LNER train losing time persistently (16/03/2026)

[D1537]

Not sure where to put this, so please feel free to move it!

I noticed this train this morning, 1E02 0550 Edinburgh-King's Cross

Real Time Trains: 1E02

It dropped time continuously from the moment it left Edinburgh. I notice it spent 9 minutes at both Newcastle and York, which suggests that some sort of fixing of an issue might have been attempted.
It continued until being 41 late at Hatfield, at which point the slacker timings and recovery going into Kings Cross allowed it to claw back a few minutes. On its way it delayed both 1E03 and 1E04, which ended up being put behind the Lincoln service.

It was only at Kings Cross for 15 minutes before being sent back out with the same set (801109/111) 19 late on 1S13, where apart from some issue around New Southgate it appears to be able to keep time.

Real Time Trains: 1S13

So I was just interested - what sort of issue could have caused this, perhaps a limiting to 100mph for some reason? If so, what might that have been?

 

[GuyGibsonVC]

It had a bird in the pantograph and thus was limited to 100mph.

 

[D1537]

It had a bird in the pantograph and thus was limited to 100mph.

Thanks. So it was running (southbound) with the front pan (in this case, the front unit's pan) raised and that limits it to 100, correct?

 

[43367]

Thanks. So it was running (southbound) with the front pan (in this case, the front unit's pan) raised and that limits it to 100, correct?

A ten car runs with the front pan raised in the front set and the rear pan on the rear set, both pans in the middle are lowered.
If the rear set had its front pantograph raised, that is if the bird was lodged in the rear sets’ pantograph, then the set would be limited to 100mph.
I believe it’s because two pantographs raised in close proximity can cause a wave effect at high speed.

 

[D1537]

A ten car runs with the front pan raised in the front set and the rear pan on the rear set, both pans in the middle are lowered.
If the rear set had its front pantograph raised, that is if the bird was lodged in the rear sets’ pantograph, then the set would be limited to 100mph.
I believe it’s because two pantographs raised in close proximity can cause a wave effect at high speed.

Thanks, I didn't realise this. Presumably then they managed to extract said bird at Kings Cross.

 

[Peter Mugridge]

Thanks, I didn't realise this. Presumably then they managed to extract said bird at Kings Cross.

I don't think they did; the return working consistently lost additional time after a late start.

 

[andy33gmail]

I don't think they did; the return working consistently lost additional time after a late start.

Presumably they would need to take the train to a section of track where the overhead lines could be isolated?

 

[Segedunum]

I don't think they did; the return working consistently lost additional time after a late start.

That was just down to loss of path AIUI.

 

[Hbbz9392]

A ten car runs with the front pan raised in the front set and the rear pan on the rear set, both pans in the middle are lowered.
If the rear set had its front pantograph raised, that is if the bird was lodged in the rear sets’ pantograph, then the set would be limited to 100mph.
I believe it’s because two pantographs raised in close proximity can cause a wave effect at high speed.

apologies if it's off-topic but why is the wave effect undesirable? i tried to google it but it didn't give me a good answer

 

[D1537]

I don't think they did; the return working consistently lost additional time after a late start.

Well I was wondering that, but it kept time from Peterborough to York and Newcastle to Edinburgh, including doing Peterborough to Newark in 25 mins which is 105mph start to stop.

It's about to come back south on 1E23 so I presume it's fixed.

 

[IanM]

apologies if it's off-topic but why is the wave effect undesirable? i tried to google it but it didn't give me a good answer

In very simple terms, the pantograph pushes up on the wire, which in turn displaces the wire upwards briefly as the pantograph passes underneath.

That can start a wave effect as the train moves along, in exactly the same way that the bow on a violin displaces the strings to produce a sound.

With a single pantograph, the natural damping of the wire means everything is stable again once the next train comes along. With two pantographs in quick succession, like a 10 car Azuma, the wire doesn’t recover fully before the next pan comes along.

The closer the pans, the worse the effect (hence 10 cars run with front and rear pans in use to maximise the time between them passing a given point on the wire).

If the pans are too close, then the wire will still be bouncing as the next pan comes along and the rear pan will not make good contact. You’d see arcing and sparking and the rear unit would be loosing power, and in an extreme case you’d set up a wave in the wire which might get out of control and cause damage.

 

[D1537]

1E23 is running to time.

 

[WillC]

You mean like..
(Image shows destruction of Tacoma Narrows bridge, due to resonance effect of wind blowing across it.)

 

[merry]

You mean like..

Well, a bit like it, Tacoma Narrows was a wind induced resonance.

In this case the wire is damped but maybe not enough for the middle pan to avoid bounce, which leads to arcing or worst case the pan being tangled, maybe pulled off. All undesirable, so running slower is preferred over cancellations, until the issue can be properly fixed.

 

[ejstubbs]

Tacoma Narrows was a wind induced resonance.

That is the often repeated explanation, but the consensus in physics and engineering circles is somewhat different these days, particularly taking into account that the oscillation was not at one of the structure's resonant frequencies. "Wind-driven amplification of self-induced torsional oscillation" is the explanation generally accepted.

It might seem like a bit of a fine distinction, but it means that the factors that need to be taken into consideration when designing new structures have to be different to what the straightforward resonance model would suggest..

Tacoma Narrows Bridge (1940) - Wikipedia

en.wikipedia.org

It is very improbable that the resonance with alternating vortices plays an important role in the oscillations of suspension bridges. First, it was found that there is no sharp correlation between wind velocity and oscillation frequency such as is required in case of resonance with vortices whose frequency depends on the wind velocity.[39]

(None of which is to say that resonant phenomena don't exist, or that they don't need to be taken into account when running pantographs in continuous proximity - i.e. on the same train - at high speed along a 25kV OHLE contact wire.)

 

[JohnofWessex]

I remember my oldest then aged about 10 driving a trolleypole fitted tram rather enthusiastically and the overhead started tripping the light fantastic

 

[MarlowDonkey]

With a single pantograph, the natural damping of the wire means everything is stable again once the next train comes along. With two pantographs in quick succession, like a 10 car Azuma, the wire doesn’t recover fully before the next pan comes along.

I believe this was the stated reason why the APT was designed with both power cars adjacent in the centre of the train, despite the operational inconvenience of having to duplicate things like buffet facilities.

 

[hexagon789]

I believe this was the stated reason why the APT was designed with both power cars adjacent in the centre of the train, despite the operational inconvenience of having to duplicate things like buffet facilities.

I thought it was BR reluctance at running a 25kV supply cable through the passenger accommodation, even over the roof.

The APT-P power cars (NDM) ran off one pantograph, the other NDM being supplied via roof cable from the adjacent NDM.

 

[MarlowDonkey]

I thought it was BR reluctance at running a 25kV supply cable through the passenger accommodation, even over the roof.

The APT-P power cars (NDM) ran off one pantograph, the other NDM being supplied via roof cable from the adjacent NDM.

If they put the power cars at the ends of the train, they would either have needed to run a 25kV cable fron one end of the train to the other or have two pantographs. They ruled that out at the time because of the catenary oscillation problem but that now seems to have been overcome with the 80x trains.

 

[hexagon789]

If they put the power cars at the ends of the train, they would either have needed to run a 25kV cable fron one end of the train to the other or have two pantographs. They ruled that out at the time because of the catenary oscillation problem but that now seems to have been overcome with the 80x trains.

There are speed restrictions though, on the 80x classes if running in pairs.

Outermost pans are full speed.

Both front or both rear, then it's 100mph.

Inner pair, then it's 80mph.