@notadriver will know (if he’s still on here).
Without derailing the thread, I agree. I happen to enjoy Calais and have many times used the Calais Daytripper ticket and the walked from the port into the town. However, Calais doesn't have the appeal of other destinations that the average consumer enjoys so unfortunately will never happen.I always thought it could be cool to have frequent services to Calais. Make a daytrip so much easier.
I think actual 300 kph running only happens between the north downs tunnel and the start of the Lenham loops. I reckon 5 minutes worth at most.They are 186mph / 300kph only East of Ebbsfleet (that's where the line speed increases above 140mph, plus the time taken to accelerate - through the gradient down to the Medway viaduct helps with this)
This urban myth again...
Trains are timed with 5% recovery, as per standard practice on high speed lines. So the running time is calculated based 140mph running, then inflated by 5% (thus corresponding to ~125mph).
But trains routinely will run at 140mph, either to catch up minor late running, or will just arrive stations slightly early.
Believe it or not, Line speed is 230kph for that stretch, and yes, Class 395's get a 225kph indication throughout except the approaches to stations and the approaches to/from the end of HS1 at St Pancras and Ashford. On the press and stakeholders runs we touched 230kph but in normal service drivers are careful to observe the units 225kph maximum service speed. The quite steep and frequent changes in gradient make it difficult to maintain a steady speed. Hence drivers are happy to let speed hover around the 135 to 138mph mark to avoid over speeding downhill.I thought it was 225kph to stay consistent with the 140mph conversion. Is the line speed 230 while TVM only displays 225? Not that the 5kph would make much of a difference but can trains get away with running at a few kph over 225 in service?
Im speculating but why wouldn’t the TVM display 230kph (or 300kph south of Ebbsfleet for that matter.) Its a display of the maximum speed permitted by the signalling system and route, not the train itself. The driver will regulate his maximum speed against the speedometer, not the TVM display.
I wonder if drivers ever get confused and have ever assumed the speedo is still in kph on the 3rd rail sections? Although to be fair the Javelins are quite slow on 3rd rail and struggle to do more than 90mph.no the TVM display will only display the up to the maximum speed for the type of train - not the actual line speed.
Afaik the speedos say 'mph' or 'km/h' after the actual figure displayed depending on mode presumably to avoid confusion but you'd hope drivers wouldn't get confused to start with!I wonder if drivers ever get confused and have ever assumed the speedo is still in kph on the 3rd rail sections? Although to be fair the Javelins are quite slow on 3rd rail and struggle to do more than 90mph.
Stratford Intl to Ebbsfleet Intl is timed at 10 mins start to stop. You can’t do that at 125 mph max. Also Ashford to Ebbsfleet 18 minutes - standard timing. Impossible at only 125 mph.
No. It is almost impossible to achieve a 125mph average speed on the fastest section alone from Stratford to Ashford - even excluding the Ebbsfleet stop -Ah thanks. Makes me wonder whether "125mph" is somehow reflecting an overall average maximum speed from St Pancras to Ashford, i.e. the higher speed needed east of Stratford is balanced off by the lower attainable speed St Pancras-Stratford.
No. It is almost impossible to achieve a 125mph average speed on the fastest section alone from Stratford to Ashford - even excluding the Ebbsfleet stop -
Fastest average speed achieved so far is 119mph on a service train.
It doesn't really matter. As explained by @notadriver the maximum achievable speed between St Pancras and Stratford is around 105mph. From Stratford to Ebbsfleet and between Ebbsfleet and Ashford trains will reach a maximum 140 mph..but the demanding gradients mean speed varies quite significantly with lows of around 125mph at the highest summits.No, I meant as in take the average of:
1. Maximum speed needed to meet the timetable St Pancras-Stratford
2. Maximum speed needed to meet the timetable Stratford-Ebbsfleet
3. Maximum speed needed to meet the timetable Ebbsfleet-Ashford
Trying to source a rational explanation for "125mph", other than a simplistic off the cuff number punted by a journalist in 2009 (which is probably more likely)
Thanks for clearing that up! Does this mean that ES drivers get 230kp/h on their TVM as far as Ebbsfleet?Believe it or not, Line speed is 230kph for that stretch, and yes, Class 395's get a 225kph indication throughout except the approaches to stations and the approaches to/from the end of HS1 at St Pancras and Ashford. On the press and stakeholders runs we touched 230kph but in normal service drivers are careful to observe the units 225kph maximum service speed. The quite steep and frequent changes in gradient make it difficult to maintain a steady speed. Hence drivers are happy to let speed hover around the 135 to 138mph mark to avoid over speeding downhill.
On the climb out of the Medway Valley the gradient can reduce train speed by as much as 20 kph even on full power.!
Yes, except when stopping in the platforms - where lower limits apply. Plus the start and approach to and from St Pancras has lower limits for a while.Thanks for clearing that up! Does this mean that ES drivers get 230kp/h on their TVM as far as Ebbsfleet?
Thanks for clearing that up! Does this mean that ES drivers get 230kp/h on their TVM as far as Ebbsfleet?
Using the term 'trundle' here very lightlyEurostar schedules are quite generous and it is not unknown to trundle through Kent at no more than 140mph and still arrive at the Eurotunnel portal on time.
Yup. Last time I travelled on one, I noticed it was fractionally faster in the UK than France. Not quite sure if there's a reason for that.I have recorded 300 kmh (and a tad over) on eurostars in the UK.
Fractionally?Yup. Last time I travelled on one, I noticed it was fractionally faster in the UK than France. Not quite sure if there's a reason for that.
