Aberdeen - Inverness line: could further improvements be made?

[MadMac]

Getting away from airports for a moment: would there be any case for redoubling Inverurie-Insch and Kennethmont-Keith i.e. back to the late 1960s track situation?

 

[Tobbes]

Getting away from airports for a moment: would there be any case for redoubling Inverurie-Insch and Kennethmont-Keith i.e. back to the late 1960s track situation?

Was Aberdeen to Inverness ever double throughout?

 

[MadMac]

Was Aberdeen to Inverness ever double throughout?

Double from Aberdeen-Keith, I believe, but not beyond.

 

[Red Onion]

Getting away from airports for a moment: would there be any case for redoubling Inverurie-Insch and Kennethmont-Keith i.e. back to the late 1960s track situation?

I would even suggest a second platform at Keith to allow trains to pass in the platforms.

 

[Western Lord]

Double from Aberdeen-Keith, I believe, but not beyond.

Inverness to Dalcross was double track, from there to Keith always single.

 

[option]

Interesting article on what's been done as 'Phase 1'

Finishing the job - redoubling Aberdeen to Inverurie - Rail Engineer

Listen to this article Last year, the Aberdeen to Inverness Improvement Project (A2I) redoubled 8.5km of track between Aberdeen and Dyce as reported in issue 168 (October 2018). However, this redoubled track could not carry any passenger trains until this year’s completion of the 25.5km Aberdeen...

www.railengineer.co.uk

Journey time over the 173-kilometre-long Aberdeen and Inverness route is around 2 ¼ hours with an irregular, about two-hourly service frequency.
Whilst the Scottish Government’s long-term objective for the Aberdeen to Inverness line is the provision of an hourly service with a two-hour journey time,

It has taken four years to deliver A2I phase one – one of the UK’s longest redoubling projects – as well as a series of enhancements to provide more-efficient loop operation. On a single-track railway, this is perhaps likely to offer greater time savings than line speed enhancements.

Aberdeen to Inverurie is on the electrification plans. (from Montrose or Dundee)
I doubt that would see any increase in line speed, currently 75mph max from Aberdeen, but better acceleration should speed up journeys a little, & clear blocks quicker.
(Though Dundee-Aberdeen is 100mph max)

Inverness end is 75mph max as well, but from Inverurie to Elgin there's quite a few sections where it drops to 60mph. But there's only the IC services using that track, so not much 'bang for your buck' if you increase line speed there.


I suspect any further improvements would be bundled in with electrification, which is presumably a future phase, as mentioned here

Aberdeen to Inverness rail improvements | Transport Scotland

www.transport.gov.scot

 

[Wynd]

Double to Insch, redouble the tunnels at the north end of aberdeen, electrify to Inverurie, reintroduce inter-modal freight to Inverurie & Elgin.

Oh and reopen Platforms 8&9 at Aberdeen.

And provide for a Junction at Dyce for eventual reopening of Peterhead via Boddam.

 

[computerSaysNo]

Double to Insch, redouble the tunnels at the north end of aberdeen, electrify to Inverurie, reintroduce inter-modal freight to Inverurie & Elgin.

Oh and reopen Platforms 8&9 at Aberdeen.

And provide for a Junction at Dyce for eventual reopening of Peterhead via Boddam.

The tunnels at the north end of Aberdeen can't be redoubled as they're not wide enough for the enhanced loading gauge of the rest of the route. If they were wide enough they'd have been doubled as part of the current project.

 

[Wynd]

The tunnels at the north end of Aberdeen can't be redoubled as they're not wide enough for the enhanced loading gauge of the rest of the route. If they were wide enough they'd have been doubled as part of the current project.

How are we going to get inter-modal freight back on the line if they wont fit through the tunnels?

 

[computerSaysNo]

I doubt that would see any increase in line speed, currently 75mph max from Aberdeen, but better acceleration should speed up journeys a little, & clear blocks quicker.

If I'm remembering correctly the max linespeed between Inverness and Aberdeen is 85mph but a fair amount is around 75.
I can't see linespeed improvements being possible without realignment as the corners are the limiting factor. Better accelerating rolling stock would help slightly but the stations are fairly far apart so the majority of the time is spent at linespeed.

== Doublepost prevention - post automatically merged: 14 Feb 2022 ==

How are we going to get inter-modal freight back on the line if they wont fit through the tunnels?

Freight will fit through the tunnels at present as there is a single track through the centre of the tunnel (giving maximum height and space on both sides). If the north tunnel was double tracked then the tracks would need to be offset from the centre, closer to the edge wall and with less overhead clearance.

 

[Wynd]

If I'm remembering correctly the max linespeed between Inverness and Aberdeen is 85mph but a fair amount is around 75.
I can't see linespeed improvements being possible without realignment as the corners are the limiting factor. Better accelerating rolling stock would help slightly but the stations are fairly far apart so the majority of the time is spent at linespeed.

== Doublepost prevention - post automatically merged: 14 Feb 2022 ==


Freight will fit through the tunnels at present as there is a single track through the centre of the tunnel (giving maximum height and space on both sides). If the north tunnel was double tracked then the tracks would need to be offset from the centre, closer to the edge wall and with less overhead clearance.

My understanding is that the tunnels restrict the gauge of certain containers and also restrict the timetable.