GATX fleet breakdown?
Steve and Barb Hile
Let me add a bit more to what Dave is saying. Attached is an Excel file of data gleaned from GATX 18981948 A History of the General American Transportation Corporation by Ralph C. Epstein. There is data buried in the text and summarized in Appendix tables. Hopefully this will make some sense.
Some things to note include that GAT built lots of cars for other lines, besides their own fleet. The owned fleet expands rapidly in the period between 19251935 with the acquisition and management of other lines. Very few new cars are built in the early 1930’s, but cars were being repaired and refurbished.
Steve Hile
From: main@RealSTMFC.groups.io [mailto:main@RealSTMFC.groups.io] On Behalf Of Dave Parker via groups.io
Well, I do have some numbers that may or may not shed any light on the question of the abundance of GA 1917 design cars. 

Tangent Scale Models
Guys,
Thanks to Dave Parker for sharing his research from Railway Age tabulations and subsequent analysis on the likely GATC production numbers for the first years of General American production, including the subject cars here, the 1917Design tanks. (Bruce, the German American name was dropped in 1916).
I too have done my own research on this, and built my own business case for spending lots of money tooling the 1917tanks. Spoiler alert for Bruce Smith (and Tony Thompson who seemed to resoundingly agree): they are not “minority cars.” If you will indulge a “dumb manufacturer” (but one who does his homework) to weigh in, please read on.
First let’s look at the numbers. Here is the raw data of GATC tank car builds, by production year, compiled from Dave Parker’s 19171921 data and the stated production numbers in Epstein’s “A History of General American Transportation Corporation.” Also included is a key element, which is the body type.
Now when those numbers are aggregated, you can see the breakdowns by body type:
So you might say, you see! The 1917design is only 25%  there are more numerous GATC builds! Yes, that is true from a raw numbers standpoint, but let’s peel that onion a bit more, and look at how many carbodies were built by GATC for each frame design:
So is the 1917Design a “minority car?” A few comments:
But what about the “Type 30s!” Conversely, the 1928Design cars (dubbed “Type 30”) were produced in larger numbers at 43%, or 15,570 cars at least, possibly a few more in 1945 and 1928. But consider this. By 1928, based on market demand for specialized service tank cars, GATC had introduced many tank car size and type options. As the table above states, I count at least 30 different body types sitting on 1928design underframes (of varying lengths just to add to the complexity). Yes, the 8,000 and 10,000 noninsulated cars were significant cars, but there were many other significant cars as well, and in multiple body configurations:
This is the closest analysis we will get to figuring out whether the 1917design tank is a minority car. I think it is very clear it is not, since 2 car types dominated the total production of 9,079 cars. The “Type 30” 1928design is spread out amongst many different designs, not just the 8,000 and 10,000 gallon noninsulated, nonpressurized car types. So 15,570 total production is heavily diluted by car type.
And speaking of diluted, how many were built per year? This table will assess that:
The 1917design had ~DOUBLE the production pace of the “Type 30” 1928design. Yes, the 1928design had to contend with the depression, as well as the corresponding turmoil of demand for oil and similar products, but they also had to contend with “tooling” changes for the different tank car types they were constructing.
Is the 1917design a minority car? I think the GATC 1917design is probably a DRAW with the 1928design “Type 30”  at best.
Bruce, next time just say you wished Tangent would have done the "Type 30." Don't despair though, both will be in the Tangent product line.
David Lehlbach Tangent Scale Models


Tony Thompson
David Lehlbach wrote:
Actually, David, I was agreeing with Bruce's opinion that the Type 17 doesn't allow one to, as it were, "create a complete GATC fleet." As a 1953 modeler, I have four of your Type 17s myself and am happy to have them. If someone called you a "dumb manufacturer," I didn't notice it, and would have vigorously disputed it. Bruce seems to think that the Type 17's obsolete design by WW II (which it was) would have led to them disappearing, but tank cars typically had very long lives. There is ample photo documentation in the 1950s of lots of radialcourse tank cars still in service  which is why I have yours, along with some SP ones that I made with Archer rivets. And if a Type 30 is in our future, I am as ecstatic as anyone!Tony Thompson 

