I recall an issue in the PRR Railroad Historical Sociiety where they speculated about the R-1 a PRR 4-8-4 locomotive. They had rought drawings of what it might have looked like.
Do you mean the Vol.33, #3 issue of The Keystone?" There were elevations of "what-if" PRR 4-8-4's ca 1929 and 1942 . See pgs 52-55.
The drawings offered in the Keystone article are most interesting and inspiring to steam loco lovers . Uhm .. yet how did this article say anything about the M1 Mountain supposedly having been equal to 'a' (? which one) 4-8-4 ? Equal to one certain not-so-super 4-8-4 maybe (choose our own) , still that had never been an issue at the time when the class was being designed not could it have been . On an equal theoretical basis (like : same engine mass per wheel and consequently differing limits of grate size to name it) , no Pikes Peak mountain of a 4-8-2 could be a match for a Northern type in power output simply for lacking that odd pair of wheels that makes for a four-eight-four in the latter type and not just under Northern Lights .However , with varying quality of design all sorts of relative power outputs could and were achieved : just to name Milwaukee's Hiawatha A class Atlantic in really upper speed range outperforming most Pacifics of equal adhesion mass per drive wheel (note: wheel not total !) ...At her time Pennsy's M1 was a formidable performer , especially on mountainous (!) lines and on heavy loads , less so the more speed became a vital part of demands - that's why these engines stood very heavy duty in freight train running, effectively working as 'another form of a Berkshire' as to characterize their output range, with a degree of advantage over most 2-8-4s in the (mild) upper speed range, say 50 - 60 mph.Unfortunately for her figures , in their ‘youth’ starting with cute square eight wheel tenders , that sort of exploits made most members of the class a case for the 'weight watchers anonymous' acquiring heavy ‘low rider’ 12 wheelers and even 16 wheelers , a rare case of tender with more wheels than engine – in my view an indication of consumptions having scored way out of reasonable proportion . However , all Pennsy cared for was if they got their trains over the line or not - to do it even let'em have two twelve wheel tenders if that’s what gets the job done . The earlier R1 class 4-8-4 type would not have offered much of anything to improve that situation in freight train traffic : same limitation of adhesion and tractive effort , same inefficient use of steam working on long cut off for miles on end , engine screaming her heart out on maximum tonnage - only , a more powerful boiler and larger grate would probably have 'allowed' for carrying an already extreme situation a bit further into extremes . All in all nothing really inspiring as for train traction with steam facing the diesel challenge . The earlier R1 would have presented a keystone class to complete the family of PRR standard steam loco classes - however it proved there was no real demand for it . The later R2 would have provided awesome looking engines in the style of Pennsy's Duplex Q-2 , yet that latter engine class for sure was clearly more awesome again . So , in the end the PRR 4-8-4 although technically well possible had to remain a class filling a gap not felt in actual traffic handling . Remained one possible application for R2 engines , unforeseen at the time : replacement of T1 engines on heavy passenger trains leaving the T1 squeezed into redundancy between the R2 and K4 classes even more than they were in between K4 and early diesels ... Or : one more steam class built would have kicked one steam class just built out of service – seems there really was no perspective for steam on the Pennsy after 1945 .Regards= J =
Edit : intro sentence added to be sure not to be misunderstood about the article and drawings
Well, actually there ARE some Pennsy 4-8-4's out there, quite a few as a matter of fact. Unfortunately they're variations on a Class "J" in "O" gauge made by Williams. Quite handsome as a matter of fact, sleek, pinstriped and very impressive. Ah, what might have been.
Hi Firelock
Oh - I see ...
Yet another point where modelrailroading shows the way to sleepy-drowsy RealRoads ..
.. if but some few years after the end of the Carbonian Age .
Yet , I ask : what about a that missing link of a Duplex 4-6-6-4 or 6-6-6-6 , preferably ?
the kind of locomotive cutie more optimistic people like me have since been waiting for ?
Just one of these innocently simple questions so hard to answer , I believe .
Regards
Juniatha
Juniatha Hi Firelock Oh - I see ... Yet another point where modelrailroading shows the way to sleepy-drowsy RealRoads .. .. if but some few years after the end of the Carbonian Age . Yet , I ask : what about a that missing link of a Duplex 4-6-6-4 or 6-6-6-6 , preferably ? the kind of locomotive cutie more optimistic people like me have since been waiting for ? Just one of these innocently simple questions so hard to answer , I believe . Regards Juniatha
A Duplex 4-6-6-4 or 6-6-6-6? Hmmmm, maybe Mike Wolf (Mikes Train House) or Jerry Calabrese (Lionel) are looking in on this and who knows what might happen. Actually, Lionel had a real wierdy out a few years ago called the "Phantom" locomotive, looked like a cross between that whacked -out turbine locomotive that the C&O had and a vacuum cleaner ( a floor model). I think Neil Young had something to do with it, you know how rockers are.