By 1 or 2mph (i.e. 187mph in UK, 185mph in France).Fractionally?
French TGV-SE PAris - Lyon schedule was designed for full power application for just 1/3 of the 264 mile journey and using the kinetic energy of the train to coast over the gradients like a roller coasterI remember reading a while back that if a 373 was set on the cruise control at 186mph the actual speed would vary as low as 155mph depending on the gradients, if a skilled driver was powering it manually and maintaining close to linespeed a full 10 minutes can be saved between Calais and Paris, or made up if running late. It would be interesting to know more about SNCF driving techniques - various online cab view videos show the current speed and some drivers definitely seem to coast over gradients and avoid using the brakes, at the cost of losing speed uphill. Presumably if the schedules are designed to allow it, it saves on component wear and power.
Speeds can fluctuate wildly so a few kph over or under isn't an issue. The TVM signalling will cut in if 10 kph over the posted limit, So 310kph on 300kph track. 240kph on 230kph track etc.By 1 or 2mph (i.e. 187mph in UK, 185mph in France).
Yes, the sound insulation is so good, and HS track so smooth that 140mph can feel like less than 70mph on a normal train! Certainly a class 153 at 60mph is noisier and bouncier!Using the term 'trundle' here very lightly
From 186mph, speed can drop to 168mph from Medway bridge up to North Downs tunnel - but not sure full power is used uphill!I remember reading a while back that if a 373 was set on the cruise control at 186mph the actual speed would vary as low as 155mph depending on the gradients,
I remember reading a while back that if a 373 was set on the cruise control at 186mph the actual speed would vary as low as 155mph depending on the gradients, if a skilled driver was powering it manually and maintaining close to linespeed a full 10 minutes can be saved between Calais and Paris, or made up if running late. It would be interesting to know more about SNCF driving techniques - various online cab view videos show the current speed and some drivers definitely seem to coast over gradients and avoid using the brakes, at the cost of losing speed uphill. Presumably if the schedules are designed to allow it, it saves on component wear and power.
The London to Paris path intersects with Eurotunnel and then the main Paris to Brussels TGV line. There are several mins allowance on the St Pancras to Eurotunnel UK portal to ensure Eurostar hits its Eurotunnel slot in case of any slight delay. The same applies between Calais and Lille Fretin Junction to ensure that the Paris - Lille path can be achieved.Amongst other things, it is quite a demanding mental workload on the driver to keep powering off and on to "hug" the line speed profile for long sustained runs - I can see why cruise control is attractive in managing this.
I understood it was a 15km/h tolerance at over 160km/h?Speeds can fluctuate wildly so a few kph over or under isn't an issue. The TVM signalling will cut in if 10 kph over the posted limit, So 310kph on 300kph track. 240kph on 230kph track etc.
Coasting where practical is very much routine, plus the French go very much for 'defensive' driving I understand. Any whiff of a cautionary signal aspect and on come the brakes. I seem to recall reading this caused issues when the Eurostars first started running - UK drivers were used to running at speed on double yellows whereas the French drivers would kill the speed off too much and lose time until they got into the habit of driving less cautiously under UK signalling where braking distances for signals are a lot more variable.I remember reading a while back that if a 373 was set on the cruise control at 186mph the actual speed would vary as low as 155mph depending on the gradients, if a skilled driver was powering it manually and maintaining close to linespeed a full 10 minutes can be saved between Calais and Paris, or made up if running late. It would be interesting to know more about SNCF driving techniques - various online cab view videos show the current speed and some drivers definitely seem to coast over gradients and avoid using the brakes, at the cost of losing speed uphill. Presumably if the schedules are designed to allow it, it saves on component wear and power.
I understood it was a 15km/h tolerance at over 160km/h?
Coasting where practical is very much routine, plus the French go very much for 'defensive' driving I understand. Any whiff of a cautionary signal aspect and on come the brakes. I seem to recall reading this caused issues when the Eurostars first started running - UK drivers were used to running at speed on double yellows whereas the French drivers would kill the speed off too much and lose time until they got into the habit of driving less cautiously under UK signalling where braking distances for signals are a lot more variable.
I suppose it would be thinking about it, because you would always need to brake under cautionary aspects because of the standard braking distances. I've always thought of French signalling as more a sort of hybrid of route and speed signalling as route indications are given at junctions in addition to the permissible speed unlike most other pure speed signalling systems where you just get the relevant speed indicationThat’s understandable, given that French railway signalling is based on speed principles (as opposed to route-based UK signalling.) Running at linespeed on anything other than the least restrictive aspect is anathema so I imagine that braking reflex is deeply ingrained in a professional driver.
That might have been the case when classic UK infrastructure was in use, but it's now TVM pretty much throughout, with standardised signal spacing.I understood it was a 15km/h tolerance at over 160km/h?
Coasting where practical is very much routine, plus the French go very much for 'defensive' driving I understand. Any whiff of a cautionary signal aspect and on come the brakes. I seem to recall reading this caused issues when the Eurostars first started running - UK drivers were used to running at speed on double yellows whereas the French drivers would kill the speed off too much and lose time until they got into the habit of driving less cautiously under UK signalling where braking distances for signals are a lot more variable.
That might have been the case when classic UK infrastructure was in use, but it's now TVM pretty much throughout, with standardised signal spacing.
I'd have thought ES would simply drive to whatever speed TVM tells them is authorised.
There won't be many double yellows between Paris (Gonesse) and London (St Pancras approaches).