Heatwave July 2022

[whole diary]

[Marlburian]

I've been wondering what I would have done today, had I still been based in London (Tilehurst-Paddington-Lambeth North). No problem for me heat wise getting in to the office for 0800. Would I have stayed late waiting for the daytime heat to dissipate? Guess I would have checked the availability of late rush-hour trains. But then the deteriorating COVID situation would have diminished my conscientiousness. Perhaps I would have arranged a visit away from the office on Tuesday or Wednesday (both days might not have been acceptable). Or a couple of days' leave?

I commuted in 1972-73 and can recall the old carriages - eight to a compartment, get on the train at Paddington and tug hard at the two handles on those little windows that were usually closed, musty smell of the upholstery - not to mention that of other passengers after a hot day in London.

[stuving]

Straight track laid to the full current NR^» (Network Rail - home page) standard is stress-free at 27^o, and no action is called for until the rail temperature rises by 37 K. So some mitigation may be needed above 59^o, and speed restrictions only above 64^o.

That's rail temperature, of course, and a number of things can push that well above local air temperature, which itself can be well above a weather-station value. And there are a lot of features (e.g. curves, points, bridges, and uncorrected defects) that can reduce those limits and result in local restrictions.

Series One OLE^▸ (Overhead Line Equipment, more often "OHLE") is designed for an air temperature range of -18-40^o. The main factor in this is the adjustment range of the Tensorexes, which is 1 m. The maximum wire run is 750 m (each side of a centre clamp) which combined with the expansion coefficient of the wires gives a temperature range of 74 K. And the maximum wire temperature is, correspondingly, set at 56 ^o.

The extra heating comes from the sun and from traction current, so running a reduced service or at reduced speed should provide a little extra leeway. However, that effect may be too hard to predict to be useful. There is a separate calculation of maximum current, using the same limit of 56^o and an air temperature of 28^o. Here the wind speed is critical, as any cooling effect from it allows a large current increase: at 0.45 m/s (1 mph) to 532 A, and at 3 m/s to over 964 A.

Given that there are hundreds of wire runs, and these will be tested today with higher temperatures than they have ever seen, I'd guess that any problems on GWR^▸ (Great Western Railway) will arise at those few runs that were set up out of spec, or have been altered without the full setup being repeated. There must be a few out there.

[jamestheredengine]

Looks like something's up with the Severn Tunnel now. The 1348 Paddington to Swansea, which got to Bristol Parkway 128 late, has now been sitting there for 20 minutes. The dreaded "LB" is appearing on Traksy. There's something described as a loco coming the other way now:
https://www.realtimetrains.co.uk/service/gb-nr:59044/2022-07-18/detailed

[ChrisB]

From BBC^» (British Broadcasting Corporation - home page) News

Be grateful this isn't happening here - it's in Spain.....

Spain heatwave: Moment of shock as train is surrounded by wildfires

Passengers travelling on a Spanish train were alarmed as their train momentarily stopped and wildfires could be seen on both sides of the track.

The footage was captured in the Spanish province of Zamora.

A spokesperson from rail operator Adif told the Associated Press that the passengers were never in danger.

Video in link above.

[stuving]

On the other hand ... a large fire (1000 Ha) south of Avignon has been confidently attributed to sparks from the brakes of a goods train. And, having been brought under control on Friday morning, it has now started up again. The local mayor (of Graveson) has been muttering to himself (and any passing reporter) about suing SNCF^▸ (Societe Nationale des Chemins de fer Francais - French National Railways).

That line has of course been closed, but it's "only" the old main line to Marseille - not the LGV^▸ (Large Goods Vehicle), and for local trains there are other ways round.

[broadgage]

Some of the large fires near the railway in France and perhaps elsewhere could have been fought from a train.  A train of water tankers can carry a vast amount of water, perhaps a thousand tons as compared to a few tons carried by a fire engine.

Start with say ten tank wagons, and between each pair of tanks place a suitable open topped wagon with sides about 1.2 meters high. Each wagon to contain a couple of portable engine driven fire pumps and two firemen. Connect the pump suction to the tank outlet, and the pump discharge to a short length of standard fire service delivery hose.

Firefighting from the top of the water tankers is obviously not applicable to routes with OHLE, but from a suitable wagon should be ok.

[Richard Fairhurst]

Of all the days... I had a meeting in London today. Both GWR^▸ (Great Western Railway) and TfL^» (Transport for London - about) acquitted themselves splendidly.

Cotswold Line services were starting/terminating at Oxford, which led to the unusual sight (both ways) of a 5-car IET^▸ (Intercity Express Train) in Platform 2, the bay platform. It fits very snugly!

Elizabeth Line aircon greatly appreciated... I can't imagine trying the Central Line on a day like this.

The morning trains were fairly busy, but the evening was as quiet as the grave - I think I was one of only two people in coach A on the 17.20 out of Paddington.

