GBRf Class 99 - 30 locomotives now ordered

[12LDA28C]

Thank you.
Let's do the numbers. The gradients up to Exeter Central is 1.5% and 2.7%, rising 40m in all.

In round numbers, the eight-car Western sleeper will weigh ~325t. With loco that will be around 400t. To get up the steepest 2.7% slope will require a tractive effort of 110kN. Well within the 290kN capability of a 93. A 99 would be overkill.

On diesel and battery, the 93 generates 1300kW. Allowing 500kW for hotel power gives 800kW for traction, which equates to a speed of 800/110 = ~7m/s up 2.7%. That's 15mph, which should be acceptable late at night. A 1600kW Class 99 would not be much faster.

800kW can lift 400t up 40m in 200s, so the 93 will take 3 1/2 mins to get to Exeter Central. Meaning the batteries will still be three-quarters full at the top.

The biggest hill on line BAE2 is between Cranbrook station and Honiton tunnel, which rises 130m over 20km. Averaging the gradient to 0.65% gives a speed of 800kW/26kN = ~30m/s, around 65mph, ignoring wind and rolling resistance. Taking 660s = 11 minutes to cover 20km. Battery capacity is enough to deliver full power all the way up, but would be exhausted at the top.

Back on topic, a Class 99 woud be overkill for the sleeper, even if it had hotel power. The 99 will be much better suited to hauling heavy aggregate trains from the Mendips to London, or max length 1800t intermodals up the hill from Felixstowe, where the 500kN tractive effort would be put to good use.

Line profile and gradient data from: https://www.railwaydata.co.uk/linefiles/route/?ELR=BAE2

What is the relevance of any of this given that we seem to have established that nothing will be replacing the 57s on the Night Riviera any time soon?

 

[Nottingham59]

We seem to have established that nothing will be replacing the 57s on the Night Riviera any time soon?

Post #293 says that GWR are looking to do just that.

For the longer-term, GWR is looking for Class 57 replacements, with the Class 99 bi-modes due to be delivered to GB Railfreight exciting some interest. “Whatever we end up getting for the sleeper, the new loco will have to be able to use overhead electric, with one benefit being we can get out of using diesels in central London’ says Mr Hopwood. 'It'll need to be powerful enough to haul nine or 10 coaches up the steep bank between Exeter St David's and Central, because the sleeper is frequently diverted over the South Western to avoid overnight engineering works. And it'd be useful to be able to get in and out of Long Rock depot on battery power, as we'd like to reduce noise for local residents there”

 

[12LDA28C]

Post #293 says that GWR are looking to do just that.

Ah, I missed that although surely this is many years away given the major exam/overhaul program which has been started on the Class 57s.

 

[Deepgreen]

Hope they can afford this on their wafer thin margins.

Anyway, that's enough cornet jokes.

They will also have to be adorned with red balloons for safety reasons (have I gone too obscure, I wonder...).

 

[ExRes]

They will also have to be adorned with red balloons for safety reasons (have I gone too obscure, I wonder...).

Do we have to admit to remembering that far back?

 

[12LDA28C]

Do we have to admit to remembering that far back?

1984?

 

[Wyrleybart]

There is and never was a plan to use these on the Night Riviera.
The G Exam program currently underway will basically result in a new 57 .

Really ? How do you turn a 60 year old loco body, 60 year old bogies and 25 year old traction alterrnator into a new loco ? If the works guts each locomotive shell of every single pipe and cable, then installs brand new looms , pneumatics and ancillary equipment, then maybe you can aspire to i. I remember a HST power car sitting down on a remote part of the "desert" with a fractured air pipe in the van end, causing much grief. That could have been 10-15 years newer than a 57.

Not criticising the 57s because they are not computer controlled so are able to turn in good availability, but are still materially aged.

 

[Snow1964]

They have their own page within the fleet section of Beacon Rail website

CL.99 - We lease passenger and freight rolling stock across Europe

beaconrail.com

Says power 1790kW, 120km/h (75mph) top speed with tractive effort of 500kN, weight is 113t

For comparison the class 88 is 4000KW (electric) and 700kW (diesel) and tractive effort is 317kN

Class 66 is 2400kW power (but nearer 1850KW at rail), weighs 129t and tractive effort is 409KN

 

[MikePJ]

That 1790kW figure must be in diesel mode - the quoted specs when they were ordered was for 6000kW on electric.

