History of the E-unit

Discussion of Electro-Motive locomotive products and technology, past and present. Official web site can be found here: http://www.emdiesels.com/.

Moderator: GOLDEN-ARM

Re: History of the E-unit

Postby Pneudyne » Sat Jul 25, 2015 9:30 pm

mtuandrew wrote:I don't see that EMD offered a turbocharged 8-567, but was there ever any interest by railroads in acquiring or rebuilding E-units to 2 x turbo 8 configuration for lighter weight? (or for that matter, keeping the A1A trucks and moving to 1 turbo 16-567)


As far as I know, the first turbocharged “8” was the 8-645E used in the GT18 export model. The first production of that seems to have been the GT18MC for South Africa, supplied from 1974. Whilst the GT18 did have wider sales, it should not surprise me too much if in part EMD developed the GT18 in order to match the GE U15C, which South Africa also bought in parallel. I doubt that the GL22C could have been pared down enough weightwise to match the South African version of the U15C, so the “turbo-8” was required. If it happened that way, then it was déjà vu for EMD. It broke into the hitherto GE-dominated South African market in 1966 with the GL26MC. And it apparently got there by making its G26 smaller and lighter than the preceding G16 to the point where it was more-or-less a ringer for the GE U20C, by then very popular in sub-Saharan Africa.

I did once hear anecdotally that the South African GT18MC fleet was not entirely comfortable in its branch line and secondary service role, involving as it did frequent throttle changes, which the turbocharger overrunning clutch did not much like.

Back to the twin 8-567CR idea, that configuration was actually used in the Henschel KK16 locomotive, a double-ended cab unit built for Egyptian Railways in 1957, an EMD licensed design. So the basic engineering work had been done, and one imagines, had been signed-off by EMD.

In fact all of the cylinder count variants, six through sixteen, of the 567 engine were used in twin-engined locomotive installations. A 6-567 pair installation was used by Henschel in the seven B-B centre-cab diesel-hydraulic locomotives it built for South African Railways in 1958.

I suspect though that a twin 8-567 installation would have been exceptionally noisy, and not a good choice for passenger service. New Zealand Railways had a fleet of the somewhat modified G8 model, in-service from 1965. Singly, in suburban passenger service they seemed to be noisier than the G12s. If the train stopped on a downgrade with couplers compressed, the engine vibration was transmitted back to the leading car. And the transition “bump” was very noticeable. In pairs in freight service, when running at notch 8 upgrade, they would develop a low frequency beat note that as well as being very loud, on a still night would rattle windows and doors in houses several hundred yards away. Maybe aviation-type synchronizing devices would have helped. (I’d say that a pair of 8-567CRs were more obnoxious, noise-wise than four Wright Turbo-Compounds on a DC-7C.) Whether the multiple 8-645s would be any quieter than multiple 8-567s I don’t know.

Cheers,
Pneudyne
 
Posts: 308
Joined: Fri Mar 16, 2012 6:13 pm
Location: Mt. Maunganui, New Zealand

Re: History of the E-unit

Postby Allen Hazen » Sun Jul 26, 2015 1:24 am

Weights are hard to estimate. Looking at various sources, I have found wildly different figures for locomotives of the same model: to what degree this is because of different equipment options, different conventions(*), or sheer inaccuracy I don't know.

For twin-engined passenger units of E-like configurations (so: A1A trucks, truss carbody)…
Alco's Dl-109 seems to have ranged between 330,000 and 360,000 pounds. (Round numbers.) The only figure I've found for the Baldwin version is 387,000 for the PRR's A units. (The PRR's units were equipped with two turbocharged six-cylinder engines in place of the two normally aspirated eight-cylinder engines used on earlier Baldwin passenger units, which in principle should have allowed some weight reduction. But I don't think the PRR was terribly concerned with weight reduction in its first generation diesels!)

E-units got heavier as the design evolved. The very first E-units (1800 hp, from two 12-201 engines) may have been a bit under 300,000; a figure I've seen for the E-8 is 315,000.

So: how much would a 3000 hp derivative of the E design in the late 1940s have weighed? For a first estimate, let's assume each 16-567 is 10,000 pounds heavier than a 12-567. (This is probably high, but I'm only trying for a ballpark figure.) Add two traction motors, at 6,000 pounds each. The carbody is probably a bit longer than that of a real-world E (longer prime movers fitted into it, more radiator spaced along the roof…), and has to carry the weight of the heavier engines, so there would have to be some additional "structure" weight, and I have NO IDEA WHATEVER what this would be. Still, all up I think EMD could have done it with a unit weighting not much over 360,000 pounds. This is much lighter than a DD-35, but I think this can be accounted for by the fact that a truss carbody construction like that of an E allows a locomotive to be much lighter than a roadswitcher configuration in which a fairly shallow frame is the only structural support.

