Other passengers experienced the same issues as the drunk journalists, and the system was eventually altered in recognition of the fact.

The APT was not the first active tilt train either.

The MLW-Bombardier LRC entered service before the APT-P, and unlike the APT-P it was a mature enough product to stay in service once introduced. Some of the more recent versions of the LRC include the Acela Express in the USA, the ICE-T and ICE-TD in Germany and the Voyager series units in the UK.
--- old post above --- --- new post below ---

People overestimate the importance of the BR technology to the Fiat Ferroviaria system for the second-generation Pendolino. They only bought the patents to access one component of the hydraulic system, and only to use it as a shortcut to where they were headed with their own development anyway.

They could just as well have gone for the Bombardier LRC active tilt system - except if that happened Bombardier probably would have protected their IP a bit more closely than BR, which would in turn have led to Fiat Ferroviaria getting a license-build arrangement rather than a design purchase.

The ICE-T uses Fiat's tilt system under licence, The ICE-TD uses a home grown Siemens system (and as a first attempt it was rather problematic!)

 

[Wyvern]

There is another point. THe development of track mounted signalling devices had not matured in the 'seventies and the APT was deriving its tilt signal from on-board accelerometers. A system that was not as robust.

Although the APT-E had travelled many miles, it was rarely given the chance for its ful capabilities to be tested due to working within sheduled service patterns. The record-breaking run wasa on a straight section of the GWML, a more significant run was a few weeks later on the MML.

Finally the APT-P was bulit by the CM&EE (not the research) and various simplifying design alterations were made. Whether this contributed to the failure is a matter of debate.

Finally, the project as a whole was not a faiilure - British Rail would have recouped much or all of its investment in patent licencing fees.

 

[contrex]

Britain actually developed the first tilting trains and was the first to introduce them into passenger service. (see atp-p.com)

In 1938, the Atchison, Topeka and Santa Fe Railway tried out a passive-tilt coach which they ran on the San Diegan train; it made people seasick and was not a success.

The first tilting train to enter into regular service in North America was the United Aircraft TurboTrain, used by Canadian National Railways in 1968. It should be rightfully considered the first tilting train in service in the world. It assured daily service between Montreal and Toronto at speeds of 160 km/h, until it was replaced by Bombardier LRC trains in 1982. United Aircraft Turbos were also used by Amtrak between Boston and New York. The UAC Turbos had a passive tilt mechanism based on a four-bar arrangement, and they inspired the second generation of TALGO trains.

All these, including the TALGO Pendular pre-dated the APT in passenger service.