 

[ac6000cw]

A news article in the June 2022 Modern Railways said the Class 99 diesel engine will be a Cummins QSK50 rated at 1800kW (2413hp).

The rating on the Beacon Rail webpage is presumably the 'at the crankshaft' diesel engine rating (which is normal/traditional for European diesel locos). Usual rule-of-thumb is to reduce that by 10% to 20% - depending on electric transmission efficiency - to get a rough power-at-rail rating.

So on diesel power it's a low-end 'Type 4' (in terms of power-at-rail) and on electric the most powerful loco ever built to run on the BR/NR system - Jekyll and Hyde?

 

[sh24]

So basically a Class 40 and a turbocharged 92 in one loco. Quite something.

 

[Snow1964]

So basically a Class 40 and a turbocharged 92 in one loco. Quite something.

More than double the tractive effort of a class 40

 

[Nottingham59]

More than double the tractive effort of a class 40

And it's the tractive effort that matters.

The great thing about the 99 is that the busiest lines with the most congestion are nealy all electrified, where 6000kW will find slots in the timetable that a Class 66 or 70 wouldn't. For instance, a 99 should be twice as fast up Shap or Beattock as a 66 or 70.

Away from the wires tends to be less pressure on the timetable, so peak power is less important as you would usually be able to take a bit longer to get up a gradient, or shunt into a freight terminal.

I can only find a few places without OHLE on the network where performance uphill is going to be critical for timetabling a freight locomotive. The most important are the hill up from Felixstowe, and the hill up from Dore to the Bradway tunnel (though that is due for electrification at some point). No doubt people will know of others.

 

[ac6000cw]

So basically a Class 40 and a turbocharged 92 in one loco. Quite something.

On diesel, it should better a cl. 47 in power terms (a bit less engine power but more efficient transmission) but with around twice the low-speed tractive effort and much better wheelslip control.

On electric, the power output might also be limited by how much power it can draw from the OHLE e.g. AFAIK the pairs of cl. 90s that FL use are modified to limit the total power draw to about 1.5 times a single cl. 90.

 

[Peter Sarf]

And it's the tractive effort that matters.

The great thing about the 99 is that the busiest lines with the most congestion are nealy all electrified, where 6000kW will find slots in the timetable that a Class 66 or 70 wouldn't. For instance, a 99 should be twice as fast up Shap or Beattock as a 66 or 70.

Away from the wires tends to be less pressure on the timetable, so peak power is less important as you would usually be able to take a bit longer to get up a gradient, or shunt into a freight terminal.

I can only find a few places without OHLE on the network where performance uphill is going to be critical for timetabling a freight locomotive. The most important are the hill up from Felixstowe, and the hill up from Dore to the Bradway tunnel (though that is due for electrification at some point). No doubt people will know of others.

I expect it is not very likely but with the Lickey incline electrified could that mean a 99 working between Bristol and the North ?.

It is making me think discontinuous electrification but taking in the sharper gradients could fit the class 99s capabilities at least on freight.

 

[Rail Quest]

Do we know (or have a way of calculating) at what speed the TE of a 99 on diesel will be equal to that of a 66? My thinking is that it should therefore be relatively simple to predict what routes/flows the locos could operate with negligible impact when compared to sheds.

 

[Speed43125]

The great thing about the 99 is that the busiest lines with the most congestion are nealy all electrified, where 6000kW will find slots in the timetable that a Class 66 or 70 wouldn't. For instance, a 99 should be twice as fast up Shap or Beattock as a 66 or 70.

And more than that of pair of 90s as well, which is very impressive. 500kN compared to 2x258kN that's in practice limited by only having 6 of the 8 traction motors running.

 

[The exile]

I can only find a few places without OHLE on the network where performance uphill is going to be critical for timetabling a freight locomotive. The most important are the hill up from Felixstowe, and the hill up from Dore to the Bradway tunnel (though that is due for electrification at some point). No doubt people will know of others.

I imagine routes / paths out of Southampton (particularly on the Main Line) could be an issue on diesel power.

 

[BRX]

I wonder if they'll get cleared for 3rd rail land & used on routes that in a better world would still be done by 92s.

 

[Nottingham59]

I expect it is not very likely but with the Lickey incline electrified could that mean a 99 working between Bristol and the North ?.