---

(*) At least in the U.S. the convention for giving weights of steam locomotives was to count the weight with the tender two-thirds full of fuel and oil. I ***THINK*** that diesel weights are given with full fuel tanks: even with the comparatively small tanks of first-generation diesels, the difference between this and a two-thirds-full figure would be several thousand pounds.
Allen Hazen
 
Posts: 2340
Joined: Fri Mar 12, 2004 10:14 pm
Location: Edmonton, Canada (formerly Melbourne, Australia)

Re: History of the E-unit

Postby Pneudyne » Tue Jul 28, 2015 3:32 am

Agreed that weights are difficult to estimate. Even if one could get within about ±5%, which seems not too likely, that would still be around a 360 000 to 400 000 lb range on my 380 000 lb number.

315 000 lb is the weight I have seen quoted for both the E8 and E9.

EMD numbers for the F9 and GP9 were:

F9: 226 000 to 248 000 lb

GP9: 240 000 to 248 000 lb.

The base weight difference implies 14 000 lb inherent advantage for the F9 carbody structure over the GP9, a bit under 6%.

Whether the F9 range encompasses the FP9 I do not know, but I have seen 260 000 lb quoted as the upper limit for the FP7 and FP9 variants.

A Railway Gazette 1963 November 08 article quoted the following weights for the GP35 and DD35:

GP35: 108 long tons, roundly 242 000 lb.

DD35: 217.85 long tons, 232.1 long tons with ballast, or 488 000 and 520 000 lb respectively.

The DD35 was certainly quite heavy relative to the GP35, which in turn was not materially different to the GP9. There was no economy-of-scale, so as to speak; rather there was a diseconomy. But then for its mission, it would have needed to weigh at least as much as a pair of GP35, and evidently UP wanted more than that.

The Egyptian KK16 was also quite heavy, at 132 long tons, roundly 296 000 lb. So it was getting close to an E9 in weight terms.

Cheers,

EMD F9 p.02.gif

EMD GP9 p.02.gif


DRT 195707 p.243 Egypt KK16.gif
Pneudyne
 
Posts: 308
Joined: Fri Mar 16, 2012 6:13 pm
Location: Mt. Maunganui, New Zealand

Re: History of the E-unit

Postby Allen Hazen » Tue Jul 28, 2015 10:12 pm

Pneudyne--
Thank you AGAIN for posting items from your archive!
The KK-16 is a truly weird beast: I can't help feeling that someone, either at Henschel or (more likely, perhaps) Egyptian Railways, didn't really understand what they were doing! … The double-ended carbody isn't so strange to someone who used to live in Melbourne (for those who don't already know, Victorian Railways in Australia had a class of double-ended, CC, F-unit derivatives: their B class, AA7 (I think) in EMD-speak, some rebuilt in the late 1980s (early 1990s?) with turbocharged 12-645 engines instead of their original 16-567)-- though it looks as if the ends of the underframes have been heavily modified from the F-unit design to accommodate the buffers. But the choice of "working parts"!

I can't help thinking the overall maintenance costs of having two engines instead of one would have eaten up any savings gained by having all 8-567 instead of a mix of 8-567 and 16-567in the fleet. And use of A1A trucks on a unit intended for heavy freight service… in 1957! After all, EMD had been providing C trucks, both for domestic (SD-7, SD-9) and export (Vic Rail B-class, among, I think, many others) for several years at that time. I suppose the Egyptians wanted to keep the initial purchase price down, and knew that American railroads used 4-motor F-units on freight…

---

Re: weights. I think 242,000 pounds for a GP-35 would be the weight for a "stripped-down" (no dynamic brakes or other options, probably the smallest fuel tank on offer) version, and that the majority of units actually built would have been closer to 260,000. (One source I could find-- Alvin Stauffer's "Pennsy Power II"-- says that the Pennsylvania Railroad's GP-35 were over 261,000 pounds.) Note that the DD-35 was originally built as a B-unit, and EMD's proposed application was in 4-unit, 15,000 hp, sets (the launch customer, Union Pacific, having apparently said it wanted 15,000 hp locomotives for its freights): GP-35, DD-35, DD-35, GP-35. If Union Pacific ballasted its DD-35 520,000 pounds, it would probably have wanted the GP-35 leading one to have the same weight per axle, so 260,000.
Allen Hazen
 
