Timetable Padding

[westv]

I'm sure I read that the Azuma will shave 6 or so minutes of the daily London to Hull service.
However, I have an email ticket confirmation from May 2008 showing the service left Kings X at 17:20 and arrived at 20:00. I also have an email ticket confirmation from June 2018 showing the service left Kings X at 17:18 and arrived at 20:05.
So there has been an additional 7 minutes of padding built into the timetable. Cutting the journey time by 6 minutes will not even put it back to where it was 10 years ago.
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[geoffk]

I'm sure that if we compare the current GWML timetable with that in 1976, when the HSTs were new, the contrast will be even more extreme. Not just padding in that case but a lot of extra stops. Does the Hull service make the same stops?

 

[westv]

I'm sure that if we compare the current GWML timetable with that in 1976, when the HSTs were new, the contrast will be even more extreme. Not just padding in that case but a lot of extra stops. Does the Hull service make the same stops?

Yes, same stops and yes, of course I'm sure there are other examples across the network.

 

[The Planner]

Difficult to prove if it is padding or not without comparing the two schedules. The current one has 2 minutes public time vs working time at Hull, which would have been put in by the TOC, but there doesn't appear to be anything else. It has 5½ minutes pathing allowances spread across the schedule but they are there to keep it apart from other trains.

I thought the GWML one had been done to death with speed changes towards Paddington and modern driver standards putting paid to the old times.

 

[greatkingrat]

In 2008 it didn't stop at Grantham, which will explain some of the difference.

 

[Ianno87]

As I recall....

1720 moved to 1719 when FCC added the Royston peak extras in around 2010 or so... moving it forward by 1 minute gave a path for an additional 1723 Kings Cross-Royston - 4 minutes being required due to Networkers slightly out-accelerating HSTs for the first few miles out of King's Cross.

1719 then became 1718 in May with the Thameslink recast - the sequence of trains at 3 minute planning headway is...

1700 Edinburgh
1703 Leeds
1706 Peterborough fast
[Gap for eventual Brighton-Cambridge from Finsbury Park]
1712 Ely fast
[Gap for King's Cross-Cambridge stopper over Welwyn Viaduct]
1718 Hull Exec
[Gap for Horsham-Peterborough north of Finsbury Park]
1724 Baldock-Semi-fast
[Lost path due to 1724 calling at Welwyn North]
1730 Newcastle...
Etc

So in each case the extra minute on the Hull Exec is a by product of getting an extra 2tph in the timetable each time - but still being constrained by the same slot through Doncaster et al.

That's why I detest the lazy term "padding". It's actually careful tightening up of the timetable structure to get the most capacity out of the infrastructure.

 

[westv]

In 2008 it didn't stop at Grantham, which will explain some of the difference.

I could have sworn the stops are the same but I must be wrong.

 

[westv]

A

That's why I detest the lazy term "padding". It's actually careful tightening up of the timetable structure to get the most capacity out of the infrastructure.

As far as passengers are concerned, when their service becomes slower, it's padding.

 

[Bikeman78]

As I recall....

1720 moved to 1719 when FCC added the Royston peak extras in around 2010 or so... moving it forward by 1 minute gave a path for an additional 1723 Kings Cross-Royston - 4 minutes being required due to Networkers slightly out-accelerating HSTs for the first few miles out of King's Cross.

1719 then became 1718 in May with the Thameslink recast - the sequence of trains at 3 minute planning headway is...

1700 Edinburgh
1703 Leeds
1706 Peterborough fast
[Gap for eventual Brighton-Cambridge from Finsbury Park]
1712 Ely fast
[Gap for King's Cross-Cambridge stopper over Welwyn Viaduct]
1718 Hull Exec
[Gap for Horsham-Peterborough north of Finsbury Park]
1724 Baldock-Semi-fast
[Lost path due to 1724 calling at Welwyn North]
1730 Newcastle...
Etc

So in each case the extra minute on the Hull Exec is a by product of getting an extra 2tph in the timetable each time - but still being constrained by the same slot through Doncaster et al.

That's why I detest the lazy term "padding". It's actually careful tightening up of the timetable structure to get the most capacity out of the infrastructure.

Curiously 1H10 has two minutes pathing time between Hitchin and Arlesey even though there is nothing in front of it.

 

[Ianno87]

Curiously 1H10 has two minutes pathing time between Hitchin and Arlesey even though there is nothing in front of it.

The 1706 King's Cross-Peterborough is booked Fast Line all the way to St. Neots, including a Fast Line stop at Biggleswade. Presumably stops it having to get across at Hitchin and getting tangled up in stuff that might be going on there. The pathing time in 1H10 keeps it behind the 1706 (http://www.opentraintimes.com/schedule/W60781/2018-08-14)

In any case, (2) is required south of Huntingdon anyway, as it catches up the 1525 Horsham-Peterborough across the fen (http://www.opentraintimes.com/schedule/W64322/2018-08-14)

As far as passengers are concerned, when their service becomes slower, it's padding.

As far as passengers are concerned, if they get extra trains, it's not.

 

[Wilts Wanderer]

As far as passengers are concerned, when their service becomes slower, it's padding.

I don’t recall ever hearing passengers mentioning the word ‘padding’, unless referring to a lack of it on their seat!

 

[jon0844]

I don’t recall ever hearing passengers mentioning the word ‘padding’, unless referring to a lack of it on their seat!

Some do, because they've likely heard the term being used by rail staff or other passengers. They probably don't appreciate that when you run more and more services and run at full capacity, trains invariably get slowed down. Plus with greater passenger numbers, dwell times at some stations are increased because it's obvious that no train will come and go in 20 seconds.

It's the same as passengers often think trains skip stops to save money. Sure, there are operational benefits and it may save a later cancelled service, but a train with stops skipped does not avoid a penalty.

 

[FenMan]

I don’t recall ever hearing passengers mentioning the word ‘padding’, unless referring to a lack of it on their seat!

It was a common topic among passengers when SWT introduced their concept of a right time railway. Some of the padding was generous to say the least.

 

[The Planner]

I would be willing to bet that was public time vs working time at the destination though.

 

[Wilts Wanderer]

I think initially the recast SWT services were known for extended booked stops at random places like Fleet and Surbiton. Perhaps an overabundance of engineering allowances?