Euro Loco HST 125 Speed Fix

DaveR · Post by **DaveR** » Wed May 08, 2002 5:46 am

Thanks for the info, interesting.

megatron · Post by **megatron** » Wed May 08, 2002 6:17 am

how big are the FGW hst consists?
they have about 8 coaches dont they? and out of Bristol Parkway there's a speed sign thats got 120 on it.
so surely the HST can get up to that speed (and obv a bit more)?
and unless i read it wrong didnt Colin mean the HST would STAY at 125mph on about 40% throttle? not GET to 125 on 40%?
please ignore me if im talking gibberish!!!

and also i think an order is going in for the package too with all the great comments made on here

regards
Guy

warriorgoku · Post by **warriorgoku** » Wed May 08, 2002 6:52 am

Ok I have run a world record consist (2x class43 locos + 3x mk3) and reached a speed (on flat terrain) of 125mph using the default .eng file. On the same area I reached 118mph using standard consist and default .eng file. However in some places on the ecml, I do reach speeds of up to 128mph with default .eng file and default consist.

warriorgoku · Post by **warriorgoku** » Wed May 08, 2002 7:07 am

Ok after further tests, I have found that the non-default(-1mph) .eng file is best. On the ecml I could reach a speed of 132mph with 100% power which sounds more accurate. I'm not sure how they do it with trains, but with planes you very rarely push the engines to 100% and only push it to about 95%.

I was unable to reach a speed of 100mph with 40% power using non-default .eng let alone 125mph. From now on, I am switching over to the non-default (-1mph) .eng.

Goingnorth · Post by **Goingnorth** » Wed May 08, 2002 7:10 am

They can easily do 125mph. But they are governed to 128.5 mph.

On GW lines they travel at 125 most of the time Between London/Bristol/S Wales. Elsewhere on GW they are limited by lower linespeeds.

To give you an idea on a level with a GW HST out of Paddington I rode in once; this is the sort of speeds you get:

Running on greens

Paddington :Start service to Swanasea
Royal Oak: 40mph
Ladbroke Grove: 80mph
Acton Main line (mp4): 100mph
Southall: 111mph
West Drayton: 125mph (about MP 12.5ish)

On the ECML, coming out of Peterborough, you're normally hitting 125 by the bottom of Stoke bank, just the Northside of Tallington.

Another run on a Xcountry HST out of Banbury we hit the Linespeed of 90mph just short of King's sutton. About 3 miles distance.

crepello · Post by **crepello** » Wed May 08, 2002 8:18 am

I think we are barking up the wrong tree by discussing whether it's +1mph or -1mph. For the friction thing to work properly (as per Joseph Realmuto's method) it needs to be +1mph. It's the other numbers in the friction section of the .eng file, and the coach .wag files, plus the MaxPower value that are important, and which together define the balancing speed of the train. It's those we should be looking at (and I can't cos my copy hasn't arrived yet!).

Simon,

Diesel locos are designed to operate most efficiently at 100% output. There is no holding back...

Stuart

elephant71 · Post by **elephant71** » Wed May 08, 2002 2:18 pm

Sorry if I didn't make it clear before - maintaining 125mph at 30-40% throttle once up to that speed is only achieved by changing both the -1mph friction value AND setting the maximum speed to 145mph as per James Hunt's version. With the -1mph in place it seems that the absolute maximum speed is about 1mph above whatever value is specified in the .eng file for it, which means I am keeping mine at 125mph. 145mph was done purely as an experiment.

I agree we shouldn't screw up the physics but I haven't noticed any other effect on the train's performance with the -1mph change other than allowing you the extra few mph at the top end.

Hope this helps.

Colin

<font size=-1>[ This Message was edited by: elephant71 on 2002-05-08 15:26 ]</font>

crepello · Post by **crepello** » Wed May 08, 2002 3:54 pm

*Bonk* *Bonk* *Bonk* [sound of hitting head against wall]

Any chance of letting me know what the values are (see above post), so I can try and figure out what's happening? I haven't received my copy yet.

Stuart

rabid · Post by **rabid** » Wed May 08, 2002 5:28 pm

I can personally verify that during a cab ride from Newcastle to York in the early eighties we were at 132mph on the Thirsk-Tollerton stretch. I seem to remember the driver saying there was some sort of governer, so it was obviously capable of more in the right circumstances.

crepello · Post by **crepello** » Wed May 08, 2002 6:48 pm

That does make sense, as half of that stretch is on a falling gradient.

Deltic9000 · Post by **Deltic9000** » Thu May 09, 2002 1:55 am

The Friction 1st line values are:
Engine
570N/m/s 0 1mph 12.04N/m/s 1.86

TF
461N/m/s 0 1mph 1.18N/m/s 1.86

TGS
460N/m/s 0 1mph 1.18N/m/s 1.86
TS
461N/m/s 0 1mph 1.18N/m/s 1.86

crepello · Post by **crepello** » Thu May 09, 2002 3:13 am

Thanks for that. What's MaxPower set at?

elephant71 · Post by **elephant71** » Thu May 09, 2002 2:17 pm

Mission for today - I must learn to read all replies properly before posting one myself!!!

Stuart - MaxPower is 1677kW, MaxForce and MaxContinuousForce are both 79.9kN, at least two of these seem spot on to me. If you want I can e-mail you the (unadulterated) .eng file - drop me a line at crbarks@lineone.net

Colin

crepello · Post by **crepello** » Thu May 09, 2002 4:32 pm

Colin,

I've dropped you a line.

Stuart

elephant71 · Post by **elephant71** » Thu May 09, 2002 5:32 pm

Stuart

Thanks, you now have mail too!

Colin