Largest UK locomotive

[edwin_m]

Part of the issue was need for heavy locos due to widely used unfitted freights so wasn't much incentive to reduce weight considerably.
Warships also used monocoque technology whereas early British designed diesels were based around a frame. They also used high speed engines as opposed to heavy medium speed engines.

And yet I believe the class 40, whose power to weight ratio was very much biased to he latter, was known for not having very good brakes!

 

[harz99]

I always had the impression that class 55 Deltic type locos were the largest diesels in use...

 

[Richard Scott]

And yet I believe the class 40, whose power to weight ratio was very much biased to he latter, was known for not having very good brakes!

They certainly had considerably less brake force than a 45.

 

[Magdalia]

And yet I believe the class 40, whose power to weight ratio was very much biased to he latter, was known for not having very good brakes!

They certainly had considerably less brake force than a 45.

The the wheels on the unpowered axles are braked on a BR Type 4 but not on an EE Type 4.

 

[norbitonflyer]

I always had the impression that class 55 Deltic type locos were the largest diesels in use...

Most powerful at the time (not equalled until class 58 and 59, not exceeded until class 70), and at 69'6" the same lenghth as a Class 40, but not the heaviest (99 tons).

 

[D7666]

Most powerful at the time (not equalled until class 58 and 59, not exceeded until class 70), and at 69'6" the same lenghth as a Class 40, but not the heaviest (99 tons).

What about HS4000 then - is that excluded for some reason ?

 

[Richard Scott]

The the wheels on the unpowered axles are braked on a BR Type 4 but not on an EE Type 4.

No, neither were so unsure why there is such a large difference. Guessing brake cylinders on a 45 etc are able to apply more force. There are 24 of them and they are big beasts!

== Doublepost prevention - post automatically merged: 23 Aug 2024 ==

Most powerful at the time (not equalled until class 58 and 59, not exceeded until class 70), and at 69'6" the same lenghth as a Class 40, but not the heaviest (99 tons).

Light high speed engines in a Deltic and I believe they used stressed construction techniques rather than having a heavy frame like other locos?

 

[Magdalia]

No, neither were so unsure why there is such a large difference.

Thanks for that. Comparing more widely, the EE Type 4 looks like it is the outlier.

 

[Spaceship323]

What about HS4000 then - is that excluded for some reason ?

Not the heaviest ~ only 133 tons, Not the longest ~ only 20.27m, quite powerful at 4000hp but the OP's question was "which is the largest"

 

[Richard Scott]

Thanks for that. Comparing more widely, the EE Type 4 looks like it is the outlier.

I know we're in danger of drifting but 40s were really just 10203 without any real mechanical improvements. I believe EE offered to uprate them to 2400hp in later builds but BR declined as wanted reliability. To be fair, they may have been big and heavy but we're pretty bulletproof. I understand it was rare for one to fail.

 

[D7666]

Not the heaviest ~ only 133 tons, Not the longest ~ only 20.27m, quite powerful at 4000hp but the OP's question was "which is the largest"

I was not responding to the OP question.

The comment to which I was responding was what I quoted -

Most powerful at the time (not equalled until class 58 and 59, not exceeded until class 70), and at 69'6" the same lenghth as a Class 40, but not the heaviest (99 tons).

HS4000 exceeded all of that lot , 55 58 59 and 70.

And BTW, it was not really 4000 hp. There are horsepowers ad there are horsepowers and not all horsepowers are equal. If one is talking about 40 / 58 as 2000 / 3300 hp then Kestrel was 3946 hp (rounded) not 4000 hp.

 

[Thames99]

Stretching the OP's definition a bit, were there any locomotives that were routinely used in pairs? These could well exceed the weight and length of the suggestions above.

 

[D6130]

Stretching the OP's definition a bit, were there any locomotives that were routinely used in pairs? These could well exceed the weight and length of the suggestions above.

Yes....classes 17, 20, 21, 24, 25, 26, 27 & 28.

 

[norbitonflyer]

What about HS4000 then - is that excluded for some reason ?

I forgot HS4000, but in mitigatiuon, it was never owned by BR or given a class number.

