Splitting 158s at Shrewsbury - only one going on

[JoeGJ1984]

Today I was on the 1924 from Birmingham New Street to Shrewsbury, which was formed of two 158s. The train went on to Chester, but only the front two carriages went beyond Shrewsbury (they I presume split the units at Shrewsbury). What is the purpose of splitting the units (the second one does not go on anywhere else)?

Also I've seen it the other way round - at Shrewsbury waiting to get a train to Birmingham New Street originating at Holyhead - a 158 waiting with the corridor connection open and a second 158 coming from Holyhead and then the units coupled up and all went to Birmingham New Street. What's the purpose of this splitting/joining units?

 

[Welshman]

Presumably ATW is making the most of the units it has, and doubling-up on the Birmingham International-Shrewsbury section, where I presume the flow is bigger, and then just running a single unit through to Holyhead and back.

 

[NSE]

It happens fairly frequently. Its just the main flow of passengers are between Birmingham and Shrewsbury. They do it often on Cambridge/Kings Lynn trains. 8 carriages from London to Cambridge then split, with only four up to Kings Lynn with four waiting for four from Kings Lynn before returning to London.

 

[158_Sprinter]

When splitting at Shrewsbury, one portion carries on to Holyhead, the other goes on to Aberystwyth

 

[Welshman]

I think a study of Table 75 of the NR Timetable will show that is not the case. The Birmingham-Shrewsbury-Holyheads run on the opposite hour to the Birmingham-Shrewsbury-Aberystwyths, and as far as I am aware the Aberystwyths are already double sets as they detach/join the Pwllheli portion at Machynlleth.

Of course, the stock diagrams will change if they ever manage the hourly Shrewsbury-Abertystwyth service they's been hoping for long enough to achieve!

 

[Liam]

Sometimes happens at Dundee, 158+170 from Edinburgh, 170 goes onto Aberdeen, the 158 works a later service back to Edinburgh

 

[Crossover]

When splitting at Shrewsbury, one portion carries on to Holyhead, the other goes on to Aberystwyth

Not true I don't think

I think a study of Table 75 of the NR Timetable will show that is not the case. The Birmingham-Shrewsbury-Holyheads run on the opposite hour to the Birmingham-Shrewsbury-Aberystwyths, and as far as I am aware the Aberystwyths are already double sets as they detach/join the Pwllheli portion at Machynlleth.

Of course, the stock diagrams will change if they ever manage the hourly Shrewsbury-Abertystwyth service they's been hoping for long enough to achieve!

RE: Aberystwyth train, that is what usually happens. There are occasions (later in the day I think usually) where the train runs as a 4 car to Aberystwyth and doesn't split en-route (unless one goes off empty at Mach but I'm sure I have heard of a 4 car going to Aberystwyth before)

 

[BrummyBoy]

I'm sure the 19:30 service from Aberystwyth is a four car 158.

 

[Tracky]

Most trains are booked to run as 4 cars between Shrewsbury and Birmingham.

Aberystwyth/Pwllheli trains leave Birmingham as 4 and divide at Mach.

Holyhead trains leave Birmingham as 4 and divide at Shrewsbury.

The 2 left behind at Shrewsbury become the front of the incoming Holyhead-Birmingham.

When turning around at Birmingham International trains from Holyhead form trains to Aberystwyth and trains from the Cambrian form trains to Holyhead.

 

[158_Sprinter]

Not true I don't think



RE: Aberystwyth train, that is what usually happens. There are occasions (later in the day I think usually) where the train runs as a 4 car to Aberystwyth and doesn't split en-route (unless one goes off empty at Mach but I'm sure I have heard of a 4 car going to Aberystwyth before)

My mistake, sorry. I had forgotten that the spare units made up the Holyhead - Birmingham return journey, and I've been on the incoming unit into Shrewsbury waiting for what seemed like ages to pull into the platform, while the outgoing Holyhead train passed, doh!

 

[Waverley125]

last time I did Aberystwyth-Shrewsbury (an 1130 sunday service) it was a single 158 to Shrewsbury where we joined another 158 to go through to Crewe.

 

[Gareth Marston]

Most trains are booked to run as 4 cars between Shrewsbury and Birmingham.

Aberystwyth/Pwllheli trains leave Birmingham as 4 and divide at Mach.

Holyhead trains leave Birmingham as 4 and divide at Shrewsbury.

The 2 left behind at Shrewsbury become the front of the incoming Holyhead-Birmingham.

When turning around at Birmingham International trains from Holyhead form trains to Aberystwyth and trains from the Cambrian form trains to Holyhead.

The pattern above is more or less spot on for 0900 through to 1900 the diagrams change somewhat early in day and later. The 0727 & 0927 to Aber are 2 car weekdays the 0927 4 on Saturday all the others are 4 car. The last 2 UP trains from Aber are 2 car.

The 0727 to Aber uses Platform 6, 0927,1127,1327,1527,1727 & 1927 use 4 the last service 2150 Platform 3. All arrivals are scheduled for 5. The Holyhead/INTL's all use 4 though some early/late Holyhead bound 2 car trains may use 3