flare40x Tue, Aug 6 2013 1:55 PM
>> such as the French 241P (postwar four-cylinder compound Mountain type, built in a series of 35) or the experimental three-cylinder 242A1 Northern (designed by Chapelon during the war) which were far more sophisticated and far more efficient than anything ever built in the US. <<
The 241.P certainly not . They were old PLM 241.C.1 revisited and – after the SNCF HQ had denied the 242.A.1 to be series contracted , Chapelon as head of the DEL ( Division des Étude de Locomotives ) was asked to ‘improve the PLM-C.1’ – how cynic can you get ? The 242.A.1 although but a rebuilt loco type was by far better all around than the rather mediocre 241.C.1 . However , the old PLM gangs had taken over when SNCF was founded and so they over-ruled Chapelon’s designs . The C.1 was a prototype just as the A.1 , however in contrast to the latter had been out of date by the time it appeared and as a Mountain type had not even been competitive to the Paris-Orleans-Midi Chapelon Pacific when taking part in the NORD railway comparison tests . The PLM when stepping up from four cylinder Pacifics to Mountain type had tried various rather weird drive dispositions : to avoid by all means to have a dual crank axle as first coupled , they had outside LP cylinders drive on first , inside HP drive on second . Then , since these locos , 241.A and .B , were clearly less than successful – example of technical near-failures still long lived thanks to substantial series production and hence indispensability – they tried various other concepts with rebuilds of these 'cigarres' as they were called into 241.D and .E until ending up with the 241.C.1 ( C after E - *g* ) having inside HP driving on third ( !! ) coupled axle only to make outside LP drive on second , the loco *looked* quite regular on the outside – if at the expense of pretty messy inside drive arrangement . So , this awkward loco prototype was preferred by SNCF HQ to the 242.A.1 which by then had passed about any examine an express steam locomotive could have been asked for on the SNCF – now if that wasn’t a mindboggling decision then I have a bridge in Brooklyn ! And to improfumble it from wanting to so-so , Chapelon was asked to apply his wisdom – the materialization of which in shape of the 242.A.1 had been turned down – although , and now it becomes really weird , upon test runs on their mainline passed with flying flags the Region Ouest ( ‘Lines West’ in PRR parlance ) had already asked for at least 25 to be urgently built as they had been void of Mountain type engines when they had to send their ETAT 241 – copies of the EST 241.A – to the East . As a matter of fact , the only replacement the Western Region ever saw for Mountain types gone East were a contingent of 141.P Mikados , and that only came to be after the former PLM ‘Ligne Imperiale’ had been electrified and the South-Eastern Region-HQ had no more useful work for them . As I had remarked earlier , the 141.P were valiant dual purpose engines – however they were far from capacities of a Chapelon 240.P - let alone the 242.A.1 .
So , what we have here imho is a typical example of ‘one being too good’ .
Framework for three cylinder compound engines :
Btw – I have meanwhile been able to take a look at drawings of the Chapelon three cylinder compound 152 ( 2-10-4 ) already started to be constructed : as I had suspected the engine does *not* feature a cast steel one-piece engine bed but a fully welded frames structure – one piece , too , when finished – however much lighter than the cast steel structure and thus better suited for European axle load limits plus for construction in the absence of highly specialized works able to handle such large pieces plus , last not least , cheaper to build with small numbers of engines .
However the owner of the copies does not want to see them scanned and uploaded so I respect his wish and all I can show is p 399 of the book ‘La Machine Locomotive’ by Sauvage / Chapelon which down below shows an example of the welded sandwich framework planned for the Chapelon engines ( # 6 of drawings ) above ( # 4 ) is an example of cast steel one piece engine bed btw is that of the one and only Sally-One .
Various types of frames ; # 6 all welded structure proposed for high performance engines to be built post 1950
( from : Sauvage / Chapelon - La Machine Locomotive )
PLM 241.A 'Cigarre' ( so nicknamed because of the paraboloid smokebox front cover ) ~ 55 sqft grate plus combustion chamber ; inside HP cylinders drive to second coupled axle , note receiver pipe coming out from frames backwards of LP cylinder ; bolted made up plate frames ; low running board was PLM sine-qua-non style
241.C.1 offspring SNCF standard 241.P - in Clermont-Ferrant in 1968 - note faily clean engine for last summer of regular working , although SNCF dull green has become tolerably blackish - tone-in-tone with originally black and metal , now but oily wheels and rods .
242.A.1 on yet another test run - now on the Western Region ; although having asked for 25 to be built , the Region never again was to have high wheeled eight coupled express steam locos after their 241.A had to be sent East ; the only eight coupled power they - later - got was ..
.. a late batch of 141.P , increasing in engine numbers as they came as surplus from other regions ; for many years regular dual purpose power at LeMans , heading heavy express trains in plans including the 242.A.1 ; here at Argentan , one last stronghold of the engines - note again clean engine in spite of common user running close to end of service .
Regards
Juniatha
Drawings of frames now included in previous posting -
plus photos - check it out .
= J =
Yes , please really *do* check it out - can you see all the photos ? or which one is missing ? I 'saw' the 241.P was missing lately .. well as I wrote : last summer of service .. *g*
In case there should be any objections to my posting these pictures here please let me know - thank you .
Thomas, for the purpose of discussion, why?