== Doublepost prevention - post automatically merged: 24 Aug 2024 ==

Yes....classes 17, 20, 21, 24, 25, 26, 27 & 28.

Not to mention class 42 on the Cornish Riviera Express.

The 66/73 combos on the Caledonian Sleeper probably top most of those though!

 

[Magdalia]

Stretching the OP's definition a bit, were there any locomotives that were routinely used in pairs? These could well exceed the weight and length of the suggestions above.

Class 37s were used in triples on the Llanwern iron ore trains.

 

[ac6000cw]

Class 37s were used in triples on the Llanwern iron ore trains.

Over 300t and over 55m long (and 5250hp) in total!

 

[Steve Harris]

I always had the impression that class 55 Deltic type locos were the largest diesels in use...

I was thinking the same thing !

It does seem that some posters should of checked a dictionary first before posting though...
According to the Oxford English Dictionary...
large
adjective
superlative adjective: largest

of considerable or relatively great size, extent, or capacity.

Which to me means physical size, and has nothing to do with weight (as the question would of been what's the heaviest...)

Perhaps we need the OP to clarify??

== Doublepost prevention - post automatically merged: 24 Aug 2024 ==

Most powerful at the time (not equalled until class 58 and 59, not exceeded until class 70), and at 69'6" the same lenghth as a Class 40, but not the heaviest (99 tons).

What is the difference in height though ?

As I posted above, weight (and power) is a red hearing.

 

[D7666]

I was thinking the same thing !

It does seem that some posters should of checked a dictionary first before posting though...
According to the Oxford English Dictionary...
large
adjective
superlative adjective: largest

of considerable or relatively great size, extent, or capacity.

Which to me means physical size, and has nothing to do with weight (as the question would of been what's the heaviest...)

Perhaps we need the OP to clarify??

..................
As I posted above, weight (and power) is a red hearing.

Maybe.

But there is such a thing as thread digression.

No thread ever will keep to the precise exact OP wording - especially where that wording is open to interpretation.

Now, taking your OED quote, there can be

large power
largest power
considerable power
relative power
great size of power
extent of power
power capacity

as well as any other physical attribute e.g.

largest weight
largest height
largest width
largest number of wheels
largest number of engine cylinders

and so on and on

Neither the OED nor anywhere impose limits on what adjectives comparatives and superlatives refer to. If you believe so, "it does seem then" then further to your suggestion that posters should refer to dictionaries that you need to read some English grammar references.
_

I forgot HS4000, but in mitigatiuon, it was never owned by BR or given a class number.

Since some upthread seem to think we need to stick to the OP wording, I will point out there was no OP reference about ownership or class number.

BR was never mentioned by OP. Only "UK" and "domestic".

If we are to stick to BR class ownership, then your references to 59s and 70s are invalid, since neither were ever owned by BR.

You see, things are open to interpretation by anyone.

QED.

_

There are literally 100s and 100s of double headings you get at least

03
08
15
16
17
20
21
22
24
25
26
27
28
29
30
31
33
35
37
40
42
43
45
46
47
50
56
58
59
60
66
67
68
LMS 1000x
SR 1020x

that I can right away think of examples - and I am sure with those I omitted e.g. 70 52 44 23 there must have been some I just can't think of any right now.

So now add up all the mixing of different classes...........................
_

Triple heading :

42/43 + 2x22 WR in Devon and Cornwall
40 + 2x24/25 LMR at least
40/47 + 2x26/27 ScR north of Perth at least
3x50

and, since we are at it,

4x50 WR booked at least once - and it did happen.
4x20 1970s Toton coal


QED on thread drift too.

 

[Steve Harris]

Hence why I said

Perhaps we need the OP to clarify??

As that would take out any misinterpretation !

 

[norbitonflyer]

largest number of engine cylinders

and so on and on

Almost certainly the Deltics, with 2x18=36 cylinders (and 72 pistons!)

 

[xotGD]

Nothing larger than a no-heat 37 chucked out on a passenger turn.

 

[Richard Scott]

Nothing larger than a no-heat 37 chucked out on a passenger turn.

I don't know a pair of large logo 56s on a passenger train (admittedly part of an organised day) must go down as one of the largest I had!!!!