Posts: 2340
Joined: Fri Mar 12, 2004 10:14 pm
Location: Edmonton, Canada (formerly Melbourne, Australia)

Re: History of the E-unit

Postby Allen Hazen » Tue Jul 28, 2015 10:21 pm

Re: Buffer beams. Vic Rail didn't use buffers on its F-derived units (B class, and single cab S class), but New South Wales Railways did on its 4200 class (another CC F-unit derivative). The 4200, however, does not seem to have the prominent frame-end modifications that the Egyptian KK-16 has. Different design judgments at Henschel and Clyde(*)? Or perhaps, since the 4200 had an American-style coupler between the buffers, the buffers didn't have to withstand as large a proportion of the stress of "buffing" as the buffers on the Egyptian units (which I am assuming had British-style hook and link couplers) did.
--
(*) Clyde Engineering was EMD's Australian licensee, the builders of the Victorian and NSW units. Engines and electricals were imported from the US, but the "locomotive mechanical portions" were largely Australian-made (though I think metal stampings for the complexly curved F-unit cab and nose were imported).
Allen Hazen
 
Posts: 2340
Joined: Fri Mar 12, 2004 10:14 pm
Location: Edmonton, Canada (formerly Melbourne, Australia)

Re: History of the E-unit

Postby Pneudyne » Wed Jul 29, 2015 6:04 pm

Allen Hazen wrote:And use of A1A trucks on a unit intended for heavy freight service… in 1957! After all, EMD had been providing C trucks, both for domestic (SD-7, SD-9) and export (Vic Rail B-class, among, I think, many others) for several years at that time. I suppose the Egyptians wanted to keep the initial purchase price down, and knew that American railroads used 4-motor F-units on freight….


The use of four motor might have been something of a forced choice. Each power unit was independent, with 2S and 2P traction motor groupings. Having six motors and retaining that independence would have dictated a permanent 3P arrangement, and that in turn would have required a noticeably larger capacity generator than was normally associated with the 8-567 engine. As far as I know the standard six-motor units, SD7 and SD9, started with the 3S2P grouping, so even the main generator used therein might not have been too happy with a 3P start, at least with the SB gauge motors.

Alternatively it would have been possible to connect the two main generators in series and then have the usual six-motor sequence, 3S2P, 2S3P and 6P, or some part thereof, but although series connection of main generators was done here and there, typically it did involve higher maximum voltages. I am not sure how the EMD SB gauge motors of the time would have handled this, but the contemporary D19 CM gauge motors did not much like higher voltages, particularly in weak field, and were reputedly quite prone to flashover.

Cheers,
Pneudyne
 
Posts: 308
Joined: Fri Mar 16, 2012 6:13 pm
Location: Mt. Maunganui, New Zealand

Re: History of the E-unit

Postby Pneudyne » Wed Jul 29, 2015 6:23 pm

Allen Hazen wrote:Re: Buffer beams. Vic Rail didn't use buffers on its F-derived units (B class, and single cab S class), but New South Wales Railways did on its 4200 class (another CC F-unit derivative). The 4200, however, does not seem to have the prominent frame-end modifications that the Egyptian KK-16 has. Different design judgments at Henschel and Clyde(*)? Or perhaps, since the 4200 had an American-style coupler between the buffers, the buffers didn't have to withstand as large a proportion of the stress of "buffing" as the buffers on the Egyptian units (which I am assuming had British-style hook and link couplers) did.


The NSWGR 42 class originally had buffers and screw couplings, and was retrofitted with automatic couplers. Possibly the difference is that in the KK16, the frame ends were dropped, and so required relatively heavy construction to handle the buff and drag loads through the “goosenecks” without distortion. In the NSWGR 42, I think that the main frames extended to the locomotive ends without being dropped, and that drag boxes were fitted (welded, I imagine) underneath, with the couplers and buffers mounted on these.

Cheers,
Pneudyne
 
Posts: 308
Joined: Fri Mar 16, 2012 6:13 pm
Location: Mt. Maunganui, New Zealand

Re: History of the E-unit

Postby Pneudyne » Thu Jul 30, 2015 1:19 am

Attachments to illustrate my previous post.