Crandell
The Reading was still building new steam locomotives after WWII. Both 4-8-4s and 4-6-2 were built in Reading Shops during that time.
As for the main thread of this forum, these comparisons miss the point that modern steam locomotives were built for specific situations. I can "PROVE" that New York Central's Niagaras were better locomotives than both the Norfolk & Western J and the Southern Pacific GS4. No way you say!!! Lets go back to the early 50's at Harmon NY and put a Niagara on the first section of the 20th Century Limited, then put the J on the second section and the GS4 on the 3rd . All three sections are identical in weight and drag Which one gets to Chicago with the highest average speed? It is no contest, the Niagara wins hands down. Both the J and GS4 will be piles of junk at the first tunnel on the NYC. They do not fit the clearance!!! So how can you say that they are better locomotives when they cannot compete in the service that another performs so well at. The clearance on the NYC was so tight that the Niagaras didn't even have steam domes, they used dry pipes at the top of the boiler instead.
... well ... of course every engine needs the permanent way adequate to it - this applied in steam times as it applies today .
This way you could 'prove' direct current electrics are better than three phase synchronous electrics if you raise the pantograph of the latter under 3000 V DC ...
Or vice versa
A diesel-electric is better than a straight electric on track without overhead wiring and so on and so forth .
Yet , it's cute : *any* steam locomotive is better than any diesel when assigned to a roundhouse just providing coal , water and steam loco classified grade of lube oil .. a diesel just can't crunch coal of any grade and size .
Last not least , my bike is better than a Cadillac in the absence of gas - *g*
No insult intended ..
DS4-4-1000Both the J and GS4 will be piles of junk at the first tunnel on the NYC.
timz DS4-4-1000Both the J and GS4 will be piles of junk at the first tunnel on the NYC.Offhand guess: none of the NY Central tunnels on the main line were that low. Question is, were any overhead bridges on the main that low? Maybe so-- anybody know which one?
Well, if the GS-4 and the Mighty 611 were turned into piles of scrap metal at the first NYC tunnel it wouldn't have been the locomotives fault. It would have been the fault of the guy who turned them loose on the mainline without using a tape measure first!
Look, for some people, the best locomotive in the world is the PRR GG-1. I might argue that that the New Haven's EF-3a (modified with steam boiler for passenger service) could outpull and outrun it, which it indeed could, and that the engineer's controls were easier to use, the cabs more comfortable, etc. but the beauty of the design will allow my friend to still claim the GG-1 the best. Of course the EF-3a never really had a chance on the limited Penn Station - New Haven run to show its stuff. (But it did handle 100+ car trains on the grades to Hell Gate Bridge, which would have required two GG-1's and needed four GP-9's post-McGinnis, then two of the ex-Virginians.) Then a real New Haven dyehard will challange me by saying, "Yes, but the EF3a could not run into Grand Central Terminal, while the similar looking (and almost as well performing) EP-4 could, so the EP-4, almost identacle in carbody design, is the better.
So everyone is entitled to his opinion. I count looks. So the J is my favorite. With Daylight second choice, and then hard to choose between a Ripley 4-8-4 and the Niagara.
I think that you miss my point. These comparisons are meaningless because they do not account for the restrictions placed on the designers due to clearances, bridge weight restrictions, vertical and horizontal curvature, etc. Just because one particular locomotive has a higher horsepower, tractive effort, or top speed does not necessarily make it a superior locomotive unless you are making comparisons to another in the identical service. My point with the Niagara is that even though the N&W and SP machines could pull more, and probably faster, they are unable to accomplish the duty for which the Niagara was well suited. As with my Niagara, J, GS comparison since they are designed for different services by choosing what I determine is important I can make any one of them "THE BEST".
Another example of this thinking is the threads where the PRR is villified for not adopting a variant of the N&W A which the Pennsy tested. This thinking totally ignores the slipping problems PRR experienced during the testing caused by the compensated grades the PRR right of way has in abundance. N&W also compensates some grades but had far fewer vertical curves than did the Pennsy and I suspect that the changes in the gradient on the N&W are less severe than on the PRR.. Expecting the Pennsy to completely regrade its mainlines is unrealistic as is expecting the CMO to accept a design which showed significant problems when tested.. Pennsy decided on the rigid frame Q2 partly because it did not have the slippage problem with the compensated grades. Yes the Q's had maintenance problems but they were well liked by the crews and when they ran performed well.
DS4-4-1000the slipping problems PRR experienced during the testing caused by the compensated grades
timz Was it a problem for N&W's siderod electrics on the 1.4% compensated climb that N&W built circa 1950?
Was it a problem for N&W's siderod electrics on the 1.4% compensated climb that N&W built circa 1950?
Locomotives with electric traction motors have a distinct advantage over traditional steam when it comes to traction on grades. Besides, 1.4% isn't much of a grade...
GP40-2 timz Was it a problem for N&W's siderod electrics on the 1.4% compensated climb that N&W built circa 1950? ... Besides, 1.4% isn't much of a grade...
... Besides, 1.4% isn't much of a grade...
If I understood Al Krug's article on HP/grades, it would require the application to the drawbar of approx. 9 times more horsepower to lift a train on a 1.4% grade over that on perfectly level track. Would such a circumstance not encourage a slip on the 'right' vertical curve?*
*Assuming the four sets of drivers had enough adhesion to apply the increased hp to the rails in order to maintain reasonable fwd momentum.
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