Why does the 357 accelerate almost 2x as fast as every other electrostar?

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306024

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Not on the LTS line though

Having said that, do they reach these speeds on the GEML? For the short section they travel on it that is...
Hope not. Many years ago a few were used on the Southend Vic line just in the peak. But even then the main line was probably only 80 mph before it was increased to 90mph.
 

Bald Rick

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To answer the OP - they don’t.

I’ve been on AC electrostars that accelerate like the proverbial off a shovel. 377s and 387s on the MML, 379s in Anglia, Etc. No different to the 357.

Electrostars on DC do accelerate more slowly as they draw less power. But that’s limitation of the power supply, not the train.
 

SolomonSouth

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To answer the OP - they don’t.

I’ve been on AC electrostars that accelerate like the proverbial off a shovel. 377s and 387s on the MML, 379s in Anglia, Etc. No different to the 357.

Electrostars on DC do accelerate more slowly as they draw less power. But that’s limitation of the power supply, not the train.
No, the 377 in the video was on AC bruv... and the 357 is still quicker
 

Domh245

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Without ascertaining if all conditions were the same (no wheelslip, gradients the same, defensive driving techniques, etc) then you can't draw any meaningful comparisons about their acceleration
 

SolomonSouth

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Are 357s lighter?
Just looked it up - they are actually approx 15-20 tons lighter than 375s and 377s which are of the same length. No figures on weight for 379 and 387.
I guess the turbostar bodyshell may be lighter?

Without ascertaining if all conditions were the same (no wheelslip, gradients the same, defensive driving techniques, etc) then you can't draw any meaningful comparisons about their acceleration
Gradient doesn't make much, if any, difference off the line. It is only at higher speeds where you see it significantly affect train speeds. It was dry for all of them.
 

TRAX

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Gradient doesn't make much, if any, difference off the line. It is only at higher speeds where you see it significantly affect train speeds. It was dry for all of them.

What ? How ? Of course gradients make a difference to a train's takeoff and acceleration capabilities.
 

SolomonSouth

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What ? How ? Of course gradients make a difference to a train's takeoff and acceleration capabilities.
Well the momentum at lower speeds is less so tbh that would aid it less. Once it has momentum it affects it more. I think. It's like that with 376s I think. I could be wrong though
 

TRAX

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Well the momentum at lower speeds is less so tbh that would aid it less. Once it has momentum it affects it more. I think. It's like that with 376s I think. I could be wrong though

Have you ever ridden a bike ? Try starting one on a flat road and try the same on a hill, you’ll see the difference in acceleration.
 

D365

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What a strange discussion… is OP asking about the rated capability of the 357 vs other AC Electrostars, or whether the driving technique differs on c2c?
 

SolomonSouth

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What a strange discussion… is OP asking about the rated capability of the 357 vs other AC Electrostars, or whether the driving technique differs on c2c?
It is about the acceleration of the 357 vs AC 377 379 375 387 sorry if I confused you
 

Bald Rick

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It is about the acceleration of the 357 vs AC 377 379 375 387 sorry if I confused you

All else being equal (gradient, curvature, rail condition, wind direction); Acceleration is a function of the power / weight of the train, and the willingness of the driver to use the power to the full. What @D365 was asking is which of these two you were expecting an answer on (or both).
 

Deepgreen

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Just looked it up - they are actually approx 15-20 tons lighter than 375s and 377s which are of the same length. No figures on weight for 379 and 387.
I guess the turbostar bodyshell may be lighter?


Gradient doesn't make much, if any, difference off the line. It is only at higher speeds where you see it significantly affect train speeds. It was dry for all of them.
Dry? The 375, 376 and 378 videos are in wet conditions, and the 379 in damp conditions.
 

D365

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It is about the acceleration of the 357 vs AC 377 379 375 387 sorry if I confused you
As @Bald Rick has explained: do you want to know about how fast a unit is capable of accelerating, or how fast the drivers are trained to accelerate?
 

SolomonSouth

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As @Bald Rick has explained: do you want to know about how fast a unit is capable of accelerating, or how fast the drivers are trained to accelerate?
How fast a unit is capable of accelerating

There is audible Wheel Slip in at least 1 of the videos.
Oh yes sorry forgot to mention that
I will time the electrostars eventually, and see where they are all at to REALLY see which one is fastest
The 379 was done by railperf at 53 secs
The 377 was done by David Smith at about 50 secs
The 387 was done by railperf at 53 or so secs
Which leaves 357, 375, 376, and 378 which I will be timing using Vidometer.
All videos will be uploaded to my channel, here is a link: https://www.youtube.com/channel/UCdxvad0KyLgT-6GXZIti-2g
 

edwin_m

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Another pertinent factor is the proportion of the weight that is on motored axles. This determines the acceleration at low speeds, when full power can't be used as it would fry the motors or spin the wheels. I believe all the four-car Electrostars have three motor bogies, so should be pretty similar in this respect.
 

SolomonSouth

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Another pertinent factor is the proportion of the weight that is on motored axles. This determines the acceleration at low speeds, when full power can't be used as it would fry the motors or spin the wheels. I believe all the four-car Electrostars have three motor bogies, so should be pretty similar in this respect.
Should be, yet 357s seem vastly superior performers. Again I will time them when I get the chance in the dry and compare them to 379s 387s 377s 375s 376s to see
 

Bald Rick

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To get a fair comparison, you’ll need them on AC, on the same gradient, same length, unrestricted by speed limits or signals, and same weather conditions.
 

SolomonSouth

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To get a fair comparison, you’ll need them on AC, on the same gradient, same length, unrestricted by speed limits or signals, and same weather conditions.
Yeah. Easier said than done lmao

I was planning to do 0-75 but there's nowhere where a 376 can get get 0-75
 

SolomonSouth

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Exactly. But otherwise you’ll have smart rses like me saying it’s not comparable.
I know :) We need a top gear style drag race with their speedos edited all side-by-side to see who's REALLY quickest. Class 357 seems quickest 0-40 or so but it's probable a 377 is superior at the high speed ranges.

But what about 357 vs 345? Old vs new? Electrostar vs Aventra? Now THAT would be interesting, they both seem mental
 

TRAX

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There's also the fact that some trains will be healthier than others, even inside one class.
 
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