Bruce Smith
David,
In real life, I am a scientist. I form hypotheses based on the available evidence, and when that evidence changes, I am happy to adjust my hypothesis. The data you have provided is really interesting! Thank you. And I never ever considered you a "dumb manufacturer"!
Regards,
Bruce
PS. I am lookiong forward to that "type 30"!
From: main@RealSTMFC.groups.io <main@RealSTMFC.groups.io> on behalf of Tangent Scale Models via groups.io <tangentscalemodels@...>
Sent: Saturday, October 3, 2020 12:00 AM To: main@RealSTMFC.groups.io <main@RealSTMFC.groups.io> Subject: Re: [RealSTMFC] GATX fleet breakdown? Guys,
Thanks to Dave Parker for sharing his research from Railway Age tabulations and subsequent analysis on the likely GATC production numbers for the first years of General American production, including the subject cars here, the 1917Design tanks. (Bruce, the German American name was dropped in 1916).
I too have done my own research on this, and built my own business case for spending lots of money tooling the 1917tanks. Spoiler alert for Bruce Smith (and Tony Thompson who seemed to resoundingly agree): they are not “minority cars.” If you will indulge a “dumb manufacturer” (but one who does his homework) to weigh in, please read on.
First let’s look at the numbers. Here is the raw data of GATC tank car builds, by production year, compiled from Dave Parker’s 19171921 data and the stated production numbers in Epstein’s “A History of General American Transportation Corporation.” Also included is a key element, which is the body type.
Now when those numbers are aggregated, you can see the breakdowns by body type:
So you might say, you see! The 1917design is only 25%  there are more numerous GATC builds! Yes, that is true from a raw numbers standpoint, but let’s peel that onion a bit more, and look at how many carbodies were built by GATC for each frame design:
So is the 1917Design a “minority car?” A few comments:
But what about the “Type 30s!” Conversely, the 1928Design cars (dubbed “Type 30”) were produced in larger numbers at 43%, or 15,570 cars at least, possibly a few more in 1945 and 1928. But consider this. By 1928, based on market demand for specialized service tank cars, GATC had introduced many tank car size and type options. As the table above states, I count at least 30 different body types sitting on 1928design underframes (of varying lengths just to add to the complexity). Yes, the 8,000 and 10,000 noninsulated cars were significant cars, but there were many other significant cars as well, and in multiple body configurations:
This is the closest analysis we will get to figuring out whether the 1917design tank is a minority car. I think it is very clear it is not, since 2 car types dominated the total production of 9,079 cars. The “Type 30” 1928design is spread out amongst many different designs, not just the 8,000 and 10,000 gallon noninsulated, nonpressurized car types. So 15,570 total production is heavily diluted by car type.
And speaking of diluted, how many were built per year? This table will assess that:
The 1917design had ~DOUBLE the production pace of the “Type 30” 1928design. Yes, the 1928design had to contend with the depression, as well as the corresponding turmoil of demand for oil and similar products, but they also had to contend with “tooling” changes for the different tank car types they were constructing.
Is the 1917design a minority car? I think the GATC 1917design is probably a DRAW with the 1928design “Type 30”  at best.
Bruce, next time just say you wished Tangent would have done the "Type 30." Don't despair though, both will be in the Tangent product line.
David Lehlbach Tangent Scale Models