Lickey is 1 in 33, so a 1000t intermodal needs 30t=300kN of tractive effort. At 6000kW on AC, that alllows a speed of 20m/s up the hill = 45mph. Is that fast enough to keep out of the way of following passenger services? I would have thought so.

Do we know (or have a way of calculating) at what speed the TE of a 99 on diesel will be equal to that of a 66? My thinking is that it should therefore be relatively simple to predict what routes/flows the locos could operate with negligible impact when compared to sheds.

Around 10mph?

From the class 93 thread, have a look at the TE-speed charts for class 66 and 93, on the left.

https://www.railforums.co.uk/attachments/class-93-versus-67-te-png.159059/

On diesel, the class 99 has more power than a 93, and less than a 66. So in the curvy bit of the graph, the 99 will lie above the 93 curve and below the 66 curve. It will only cross over the 66 curve at slow speeds, when the tractive effort of the 66 cannot exceed 420kN. That looks to me at around 10-15mph, by eye. But above this speed, the class 99 has 1600kW at the rail, compared to the class 66's 1850kW at the rail. So it won't be all that slower to climb hills off the wires. My thinking is that it is only on the busiest lines that this will matter much.

I imagine routes / paths out of Southampton (particularly on the Main Line) could be an issue on diesel power.

I can see that. Particularly up to Micheldever at 150m ASL. Going via Andover would be much gentler.

 

[sh24]

On diesel, it should better a cl. 47 in power terms (a bit less engine power but more efficient transmission) but with around twice the low-speed tractive effort and much better wheelslip control.

On electric, the power output might also be limited by how much power it can draw from the OHLE e.g. AFAIK the pairs of cl. 90s that FL use are modified to limit the total power draw to about 1.5 times a single cl. 90.

I'm not an engineer so its fascinating to understanding the capability of the 99. Quite a beast!

 

[Meerkat]

Lickey is 1 in 33, so a 1000t intermodal needs 30t=300kN of tractive effort. At 6000kW on AC, that alllows a speed of 20m/s up the hill = 45mph. Is that fast enough to keep out of the way of following passenger services? I would have thought so.

Does Lickey have enough juice for that, as it was built for relatively short EMUs??

 

[Snow1964]

Does Lickey have enough juice for that, as it was built for relatively short EMUs??

Some of the tracks in the area are also not electrified, so a class 99 would possibly not be able to run unrestricted on electric.

 

[66701GBRF]

MD John Smith briefly talking about the 99.

 

[D365]

I wonder if they'll get cleared for 3rd rail land & used on routes that in a better world would still be done by 92s.

I’m not aware that the Class 99s will have third rail pickup.

 

[XCTurbostar]

MD John Smith briefly talking about the 99.

"She's a bit of a beast" - John Smith 2024

 

[Nottingham59]

Does Lickey have enough juice for that, as it was built for relatively short EMUs??

I really wouldn't know. When the 99 hits the tracks, there are going to be all sorts of places that turn out not to have enough juice. I wonder if it can use the diesel to supplement the AC supply if there are limitations on AC power draw?

== Doublepost prevention - post automatically merged: 25 Sep 2024 ==

EDIT:
John Smith is saying the 99 is designed to match the timings of a 66 up from Felixstowe to Ipswich. Despite the lower power on diesel, it's greater tractive effort at slower speeds means that it can put as much power down at the rail as a 66.

That's really good news. He clearly sees the 99 as being a replacement for the 66, starting with routes where they run distances under the wires.

 

[BRX]

I’m not aware that the Class 99s will have third rail pickup.

They don't, but the industry seems to have given up on using 3rd rail power for freight operations. On the routes that previously used 92s, it would be better to have a loco that used diesel on the 3rd rail section, then electric on the OHL section, than what we have at the moment, which is diesel all the way.

 

[Peter Mugridge]

Does Lickey have enough juice for that, as it was built for relatively short EMUs??

Don't the wires stop at Bromsgrove anyway, so anything on electric has to start from there at 0 mph...?

 

[Nottingham59]

Don't the wires stop at Bromsgrove anyway, so anything on electric has to start from there at 0 mph...?

It's all moot anyway. The 99s are going to be used first on flows with substatial running under the wires. There's plenty of opportunites on the WCML/ECML/MML/GEML before looking at routes to Bristol and beyond.