Cheers,

DRT 195707 p.244 Egypt KK16.gif


DRT 195804 p.131.jpg

DRT 195804 p.132.gif
Pneudyne
 
Posts: 308
Joined: Fri Mar 16, 2012 6:13 pm
Location: Mt. Maunganui, New Zealand

Re: History of the E-unit

Postby Pneudyne » Sat Aug 01, 2015 12:40 am

Allen Hazen wrote: The KK-16 is a truly weird beast: I can't help feeling that someone, either at Henschel or (more likely, perhaps) Egyptian Railways, didn't really understand what they were doing.


Yes, more likely Egyptian Railways. Henschel would have had little reason to propose a non-standard design, although clearly prepared to build such if the customer insisted. Another somewhat customized design of the period was the TT12 “verandah” style double-ended cab unit, C-C, built for Ghana in 1959.

Whatever the justification for the KK16 fleet, it seemed not to be sustained as Egyptian Railways did revert to more normal designs, following the KK16 with both the AA16 and AA12 types. The AA16, with a single 16-567C engine, was still A1A-A1A, though. The AA12 were B-B.

Cheers,

DRT 196107 p.286.jpg
Pneudyne
 
Posts: 308
Joined: Fri Mar 16, 2012 6:13 pm
Location: Mt. Maunganui, New Zealand

Re: History of the E-unit

Postby Allen Hazen » Sat Aug 01, 2015 4:59 pm

Pneudyne--
The treasures (and yur commentary!) keep coming! Many, many thanks.
Remarks:
1. I had forgotten, if I ever knew, that the NSWGR 42 class was delivered with British-style couplers. So much for my speculation that the reason they didn't have "gooseneck" frame ends to support the buffer beam was that the draft gear of the American-style (Janney) couplers reduced the stress on the buffers.
2. The AA12 looks similar, in carbody styling, to the units built by one or another European EMD licensee for a number of European railroads (Danish, Norwegian, and I think Hungarian among them). Design may have been collaborative, but this seems to have been close to an EMD standard offering for railways that wanted something like an F-unit but couldn't (for axle loading or clearance reasons) accommodate the domestic models.
3. The drawing of the big Egyptian A1A-A1A (from a 1957 issue of "Diesel Railway Traction," so well before the actual building of the locomotives) shows an 8-cylinder engine, but the article on the AA12 you just posted (from a 1962 issue) says the bigger units had 16-cylinder engines. Do you know otherwise that they were actually built with twin 8-567, or is it possible that sanity crept in between the initial order and actual construction? (Another possibility, of course, is that the later article is just in error on this point. Given the amount of sanity in the world….)
Allen Hazen
 
Posts: 2340
Joined: Fri Mar 12, 2004 10:14 pm
Location: Edmonton, Canada (formerly Melbourne, Australia)

Re: History of the E-unit

Postby Pneudyne » Sat Aug 01, 2015 8:57 pm

Allen Hazen wrote:2. The AA12 looks similar, in carbody styling, to the units built by one or another European EMD licensee for a number of European railroads (Danish, Norwegian, and I think Hungarian among them). Design may have been collaborative, but this seems to have been close to an EMD standard offering for railways that wanted something like an F-unit but couldn't (for axle loading or clearance reasons) accommodate the domestic models.



As far as I can tell, the AA12 was simply a smaller version of the AA16, which as you say, was something of a European standard, built by EMD licences Nohab, Anglo-Franco-Belge (AFB) and Henschel. There were both A1A-A1A and C-C variants. I suspect that some of the F7 re-engineering that went into the AA16 design was common to what was done for the Clyde-GM “A” series in Australia, wherefrom possibly came the model letter. I have attached equipment layout diagrams for both the Danish State Railways (A1A-A1A) and SNCB Belgium (C-C) variants of the AA16.

DRT 195406 p.126 DSR Nohab-EMD AA16.gif

DRT 195505 p.156 SNCB AFB-EMD AA16.gif


Allen Hazen wrote:3. The drawing of the big Egyptian A1A-A1A (from a 1957 issue of "Diesel Railway Traction," so well before the actual building of the locomotives) shows an 8-cylinder engine, but the article on the AA12 you just posted (from a 1962 issue) says the bigger units had 16-cylinder engines. Do you know otherwise that they were actually built with twin 8-567, or is it possible that sanity crept in between the initial order and actual construction? (Another possibility, of course, is that the later article is just in error on this point. Given the amount of sanity in the world….)