Phantom loco?? There's a picture of one at the 10 O'clock position on the Lionel clock on my (home) office wall... Kind of a weird sound effect too.
- Erik
quote :
>> like a cross between that whacked -out turbine locomotive that the C&O had and a vacuum cleaner ( a floor model) ... <<
... and I had always thought the Chessi 500 was a vacuum cleaner ( luxury XXL rail model ) modelfiddled to indiscriminatingly suck up , finely grind and hastily expel just about anything from pieces of superfluous ballast , diverse coals and cinders , loose track fixing items to whole sedans parked at the Walmart parking lot alongside the CSX main leaving the freight yard .
CSX ? Well , from sources occasionally strangely prejudiced I heard the 500 - 502 had escaped steam scrapping because everyone who happened to see them in real (or unreal ?) immediately developed unsurmountable doubts if this could be steam locomotives at all . On the other hand there was a wide spread problem with people having no idea what if any was the deeper transport-philosophical meaning of this accumulation of powered and non-powered axles under one long hood . Some of the more outlandish guestimates meandered around an exxon-terestial monster escaped from Area 51 or a sperm whale redesigned from deep sea diving to high mounting climbing - which would have been hard to believe since this was five decades before gen tech experimenting even started .
In the end , it must be conceded , the locomonsturbous have since quietly disappeared - again by circumstances shrouded in mystery . Some still maintain they have just gotten weary of leading a shelved life , became deeply depressed and just sunk away in the embankment ..
Yet again : exactly where was that ? where should we start searching with dowsing rods for a possible excavation project ?
No one knows .. or ?
wondering ,
erikem Phantom loco?? There's a picture of one at the 10 O'clock position on the Lionel clock on my (home) office wall... Kind of a weird sound effect too. - Erik
That's the one, Brother!
Now why didn't I think of this sooner? How about a 6-6-6? We could call it a "Lucifer" type!
I have a drawing of a 6-6-6 type - it's a design of my own .
I gave it a very different name from mythology , though .
Hi Juniatha! Oh, now I'm curious, what do you call your 6-6-6 type? Anything with that "mark of the Beast" arraingement exhausts my knowledge of names for the "Dark One." "Beelzebub", Mephisto", "Old Scratch", "Rosemary's Baby's Dad"....
The name was none of these rather negative ones . It was derived from white magic as the locomotive type was supposed to do something positive . I will tell you in a message , presently I don't feel like posting any locomotive proposals or the like .
Hi Juniatha! Dear lady, I could have used some "White Magic" on the job today. I'm so tired right now I can barely see straight. Took me three attempts to spell "tired" correctly.
Juniatha I have a drawing of a 6-6-6 type - it's a design of my own .
Lima apparently had drawings for a 4-8-6, with the large firebox made possible by the six wheel trailing truck intended to allow slower combustion of coal for better fuel efficiency. I would imagine there would be considerably more direct (radiant) heating surface in said firebox.
Hi Erik
More direct heating surface – mmmiouh – yeah-well , ok . But that didn’t provide the main difference . One point was increasing grate surface , sure . However what Lima had put up as their burnt offering in the face of dieselization was a double Belpaire combustion chamber , as the Belpaire when doubled i e also used for the lower part meant to offer a slightly larger cross section for free gas area . So , did it ? Well , yes and no ! It did for a given boiler drum diameter – it didn’t for a given construction mass of a boiler at firebox end ( inevitably it incorporated a somewhat greater mass accumulation , thus for a given engine project it would have meant to slightly reduce boiler drum diameter and firebox / combustion chamber cross section – thus nullifying the effect , the same mental short circuit as in the Belpaire to start with ) .
The 4-8-6 all in all was an effort to repeat an idea that had worked well some twenty years earlier : ‘Super Power’ – first appearing as 2-8-4 to replace 2-8-2 . It had worked just great then because the competing engines were of principally same t.e. yet the new Lima large firebox power had more stamina at speed . The same idea had to fail when put up against a competitor offering unparalleled qualities in low speed heavy pulling and on top of that offering a completely novel feature with multi unit traction allowing to part or assemble power to train loads – as opposed to tailoring train loads to engine tractive effort as with steam power . The RRs went just mad about that feature , piling up units or locomotives on huge train loads is something they still consider gorgeous in America , if a freight train is not at least half the length across a decent state it’s not considered worth mentioning – or so it seems , *g* .
