Class 43?

[Class 153]

If the class 43 had no mk3s could it go even faster than 125 mhp?

 

[asylumxl]

No. It'd need the MK3s to have enough air pressure and will probably be restricted to about half that.

 

[Darandio]

IIRC, isn't a set only permitted to travel at full line speed with a minimum of 5 Mk3's? I seem to recall reading this in the Grand Central thread, in the early days when there were reliability issues with some of the coaches. Services had to be caped because they couldn't short form a set as it wouldn't keep to timed paths with the restricted speed.

Just had a quick look and am sticking with 5 coaches as a minimum. Any record runs, i.e the diesel record on the ECML and even the recent FGW Plymouth run were with five Mk3's.

 

[HugePilchard]

I'm sure Hydro has mentioned this on a thread about the NMT, mentioning that due to the number of braked axles present on the train, it gets restricted to a certain speed.

 

[Old Hill Bank]

Class 43's were 90 mph diesel hydraulics, 125 would never have worked.
As for the HST Power Cars, 150 mph plus no problem you just have to take out the device that cuts power at 132 mph and disconnect the OTMR
LOL

 

[rail-britain]

Class 43's were 90 mph diesel hydraulics, 125 would never have worked.
As for the HST Power Cars

HST power cars were reclassified as locos, Class 43, away back in the 1990s

The speed limit when moving power cars from Craigentinny to Edinburgh Waverley was 60mph
When a loco was hauling a dead power car the speed limit was 45mph

 

[OMGitsDAVE]

IIRC, isn't a set only permitted to travel at full line speed with a minimum of 5 Mk3's? I seem to recall reading this in the Grand Central thread, in the early days when there were reliability issues with some of the coaches. Services had to be caped because they couldn't short form a set as it wouldn't keep to timed paths with the restricted speed.

Just had a quick look and am sticking with 5 coaches as a minimum. Any record runs, i.e the diesel record on the ECML and even the recent FGW Plymouth run were with five Mk3's.

There are some GC sets running around with 4, and they manage to keep time?

 

[Nym]

It's more to do with the available brake force than the number of carrages, modifications can be made to increase brake force. But you need to go back to thinking of a complete rake having a certain amount of brake force, and it needed such an amount of brake force to stop in time, if it doesn't it's restricted to lower speeds. eg. unbraked freight trains.

 

[rail-britain]

There are some GC sets running around with 4, and they manage to keep time?

Limited to 110mph they should be able to keep to time, given the lighter train load and timetable padding / allowances
Might arrive a little late at York, but won't be much (probably incurring an additional 5 to 10 minutes)

 

[Kingfisher200262]

HST power cars were reclassified as locos, Class 43, away back in the 1990s

The speed limit when moving power cars from Craigentinny to Edinburgh Waverley was 60mph
When a loco was hauling a dead power car the speed limit was 45mph

This old chestnut again! Can we agree to differ on whether an HST is a DEMU or a loco hauled train set?!??!

The HST power car (aka Class 43 loco) is one of the few locos that is capable of braking its own weight and in theory at least, there is no reason why it shouldn't be allowed to run light at its maximum permitted line speed of 125 mph.

Grand Central HST sets regularly operate as 2 + 4 formations at 125 mph. The issues in the early days were around the inexperience of the company, the uncertainty of the LHCS to HST conversion on the trailers and the obvious issues of unreliability, all of which have been dispelled over time.

 

[starrymarkb]

Diesel electric unit?

 

[GNERman]

Grand Central HST sets regularly operate as 2 + 4 formations at 125 mph. The issues in the early days were around the inexperience of the company, the uncertainty of the LHCS to HST conversion on the trailers and the obvious issues of unreliability, all of which have been dispelled over time.

GC HST's don't regularly run 2+4's, 2+5's and 2+6's are the norms, with 2+7's making irregular appearances. However, at the moment, due to coaches at Kilmarnock for repaint and work, 2 HST's are running as 2+4.

 

[Kingfisher200262]

GC HST's don't regularly run 2+4's, 2+5's and 2+6's are the norms, with 2+7's making irregular appearances. However, at the moment, due to coaches at Kilmarnock for repaint and work, 2 HST's are running as 2+4.

Sorry, you're quite right, of course. Perhaps I should have used the work occasionally. The point I was making was that it doesn't require any special dispensation to do so.

 

[Rhydgaled]

I'm sure Hydro has mentioned this on a thread about the NMT, mentioning that due to the number of braked axles present on the train, it gets restricted to a certain speed.

My memory may be incorrect, but I seem to remember pictures of the New Measurment Train with mark 2 intermediate vehicles. If there are mark 2 vehicles in the train that might explain the limited top speed (assuming it is limited to less than 125mph).

 

[Yew]

Of course, If you meant the macimum theoretical top speed of two 43's running with no carriages between them. The record for a HST full set is 156mph. I bet you could get close to 200 if you had favorable track conditions

 

[ainsworth74]

The record for a HST full set is 156mph.

Erm it's a 148mph not 156. It was set going down Stoke Bank in 1987 with an HST set that was testing a new bogie design.