Dave Parker
All:
Many thanks to both Steve and David for jogging my feeble memory about the 192247 data in the Epstein book. I knew they were there, but had never gotten around to studying them. I want to make a few followup observations and comments. 1. First, just to reiterate my point that the Railway Age data reflect orders placed, not cars built, where as the Epstein tabulation reflects the latter. Also, as I understand the accompanying narratives in RA, orders from private lines were selfreported by the buyer, not the builder. The editors seem to have felt that most companies were quite assiduous about accurate reporting, but these data should probably be taken with a couple of grains of salt. The Epstein data are likely quite a bit "firmer". 2. I misspoke in an earlier post. While the October, 1919, ORER gives the GATX fleet as 4540 cars, the August tariff book shows something like 6500+ cars. I cannot account for this discrepancy, except to speculate that GA was "lazy" about sending current carcounts to the register. 3. David, your first table shows "Body Design", but a little further down the page your refer to them as "frame designs". I can easily spot the difference between the 1917 frame and the 1928, but I am somewhat fuzzy on what changes occurred in 1922 and 1926. I have heretofore thought of the transition from the 1917 to 1922 designs as being a tank change, i.e., the switch from radial to longitudinal courses. My sense from Ted's SEFCRM book is that a lot of this had to do with center tank anchors and bolster supports, but I have never seen the transitions enumerated in any detail. Can you help? 4. Also, I am naturally skeptical of the sharp cutoffs implied by the construction of your first table. Much of this is based on experience with the ACF tank cars of the 1920s. "Type 21" cars first appeared in 1920, and were built until 1929 at least (I recently finished a Shell car that was built 4/29). There are scattered occurrences of intermediate types (25, 26 IIRC) before the advent of the Type 27, very few of which where actually built in the 1920s. So, my guess would be that the GATC cars evolved in a similarly erratic manner. If the 1917 design involved a distinct frame design, do we know that the switch from radial to longitudinal courses matched up exactly with a change in the frame? Was there a length difference anywhere as was the case with the ACF 21 to 27 transition? 5. I did spend a bit more time poring over the 1919 tariff. In the latter half of the tabulation there are large blocks of 8000gal cars with 198gal domes, and these match up with the Tangent model.. These are almost certainly MCB Class III cars (IMO), and thus 1917 design cars. My best guess is that there were somewhere between 2000 and 2400 of these cars on the GATX roster in the summer of 1919, so that's a starting point as to abundance. There were also some 10,000gal cars with 270gal domes that seem likely to have been 1917 cars, but not nearly as many as the 8000gal version (I have not tried to count these yet). 6. One exercise that I have enjoyed with these 1917 GA cars is to see where they could fit into fleets of interest to me. The various (and very cool) schemes issued by Tangent thus far seldom line up with the combination of geography, industry, and era (1934) that I model, so I have dug around looking for better "fits" that can be created using undecs or kits. So, in addition to GATX cars themselves, I have focused on: Sinclair cars (1000 8000gal and 300 10,000gal cars purchased new; more were added later with secondhand purchases) UTLX (1000 cars initially. The Tangent model of this was a musthave, but only one. There were so many more UTLX V, X, and X3 cars out there!). Gulf (350 cars new but, disappointingly, they dropped out of the ORERs between 1926 and 1930) Barrett Tarvia (very cool asphalt cars mostly built by GA, but a bit tricky to sort out. Correct dome size is a significant issue here, but I will likely end up with one car). So far, that's about it for me. As I mentioned earlier, the Railway Age tabulations show a great many purchases of 1, 10, 25, or 50 cars by obscure (and a few notsoobscure) petroleum companies, so many of these would only show up in specialized, local/regional circumstances. And to reiterate David's point, many of these wound up back at GTAX (or UTLX, or Sinclair) after ~1930, so confirmation from photos, ORERs, and tariff books is really needed for accurate placement on 1940s and 1950s layouts. Again, I hope this is helpful and germane to the original post.  Dave Parker Swall Meadows, CA 

Garth Groff and Sally Sanford <mallardlodge1000@...>
Dave, Barrett Tarvia? Would these two photos be of help? This car is part of a private collection in East Barnet, Vermont. I photographed it (with permission) about 2000. Yours Aye, Garth Groff 🦆 All: 

Dave Parker
Garth:
I visited that same collection about 15 years after you did (more because of a boxcar there), and have a couple of pix of this BMX car. I will add yours to my album. At the time, I did not appreciate the significance that BMX (and GATX cars under lease) would take on for me, nor that Tangent would provide matching models for some. This particular car is significant because it is the first Barret 1917 design GA car that I have found in the 8000gal configuration. In general, 10,000gal cars were quite a bit more common in the Barrett fleet, at least in 1936. So, thanks for the memory jog! BTW, Barrett is not the easiest fleet to sort out because of leases under GATX reporting marks, and because of some uncertainty about what was purchased new versus secondhand. But it's a fun company to think about modeling, with widespread geographic utility. Thanks again.  Dave Parker Swall Meadows, CA 