In that light , the Lima proposal had to fail since basically it aimed at improving steam in something that was already more than amply realized in a good dual purpose 4-8-4 : generous steam production , already more than enough at freight train speeds !
Although it came to me as a straight forward enlargement on a Hudson , much the way the 6-8-6 enlarged on the Northern , the 6-6-6 called for some individual design changes as compared with a 4-6-4 , namely cylinders were re-positioned behind the front truck , consequently having shorter main rods , consequently using shorter stoke – consequently going for a three cylinder layout .
Upon having seen the deGlehn four cylinder compound engines in the railway museum of Mulhouse with their aristocratic compact hp cylinders and light rod systems I went for a similar deGlehn layout , well supported by that w/a since as mentioned the outside cylinders had to be repositioned immediately front of first driving axle , leaving lots of space to forward position inside cylinders and provide for receiver chambers , installing a wide lateral connection as an extra receiver volume without too much visible size of it which I considered compromising aesthetic looks – by the way something I only later learned L.D. Porta had strongly recommended to do in order to level out steam pressure fluctuations caused by valve port operations . To balance for a formidable firebox behind very large driving wheels I designed large ‘elephant ears’ type of smoke wings , using remaining space in front of outside cylinders for mounting feed and air pumps left and right sides below the smoke box , with the lower part of the wings covering air reservoir just snuggly fitting in below straight running board which continued behind wings to the front of the locomotive .. where young June got somewhat devoid of a flashing idea about how to deal with front end looks . First impulse to put a slanted front plate between wind wings as British , French and German railways often liked to do was not satisfying . I rather wanted something slender and ‘open’ like in some DB 01 Pacifics ( however having small Witte wings ) .
Finally I settled with a straight cut end of running boards and a ‘sloping nose’ middle section below smoke box front as in DB 01.10 Pacifics without side valances sections to let air stream pass through and outwards .
Another challenge was to fit a tender which would neither belittle the dominant theme of large firebox , nor look too delicate for this large an engine , bespeak speed without losing too much capacity . It turned out a double six wheel bogie tender .
It was quite intriguing to do calculations on possible outputs over speed range – ok , to cut it short , calculations indicated performance characteristics would approach that of a Bo-Bo electric i e indicated cylinder power output vigorously rising with speed , traction bar effort would only fall away to a much smaller extend with speed rising than it did in a Pacific of comparable adhesion mass . To some degree this was little surprising with that much larger a steam capacity acting on cylinders offering just lightly higher t.e. at starting , combined by an ample steam circuit . With the special cylinder spacing provided by this w/a there was space enough to accommodate an unhampered layout of steam circuit . Draughting was rather conventional with a double Kylchap helped by low , level position of inside cylinders driving to first coupled axle . External looks were much to lines of American Super Power although with a straight level boiler top line and with engine and tender being generally leaner as for demands by European axle load limits of 22 t [metr] .
With this many carrying axles , it was seducing either to fit a booster – yet I never liked the idea – or to provide for some adhesion mass augmentation. I contrived a fail-safe auxiliary suspension for it which could easily load powered axles to some 25 t [metr] or – unofficially ? – much better at starting . I guess , after so long a period of full use during start and extended acceleration by some exceedingly ambitious drivers the device might later or sooner have been banned due to some strong inputs from track maintenance dept . As long as working , though , it would have allowed for making some positively energetic get-aways .
Well, to get back to the original question, We'll never really know if the PRR's Mountains would have been the equal of the speculative R2 class but there is some basis for informed quesswork provided by the Southern Pacific. SP had extensive experience with its MT class 4-8-2's and it also had a big stable of GS class 4-8-4's. The ultimate Mt's had 73" drivers and a rated tractive effort of 57,510 lbs. The passenger versions of the GS classes had 80" drivers and a TE of 78,650 lbs. SP engineers often stated that an MT ( they nicknamed them Antelopes ) could actually start a heavy train more easily than a GS type on account of having one less truck axle and that there was no hesitation about using an MT as protection power for trains normally assigned a GS. Both types could be found working fast freights and fruit blocks pretty much interchangeably. Perhaps this supports the argument that the PRR really didn't need to develop a conventional 4-8-4 as long as it had its large stable of M class locos? Still. SP got a lot of use out of its examples of the two types.
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