The Egyptian sequence of early Henschel-EMD cab units appears to have been KK16, AA16 then AA12. The order for the AA16 (1 x 16-567C) rather than a repeat of the KK16 (2 x 8-567C) certainly suggests an ingress of sanity, but on the other hand, the differences in weights, 132 long tons for the KK16 as compared with 108 tons for the AA16 indicates that they might have been acquired for different duties or use on different parts of the network.

What the "K" in KK16 designates I don't know, but "klein" seems unlikely...

Cheers,
Pneudyne
 
Posts: 308
Joined: Fri Mar 16, 2012 6:13 pm
Location: Mt. Maunganui, New Zealand

Re: History of the E-unit

Postby Allen Hazen » Mon Aug 03, 2015 9:30 pm

I think EMD -- either when the units were built or retrospectively -- used "A" as a prefix for model numbers for a variety of streamlined units that didn't fit into the regular F or E series (including a couple of single engined, A1A-3, variants of the E unit design with a baggage compartment where the second engine should have been. When used for export units, the same model designation could be applied to radically different designs. (Example: Victorian Railways N class and CIE (Irish Railways) 71 class were both described by EMD as "JT22C", but have very little in common except for both being twin-cab units with turbocharged 12-645 engines.) Doubling the "A" to denote a twin cab unit is a fairly obvious move, though twin-cab export hoods are "J" models rather than "GG". (I doubt that anyone in the U.S. railroad or railroad supply industries would have DARED use "GG": the Pennsylvania Railroad's big electric was TOO famous! (Grin!))

"KK" is a mystery to me. I don't think I had ever seen "K" in an EMD model number before you told us of this remarkable Egyptian unit!
Allen Hazen
 
Posts: 2340
Joined: Fri Mar 12, 2004 10:14 pm
Location: Edmonton, Canada (formerly Melbourne, Australia)

Re: History of the E-unit

Postby Pneudyne » Tue Aug 04, 2015 10:52 pm

Thanks Allen.

Yes, some of the EMD designations have no obvious origin. Another example is the “TT12” used for the late 1950s Ghana 12-cylinder units. They were double-cabbed, hence double “T”, but why “T” is a mystery. Well, maybe it was T-for-tropical. The verandah-style construction allowed easy but covered access to the engine, generator, etc., and from the outside, thus overcoming a problem with cab units that any internal work required during layover right after a run needed to be done in what could be impossibly hot conditions when in the tropics.

Perhaps the “B” for the B12 cab unit was chosen simply because B followed A, and A was considered as reserved for standard gauge cab unit designs.

“G” as in G12 I have long assumed referred to its general-purpose nature, and was perhaps chosen to avoid any conflict or confusion with the domestic GP-series.

Then there is “R” as in the never-built export model. The “R” turns up again in the GR12, and I have heard that therein it meant “road”. As in one might use a G12 for all kinds of service, but a GR12 would more likely be used primarily for road service. It is not convincing though. Clyde-GM built the first GR12s, for Queensland Railways in 1957. But although that was the official designation, and the one shown on the Operating Manual cover, right away Clyde also referred to it as the “G12C”. Alignment between Clyde and EMD models with the same designation was never perfect, and they seem to have drifted further apart over time. There also appears to have been some retroactive redesignation of Clyde models, although whether that was officially done by Clyde or unofficially by outside observers is unknown.

Cheers,

GM DE Locos p.07.jpg

GM DE Locos p.11.jpg

GM DE Locos p.15.jpg
Pneudyne
 
Posts: 308
Joined: Fri Mar 16, 2012 6:13 pm
Location: Mt. Maunganui, New Zealand

Re: History of the E-unit

Postby NorthWest » Sat Aug 08, 2015 11:30 pm

Interesting R and B models. I have a thread on another forum that collects diesel locomotive models that were catalogued but not built. I may have to add to that, or start a new one here and combine them. I'd appreciate any help that you could give me in finding more.

I've always thought that GR12s were built for heavier duty freight service with detail differences from standard G12s. I haven't figured out exactly what these differences are, though, as I haven't really thought of this until now. Perhaps it is extra weight, different gearing, or ...?

My understanding is that from construction the QR locomotives were classified as G12Cs, (perhaps to help differentiate from the earlier QR A1A G12s) as they had to deal with difficult (some say ridiculous) QR weight and loading gauge requirements.
User avatar
NorthWest
 
Posts: 387
Joined: Tue Jul 15, 2014 1:54 pm

Re: History of the E-unit

Postby Pneudyne » Sun Aug 09, 2015 3:25 am

I’ll plan on posting the other catalogue pages pertinent to the EMD R. That is the sole total of information that I have on it.