David
I think we have enough information now to make a rough approximation of the GATX fleet composition in the late 1940s.
Assuming that the GATX WW1 fleet buildup (1651 cars in 1914 to 10806 in 1920) was supplied by GATX itself, that would be around 2700 cars built 191517 to the pre1917 GATX design and the transitional 1917design cars, plus 6500 cars built 191820 to the 1917 design made by Tangent. These numbers might be somewhat higher if older tanks were being retired, but I expect that is unlikely. The fleet stayed essentially constant through the mid1920s. There were likely some additions of the 1922 design to offset retirements, but probably not in large numbers. 19261932 saw the fleet grow to just under 25,000 cars: 9000 by acquisition, and 6000+ new construction (some of the 1926 design, but mostly Type 30s in 192930). The merged lines were generally a variety of builders, leaning toward AC&F cars. The big exception here is Standard Tank Line, whose 2827 cars would have been almost entirely STC radial and longitudinal tanks. The next big leap to around 37,000 cars came in 19367 with more acquisitions: 4662 Texaco tanks from a variety of builders (but these were still lettered TCX); around 6000 PTX cars (some highwalkway, mostly radial, and some longitudinal); about 2000 Conley cars from a variety of builders; 1200 P&G cars from a variety of builders; and 776 Canton cars that were mostly AC&F Type 27s. After that, the fleet size stayed fairly constant, though there were likely some additions of specialized cars and retirements of older and smaller cars built before 1915 or so. So, very roughly: 2700 pre1917 and transition 6500 Type 1917 design a few hundred to maybe 1000, 1922 design 6200 or so: many ACF, some GAT, STC, PTC 2800 STC design 2000 1926 design 4000 Type 30 design 6000 PTC designs 3200 or so: many ACF, some GAT, STC, PTC 4662 TCX cars: many ACF, some GAT, STC, PTC 600+ ACF Type 27 maybe 12000 later Type 30s, mostly specialized cars? This is close to 40,000 cars; there would have been some retirements of older equipment along the way. David Thompson 

Ken Adams
A fantastic discussion. Loaded with information and I am looking forward to the Tangent GATC type 30 hopefully in both 8K and 10K versions with AB brakes.
Shifting my plain black tank fleet emphasis to GATX from UTLX. Now I just have to complete the 3 SP O5013's that have been under construction for 56 months.  Ken Adams Still in splendid Shelter In Place solitude, about half way up Walnut Creek 

Ian Cranstone
I had a few thoughts visavis tracking the GATX fleet based on my experiences in working through understanding the Imperial Oil/Transit Company Ltd. to Products Tank Line of Canada fleet, and the Canadian General Transit Company fleet
1) Those 1917 design GATC cars lasted a long time. CGTX had a number handed down from parent GATX in the 1930s and 1940s (and possibly as late as the 1950s). Based upon ORER and Tank Car Capacity tariffs, it would seem that a lot of them lasted into the 1960s. Similarly, the ones built new for Imperial Oil seem to have served subsequent owner Products Tank Line of Canada about as long. 2) Although it is difficult to understand tank car fleets based on ORER listings (and some are particularly difficult — not mentioning the Products Tank Line of Canada in particular), it is very possible to track cars through the various issues of the Tank Car Capacities tariff, and I was able to do a lot of this with the Imperial Oil Ltd./Transit Company Ltd. fleet to Products Tank Line of Canada. Many of their cars varied slightly in terms of both shell and dome capacity, and in many cases the combination of the two was unique to one or only a few cars. Fortunately for me, Products Tank Line of Canada made it easier by carefully placing them into UTLX series in their original numbering order, regardless of the predecessors random renumbering into new series. I don’t know that GATX did the same, but one can hope. If the ORER is helpful in terms of understanding which fleets were acquired by GATX, there is a good place to start, and with the 1919, 1936, 1955 and 1970 TCCs around to compare to each other, there might be a very real possibility of coming to a reasonable understanding of the fleet, and its origins. 

Bruce Smith
David, Dave, Folks,
All this discussion of GATC tank cars has me looking at my fleet to see how I might both take advantage of Tangents most recent announcement and adjust my fleet. Are there any indications of a breakdown between car gallonages within a type? For example, is there a feeling on the ration of 8K to 10K tanks in the 1917 cars? I note that David says "most" were one or the other. What about the numbers of different styles within the 1928 design? Regards, Bruce Smith Auburn, AL 

Dave Parker
Bruce:
Such a breakdown, even if possible, would be a very daunting task just due to the size of the GATX fleet. If anybody takes a stab at it, my hat is off to them! I did spend a few minutes thumbing through the 1919 and 1936 tariffs, just counting pages dominated by each car size. In 1936 (~24,000 cars running under GATX), I'd guesstimate that 8000gal cars outnumbered 10,000gals by about 2:1. A small number of 12,000gal cars, and rather few under 8000. In 1919, my sense is that it was similar, but there were more 6000 and 7000gal cars that presumably did not persist into the 1930s. I did not look at PGX, CTTX, or PennConley (including TCX)  only at GATX reporting marks in '36. Don't know if this helps much. GATX is a bear to track over time. OTOH, if anybody is interested in Barrett's fleet of ~1600 asphalt cars running under BMX, I am getting a halfdecent handle there. The most obvious thing is the paucity of 8000gal cars and the dominance of 10,000gals. And "no" multicompartments! Given his interest in GATC, David might have more to add.  Dave Parker Swall Meadows, CA 