All services in the evening were limited to 60mph. Trundling along on the fasts at 60mph between Paddington and Reading is a weird feeling.

[IndustryInsider]

Some of the large fires near the railway in France and perhaps elsewhere could have been fought from a train.  A train of water tankers can carry a vast amount of water, perhaps a thousand tons as compared to a few tons carried by a fire engine.

Start with say ten tank wagons, and between each pair of tanks place a suitable open topped wagon with sides about 1.2 meters high. Each wagon to contain a couple of portable engine driven fire pumps and two firemen. Connect the pump suction to the tank outlet, and the pump discharge to a short length of standard fire service delivery hose.

Firefighting from the top of the water tankers is obviously not applicable to routes with OHLE, but from a suitable wagon should be ok.

Wouldn’t only a small percentage of these fires be within reach of hoses on the train?

[broadgage]

Some of the large fires near the railway in France and perhaps elsewhere could have been fought from a train.  A train of water tankers can carry a vast amount of water, perhaps a thousand tons as compared to a few tons carried by a fire engine.

Start with say ten tank wagons, and between each pair of tanks place a suitable open topped wagon with sides about 1.2 meters high. Each wagon to contain a couple of portable engine driven fire pumps and two firemen. Connect the pump suction to the tank outlet, and the pump discharge to a short length of standard fire service delivery hose.

Firefighting from the top of the water tankers is obviously not applicable to routes with OHLE, but from a suitable wagon should be OK.

Wouldn’t only a small percentage of these fires be within reach of hoses on the train?

Yes, But if it keeps the fire away from the railway that could still be most useful. No damage to OHLE, or signalling cables etc.

[IndustryInsider]

I would assume in such cases all the resources go into stopping fires from spreading and preserving life rather than hopefully saving a bit of signalling cable.  Given the speed some fires spread I also don't think I'd like to be one of the firemenfighters stood on the wagon, even if I had a plentiful supply from my hose!

One of your less sensible ideas IMHO^▸ (in my humble opinion), broadgage!

[stuving]

Given the speed some fires spread I also don't think I'd like to be one of the firemenfighters stood on the wagon, even if I had a plentiful supply from my hose!

The same danger exists for those in road vehicles too, where one of the most serious hazards is being surrounded by a fast-moving fire. So in France the front-line vehicles contain a big tank (500 l, in addition to any fire-fighting supply) of water which is sprayed on the outside (and tyres) to keep the inside survivably cool for a few minutes. That works because the risk is from a fast-moving fire, which moves on quickly too.

The only real use I can think of for rail in support of fire-fighting is to bring in water to refill vehicles' tanks.

[TaplowGreen]

Some of the large fires near the railway in France and perhaps elsewhere could have been fought from a train.  A train of water tankers can carry a vast amount of water, perhaps a thousand tons as compared to a few tons carried by a fire engine.

Start with say ten tank wagons, and between each pair of tanks place a suitable open topped wagon with sides about 1.2 meters high. Each wagon to contain a couple of portable engine driven fire pumps and two firemen. Connect the pump suction to the tank outlet, and the pump discharge to a short length of standard fire service delivery hose.

Firefighting from the top of the water tankers is obviously not applicable to routes with OHLE, but from a suitable wagon should be ok.

https://youtu.be/QrrIRr9arkM

[froome]

There have been some phenomenally high overnight temperatures which will have obliterated many local records, particularly in Wales and the west. A minimum of 26 degrees here in Bath by the looks (and feel) of it, and the Met Office site shows minimums of 27 along parts of the west Wales coast. Fortunately here in most of GWR^▸ (Great Western Railway) land, we are 'only' likely to reach maximums in the lower 30s today, but the eastern side of the country, and especially the east Midlands, is going to be cooking. I doubt whether anything will be moving there, whether it be by rail, road or foot.

On the subject of transporting water, rail is very efficient at distributing bulky, heavy objects, and should be ideal for moving it around, but obviously suffers from the inflexibility of only reaching certain places, which are unlikely to be where it is needed. And do we have the rolling stock to do it? I'll let you experts answer that for me.

Transporting water by lorry into areas that are savagely hot is likely to end up with the lorry sinking into melted tar, having half destroyed all the roads along the way with its weight.

[GBM]

Thunder, lightning & heavy rain down far West

[GBM]

Cancellations to services between Penzance and St Erth
Due to lightning damaging the signalling system between Penzance and St Erth all lines are blocked.
Train services running to and from these stations may be cancelled, delayed or revised. Disruption is expected until 10:00 19/07.

Alterations to services between St Erth and St Ives
Due to lightning damaging the signalling system disruption is expected until 09:15 19/07.
Train services between St Erth and St Ives have been suspended.

Now updated 10;15
Alterations to services between Penzance and St Erth
Due to lightning damaging the signalling system between Penzance and St Erth fewer trains are able to run on all lines.
Train services running to and from these stations may be delayed or revised. Disruption is expected until 12:00 19/07.