DRGW Prospector questions

Why were the Alcos pulled from Zephyr service?

That's right.

It's often assumed that the PAs' problems cropped up early and they were removed from Zephyr service almost immediately, but this simply isn't the case. Certainly the Alcos had more than their share of service failures; that's well documented from the experience of other roads. They were also difficult and expensive to maintain. Still, the Alcos hung in there in Zephyr service for far longer than their negatives would seem to justify. What interests me is not why the Grande took the Alcos off the Zephyr so soon. I would like to turn this question on its head: Why didn't they do so sooner?

The Grande continued to use the Alcos in California Zephyr service throughout most of the train's first decade even though there were plenty of EMD power sets around that were equipped with steam generators for passenger service. And that was true from the day the Alcos arrived! Three A-B-B-A sets of F3s (5521-4, 5531-4, 5541-4), rated at the same 6,000 horsepower delivered by a three-unit PA-PB-PA set, were already on the property, having been delivered in November, 1946, two months before the Alco's January, 1947 arrival. What's more, according to the Grande's own formula, these sets had significantly higher tractive effort than the Alcos. What was the problem with the F3 sets that made the Alcos continue to look good as the mainstay of Zephyr service?

It's important to remember that the 1946 Alco order took place in the context of friction between the Grande and EMD; the Grande accused EMD of overstating it horsepower ratings. With plans for the Zephyr and Prospector taking shape, the Grande had already ordered three sets of F3s that were specifically intended for passenger service, but management feared that the F3 sets would turn out to be gutless, and they wouldn't be able to keep the Zephyr on schedule. As Grande management knew very well, SP was having similar misgivings concerning the use of EMD power on its planned Cascade services, which would have to cope with similarly mountainous conditions. (SP also ordered PA/PBs -- six sets, in fact.) So the decision to go with the Alcos was intended to send a rather pointed message to EMD. And with both Alcos and F3s on the property, and after testing both extensively on the Zephy's predecessor (the Exposition Flyer), the Grande gave the Alcos the nod. The F3s were relegated to a backup role, although at least one of the F3 sets -- 5521-4 -- seems to have been part of a regular rotation schedule, presumably designed to free up time for maintenance. (Remember that running the California Zephyr required the Grande to keep *two* power sets running every day; typically, they'd pass each other in Glenwood Canyon. At least one additional power set would be needed just to cope with routine maintenance.)

The Alcos faced competition from lots of other EMD possibilities. Also available for backup service were four sets of FTs (5481-4, 5491-4, 5501-4, 5511-4) that were equipped with steam generators, one (5481-4) as delivered and three more due to 1948 service upgrades; 1949 saw the arrival of three similarly equipped F7s (5551-4, 5561-4, 5571-4); a fourth F7 set was equipped for passenger service (5581-4) using steam generators removed from FTs in 1953.

The "underpowered" F3s turned out to have more power than initially thought. By the early 1950s, the Grande had figured out that the F3s weren't geared correctly; initially they were geared according to EMD's recommendation for passenger service, 61:16. Just when this was realized isn't known; however, by 1948 there were F7s on the property that, while purchased mainly for freight service and geared accordingly (62:15), could do 70 mph with a passenger consist in tow--and without frying traction motors, as EMD had warned. In 1953, the F3s were regeared to 62:15, picking up an additional 10,000 pounds of tractive effort for each four-unit set. Still, the Alcos got the nod for regular Zephyr service.

Although the two Alco power sets seem to have been favored well into the mid-1950s and beyond, by 1952 there was an important new development: the three participating roads decided to drop the notion that the 11-car consist was sacrosanct. They purchased 22 additional cars -- ten with Zephyr lettering -- that were compatible with the Zephyr in looks and functionality. The result was that, during the summers and holidays, the Zephyr would often run with more than the classic 11-car consist. I believe that the Grande was happy enough with the Alcos' performance with the previously fixed 11-car consist, but there wasn't any way a three-unit Alco set could cope with 16 cars. At the same time, with dozens of F7s in freight service, the Grande was learning to break away from the former mindset in which a four-unit A-B-B-A coupling was sacrosanct. The F3s made inroads into Zephyr service prior to the mid-1950s, I believe, because the Grande could easily assemble a five-unit set of F units when needed by adding a properly equipped F7B unit for an A-B-B-B-A power set. There is good evidence of this in the photographic record. Even so, the Alcos still got the nod for 11-car consists -- or shorter ones; during the winters, the Zephyr sometimes ran with as few as 8 cars.

Another important part of this story was the 1955 arrival of a four-unit set of passenger service F9s (geared 62:15, of course), which delivered 1000 more horses (7000 total) than the F3 sets (6000) -- which meant that a single A-B-B-A set could handle all but the lengthiest Zephyr consists. Also delivered in 1955 were two F9Bs, which (after some experimentation and a bit of renumbering) were added to a steam-generator-equipped F7 set that was initially delivered with three-units, resulting in a "near-F9" set: 5751 (F7A), 5752 (F9B), 5753 (F9B), and 5754 (F7A). So by late 1955, the Grande had two F9 or F7/F9 A-B-B-A sets that had sufficient horsepower to handle most Zephyr consists without having to scramble around to find an extra B unit. But even this development wouldn't have necessarily resulted in the Alcos' being yanked off the Zephyr; it was the F3s, not the Alcos, that seem to have been displaced by the F9s, initially.

So what explains the Alcos' demotion? I think it's this: Even as the Zephyr was getting longer, the Grandes' other trains were getting shorter -- even to the point that they could be run with a single A unit. The trouble is that the Grande had only two passenger service F units equipped with steam generators, and they were tiny ones meant for reserve service. As the 1950s wore on, the Royal Gorge and Mountaineer shrank to the point that they would need, at most, a couple of units, and the Yampa Valley Mail needed only one. So the PAs, with their large steam generators and horsepower edge over F units, would have looked very attractive for this service. To spread the steam generating capacity around, the PAs were seldom, if ever, paired with PBs but rather with F7B units; likewise, PBs ran with F7As. Famously, EMD was tripped up by this practice when it published a publicity photograph featuring a Grande F7A unit powering the Royal Gorge -- but the B unit is an Alco PB! I think an additional facet of this power-distribution scheme is the well-known fact that train crews regard the PAs as "hot rods" with excellent acceleration; if you had to go with two units, making one of them a PA or PB added spice to an otherwise bland pairing.

By 1965, there was no longer a need for the PBs, which suffered a an ignomious fate -- their prime movers were removed and they were converted into steam generator cars. The PAs hung around until the last of the short trains was canceled. The picture, in sum, doesn't add up to the Grande getting rid of Alcos because of mechanical problems. On the contrary, the Alco story on the Rio Grande testifies to the challenges of matching available equipment to rapidly changing motive power needs.

--Bryan Pfaffenberger
Univ. of Virginia