Random Ignorance

[Fred26]

Ask a stupid question...

1 - Can HST's, 90's and 91's be used with any coaching stock? East Coast use 91's with Mark IV coaches, but could they use them with the Mark III slam doors (and vice versa with HST's)? What about 90's? Can they be used with Mark IV's?
I ask because I wonder how easy it is to mix and match.

2 - Why does the Stansted Express have a catering/snack/drinks trolley? I travelled on these trains frequently in November last year from Tottenham Hale to Harlow and I didn't see them sell anything. It's not exactly a long ride from Liverpool Street to Stansted, so why bother?

 

[driver9000]

1 - HST trailers have Alliance buckeye couplers and are not compatible with drop head buckeye couplers such as those fitted to 90s and 91s. HST power cars are also unable to haul anything other than the HST mk3 trailers. The buffer fitted HST-DVT power cars were fitted with drop head buckeyes at the 'blunt' end for coupling to mk4 coaches but I'm not sure if they have been removed now. To enable a locomotive to haul HST trailers a barrier van is needed. Class 90s can be used with mk4 coaches (90024 was even painted into GNER livery for such a task).

 

[googolplex]

I seem to recall the Class 43s output a different power supply to the coaching stock than other locomotives, so the MK.3 coaches can only work with the HSTs without modifications.
I'm not sure about the others though.

 

[driver9000]

I seem to recall the Class 43s output a different power supply to the coaching stock than other locomotives, so the MK.3 coaches can only work with the HSTs without modifications.
I'm not sure about the others though.

HSTs use a three phase supply for the train electrics, HST trailers also don't have buffers. Grand Centrals former hauled mk3a coaches needed a lot of electrical work doing to them to make them compatible with HST stock.

 

[Fred26]

Very interesting. Thanks.

 

[O L Leigh]

1) Also Mk4's use Tightlock couplers within the rake rather than buckeyes, except for the TSO(E) where the loco is coupled which has conventional buffing gear and a drophead buckeye.

I'm not sure that the HST-DVT's were fitted with different couplers to pemit coupling to Mk4's because that would then have made them incompatible with Mk3 HST trailers. Fitting dropheads would also have required conventional buffing gear at the guards end, and this was never fitted. In fact, I don't believe they were ever modified at that end. However, the HST sets that were used with the Cl91's did require buffing gear at the outer end of the TGS so the loco could couple up.

2) The trolleys seem to do a good enough trade, so why not? Mind you, they're not really aimed at commuters making the short hop from Tottenham Hale to Harlow Town.

O L Leigh

 

[driver9000]

1)
I'm not sure that the HST-DVT's were fitted with different couplers to pemit coupling to Mk4's because that would then have made them incompatible with Mk3 HST trailers. Fitting dropheads would also have required conventional buffing gear at the guards end, and this was never fitted. In fact, I don't believe they were ever modified at that end. However, the HST sets that were used with the Cl91's did require buffing gear at the outer end of the TGS so the loco could couple up.

Sorry, I've got myself confused. You are right, the power cars were not modified and were coupled at the 'HST' end of the train, the TGS was modified to enable it to be coupled to a locomotive and was fitted with retractable buffers and dropehead buck eye coupler. The work was done on the 'van' end of the vehicle.

 

[ChrisCooper]

As far as I know the buckeye on HST powercars and coaches can couple to a standard drophead buckeye used on other passenger stock and some locos (33/1s, 73/2s, passenger 90s and 91s). Barrier vehicles used with HST trailers are just standard coaches, so the buckeye would be raised at the HST end and lowered (allowing the draw hook to be used) at the loco end. I presume when running with the HSTs the 91s would have coupled using their buckeye. The buffers and drophead buckeye were provided so that 86s and 87s could be used for testing of their TDM on the WCML, and also so other locos could couple in emergencies (particularly as originally the traction equipment on the HST powercar was isolated), same as why the powercars themselves got buffers.

91s can and have been used with other stock. The original plan with the 91s was that they would be used on sleeper trains (hence the blunt cab), and during testing and comissioning they were used to haul Mk1s. The 91 is a conventional locomotive. Anything can couple to a Mk4 TSOE, although as has been said internally Mk4 sets use tightlock couplers although I presume they can couple to a buckeye. Only the 91s, 89 and some 90s can use push pull with the Mk4s though as they use UIC connections for TDM rarther than RCH. All the locos have RCH jumpers too so can run push pull with Mk3 DVTs or Mk2 DBSOs (never happened with the latter, unlikely with the former).

A HST powercar could haul any other air braked, buckeye fitted coaching stock, the only issue being that they use a different train supply so could not provide ETS. The original New Measurement Train included Mk2s, but other than that HST powercars hauling anything but HST trailers has been very rare if it's ever happened (not counting barrier coaches). A HST powercar running as anything but a set is rare, although for transfers sometimes a single powercar will be sent out alone (with a barrier coach so a loco can couple up incase of emergency).

One thing I'm unsure on, didn't the HST powercars that were used as DVTs also have buffers and a drophead buckeye fitted at the inner end, as when first modified the traction was isolated (the engine being just used for train supply) and they needed to be able to be moved by other locos or shunters.