 

[D7666]

re double heading exceeding single loco

that one is easily addressed - once "the largest" has been identified by whatever restrictions one wants to utilise, then obviously two of those "largest" double heading is automatically bigger than both one or two of anything else.

/apart/ from very few examples of solo types there is no need to consider double heading

 

[CW2]

I know we're in danger of drifting but 40s were really just 10203 without any real mechanical improvements. I believe EE offered to uprate them to 2400hp in later builds but BR declined as wanted reliability. To be fair, they may have been big and heavy but we're pretty bulletproof. I understand it was rare for one to fail.

Because of their heavy weight and relatively low power (compared to other type 4s), class 40s spent a lot of time moving quite slowly but on full power. As a result the cooling system was a bit marginal, especially in hot weather, so failures due to overheating or coolant leaks were the main weakness.

 

[D7666]

Nothing larger than a no-heat 37 chucked out on a passenger turn.

I had been waiting for someone to post something like this and refraining from doing so myself.

IMHO the largest ever I had was 20203+20204 out of NewSt on 1E63 when they were nominally HA engines but outbased at TJ - this was years and years before they were re-allocated south of Hadrians Wall whereupon they merged into the Toton whirlpool, and, before someone adds it, it was many years after they had been used from YK on Scarborough etc trains. 1E63 working was in their "large" huge period.

_

Because of their heavy weight and relatively low power (compared to other type 4s), class 40s spent a lot of time moving quite slowly but on full power.

Not sure that 'slowly' is true of their early days when they were essentially operating the entire WCML express passenger work pre-25 kV.

 

[CW2]

Not sure that 'slowly' is true of their early days when they were essentially operating the entire WCML express passenger work pre-25 kV.

Well, class 40s were faster than the steam locos they replaced on WCML services, but "express" is a suitably vague term. Reaching 90mph with 12 Mk1s behind relied heavily on wishful thinking and the curvature of the Earth.

 

[D7666]

Well, class 40s were faster than the steam locos they replaced on WCML services, but "express" is a suitably vague term. Reaching 90mph with 12 Mk1s behind relied heavily on wishful thinking and the curvature of the Earth.

Class 1 then ?

Despite what the ravings of O S Nock and co will have you believe, I kind of get the impression general day to day WCML running in kettle days was rather a lot of smoke and noise and not a lot of speed, and D200s merely moved slightly faster with different noise. Likewise D5000s on Class 2s.

Burt we'll have to stop this thread drift or we will be told off for not answering the OP precise wording.

 

[sprinterguy]

Nothing larger than a no-heat 37 chucked out on a passenger turn.

Now that's properly large.

== Doublepost prevention - post automatically merged: 24 Aug 2024 ==

Class 1 then ?

Despite what the ravings of O S Nock and co will have you believe, I kind of get the impression general day to day WCML running in kettle days was rather a lot of smoke and noise and not a lot of speed, and D200s merely moved slightly faster with different noise. Likewise D5000s on Class 2s.

Burt we'll have to stop this thread drift or we will be told off for not answering the OP precise wording.

A D200 would, on paper, shift you slightly faster on the flat or slightly upgrade for an extended period than a Coronation Pacific, but the Coronations could briefly develop higher drawbar horsepower figures, sometimes by mortgaging the boilers' ability to produce steam for short periods, on the banks that the D200s couldn't match.

Hence the later use of of D400s singularly, and in pairs on critical services, north of Preston pre-electrification.

In general, though, I agree that "a lot of smoke and noise and not a lot of speed" is a fair analogy of the steam era in general.

 

[Deepgreen]

(Almost) amusing that the thread has descended, via numerous deviations, into seeking OP definitions - the OP's "general size" is clear enough to me - meaning physical dimensions; therefore not power, tractive effort, whether worked in pairs, etc.

 

[Trackman]

Class 1 then ?

Despite what the ravings of O S Nock and co will have you believe, I kind of get the impression general day to day WCML running in kettle days was rather a lot of smoke and noise and not a lot of speed, and D200s merely moved slightly faster with different noise. Likewise D5000s on Class 2s.

Burt we'll have to stop this thread drift or we will be told off for not answering the OP precise wording.

There was a performance report D200's vs kettles, didn't bode well for the 40's if I remember.