The B12 was built for two customers, in B-B form for RFFSA Brasil, and in A1A-A1A for East Pakistan (Bangladesh).

The only other distinct EMD export model that I am aware of that was catalogued but not built was the G6 (not the same as the later Clyde-GM G6B), which basically had the 6-567C engine in the same frame as used for the G12 and G8. I have not actually seen any documentation, but I recall some being offered on eBay quite some years back.

The GE export Universal line included some never-built models, but I guess that these would be better discussed in the GE forum.

Re the EMD GR12, this was essentially the C-C derivative of the G12. It was offered by EMD from at least as early as late 1958, although I think not built until circa 1961. The GR12 was included in the model list shown in EMD’s epic six-page advertisement in “Diesel Railway Traction” for 1958 November, which I think has had quite wide circulation. The full list of models included therein was: GM6, GA8, GL8 (B-B only at that time), G8 (B-B and A1A-A1A variants), G12 (B-B and A1A-A1A variants), GR12, G16 (presumed B-B, A1A-A1A and C-C variants), GMDH-1 and GMDH-3.

As far as I know the G16 was built only in C-C form, so I guess that the putative B-B and A1A-A1A variants fall into the “catalogued but not built” category, if this extends to variants of otherwise built designs.

The Clyde-GM GR12 thus preceded the EMD GR12, and as I understand it was built at QR’s request. QR had started its main line diesel fleet in 1952-53 with a pair of 90 (long) ton C-C designs, one from GE and one from English Electric. This “90-ton” form became QR’s standard for around three decades, naturally with progressive improvements and higher power outputs. Clyde-GM was the majority supplier of the type. Against that, the Clyde-GM G12 in A1A-A1A form and 60 long tons adhesive weight was found – not surprisingly - to be somewhat slippery when it was applied to the same duties as the 90-ton C-C models. Hence the rethink on Clyde-GM’s part.

The QR’s GR12 fleet, its “1450” class, as expected, weighed in at 90 tons, but Clyde-GM advertising indicated a base weight of 84 (long) tons. That was academic as none were built other than those for QR. The Clyde-GM GR12 was somewhat longer than the following EMD GR12. This difference followed a precedent established with the Clyde-GM versions of the G8 and G12. These were 18 inches longer than the EMD parent model, both overall and in respect of the truck centres. I understand that this was to accommodate a larger fuel tank. The body was the same length as on the prototype, the extra frame length accommodating a “back porch”. GMD then used the back porch on the modified G8 for New Zealand Railways of 1965. This had the standard 43 ft frame length, but the engine was moved forwards and downwards to allow a lower overall height.

As to designation, as mentioned previously, GR12 was used in the operating manual for the QR1450 class. It also seems to have been used in QR internal documentation; QR claimed that it had the first GR12 built. GR12 is also the designation shown in the EMD catalogue “Product Reference Data, Export Locomotive 1986”. On the other hand, an article on the QR 1450 class in “Railway Transportation” magazine for 1958 July referred to the Clyde-GM G12C model, as did a Clyde-GM advertisement in the same magazine. One suspects that perhaps Clyde-GM preferred G12C, but that EMD was not yet ready to use the C suffix. In general, it did not use the C suffix for export models until the advent of the 645-series engine, as for example in the “G22C”. There was a possible prior exception, though, in the form of the GA12C built for India. That was the designation used in an article in “Railway Gazette” for 1965 March 19 for the C-C model, in contradistinction to GA12 as applied to the 1-B-B-1 model. But then the above-mentioned 1986 EMD list shows both groups as simply GA12.

Be that as it may, Clyde-GM had its way with its next iteration on the GR12 theme, which was properly known as the G12C, first built for Western Australian Government Railways in 1960 as its “A” class, and for QR in 1964 as its “1460” class. The 1968 EMD lists shows both as G12C, as does the QR 1460 class operating manual and the QR documentation that I have seen.

Cheers,

QR 1450.jpg

QR 1460.jpg
Pneudyne
 
Posts: 308
Joined: Fri Mar 16, 2012 6:13 pm
Location: Mt. Maunganui, New Zealand

PreviousNext

Return to EMD - Electro-Motive

Who is online

Users browsing this forum: No registered users and 2 guests