 

[Hydro]

The original New Measurement Train included Mk2s

One Mark 2, 999550, ran in the rake of the NMT whilst a Mark 3 trailer was fitted out with test equipment. No problems encountered as no test coaches draw any ETS supply. The NMT was rumoured to be top and tailed with 67's if NR didn't want to renew the lease on the 43's (they did, and re-engined them). This suggests that Mark 3 trailers can be hauled with a buckeye fitted loco.

 

[ChrisCooper]

I thought there were a pair of Mk2s, or am I thinking or the second set that was formed?

 

[Hydro]

The NMT, I'm 98% sure, only ever had one Mark 2 in the rake. It was the Track Recording Coach (999550) whilst the Mark 3 Production Vehicle was being prepared. The "other" set, I presume, would the set that 999550 subsequently went into (TRC rake) which is a loco hauled set comprising all Mk2's plus a Mk1 genny van. I stand to be corrected if necessary, this is all based on fairly current knowledge and I'm sure that there was potential for all sorts to be marshalled together when NMT was just starting out.

 

[hairyhandedfool]

AFAIK, anything with a buckeye can couple to anything with a tightlock provided they use two pieces of apparatus called 'a mushroom and toadstool'. These prevent the tightlock and buckeye from disengaging vertically, atleast thats what happens when a 319 rescues a mk1 based emu.

Electrically, HST trailers are only usuable in service with HST power cars, and other stock is only usuable in service with anything except HST power cars. That said, there was a barrier vehicle modified to work between a loco and HST trailers, I think it was fitted with it's own generator for train supply though.
--- old post above --- --- new post below ---
The NMT started out with 2 Mk2s in it's rake until more mk3s were ready.

(Info taken from pictures in Colin J Marsden's 'Power of the HST' pg 80-83)

 

[The Barlow Boy]

Sorry, I've got myself confused. You are right, the power cars were not modified and were coupled at the 'HST' end of the train, the TGS was modified to enable it to be coupled to a locomotive and was fitted with retractable buffers and dropehead buck eye coupler. The work was done on the 'van' end of the vehicle.

I remember those on the Leeds service. The HST car was to provide ETS but it was discovered that that did the engines a power of no good as they were virtually idling so control wiring was added so that they could provide traction power. With 6,300 horses at one end and another 2,250 horses at the other end the acceleration up Holloway bank could be lively to say the least!

.....

 

[Failed Unit]

Did the 91s ever haul Mk2s before the mk4s were complete. I remember a commuter train between Grantham and London that was mk2 formed but the 89 was at the front whenever I saw it.

I remember GNER had a plan which never came about to split up some mk4 sets to lengthen the mk4s to 10 coach. They were then going to forms some mk3 sets and pull with the 91s coming away from virgin. The mk4s would be 3 first + 6.5 standard on the Scotland route and peak Leeds. The mk3 2.5 first and 6 standard on the Leeds route. Never got off the drawing board. Don't know how many stations would have took a 10 car set anyway.

The plan would have split up 3 sets to make up 25x 10 car sets not sure where the 25th coach came from as 3x 8 is 24 and the buffets couldn't be used but they may have spares. These would then have got replaced by 4x 9 coach mk3 sets 3 to replace the ones broken up for the extension and the 4th to replace the damaged set from Heck and Hatfield.

In one respect in bet GNER regretted not doing it as if the had GC would not have had any coaches to start operations in the first place.

 

[O L Leigh]

Did the 91s ever haul Mk2s before the mk4s were complete. I remember a commuter train between Grantham and London that was mk2 formed but the 89 was at the front whenever I saw it.

Yup. It was a quick and easy way of commissioning the first batch of ten Cl91 locos ahead of the start of electric InterCity services.

O L Leigh

 

[Fred26]

2) The trolleys seem to do a good enough trade, so why not? Mind you, they're not really aimed at commuters making the short hop from Tottenham Hale to Harlow Town.

O L Leigh

If they do a good trade, that's okay. I just wonder how they manage to take anything at all.

 

[Royston Vasey]

One Mark 2, 999550, ran in the rake of the NMT whilst a Mark 3 trailer was fitted out with test equipment. No problems encountered as no test coaches draw any ETS supply. The NMT was rumoured to be top and tailed with 67's if NR didn't want to renew the lease on the 43's (they did, and re-engined them). This suggests that Mark 3 trailers can be hauled with a buckeye fitted loco.

I think this flexibility, and the lack of issue with a Mk 2 in the rake, is due to the NMT having a generator van:

A quick google image search brings this up:

 

[scotsman]

I remember GNER had a plan which never came about to split up some mk4 sets to lengthen the mk4s to 10 coach. They were then going to forms some mk3 sets and pull with the 91s coming away from virgin. The mk4s would be 3 first + 6.5 standard on the Scotland route and peak Leeds. The mk3 2.5 first and 6 standard on the Leeds route. Never got off the drawing board. Don't know how many stations would have took a 10 car set anyway.

Virgin used Class 90s and with the loco off the end, I imagine most stations to Leeds would be ok with 10 car

 

[Hydro]

I think this flexibility, and the lack of issue with a Mk 2 in the rake, is due to the NMT having a generator van:

A quick google image search brings this up:

Yes, all test trains have completely independent power supplies, nothing draws ETS.