Why were these locos f7 8s or 9s called cab units?
I could be wrong, but I’ve always suspected the term originated from the difference between “controless” “B” units versus their “A” unit counterparts.
The “A” units were cab units, while the “B” units had no such permanant operators control station. Then the term just sort of got genericized, like “kleenex”
Of course, “B” units do have rudementary control stations that allow them to be hostled around the yard, etc, but that is a seperate story.
Once road switchers came into road use, there was a need to distinguish between the hood units and the units that had the frame as part of the side wall. Cab unit covers the earlier units well, as the cab roof continues back over the rest of the locomotive.
There was no F8.
There were E8’s, any idea why they skipped the F8 model designation?
Doug
To my knowledge F8’s were never built, F7’s were the last hurrah for the F-units, the more versitile and less expensive hood units like the Geeps killed the cab units just as surely as the cab units killed steam.
Cab units? Here at the “Fortress Firelock” Lady Firestorm and I call them “Superman diesels.” Wonder why? Well, check this out!
https://www.youtube.com/watch?v=p0swAKS-5qA
Get the picture? As a matter of fact when we were in high school back in the early 1970’s us kids called those big blocky cars like the one that goes over the cliff “Superman cars,” but that’s another story.
That show sure was popular with us Boomers!
But there were F9s. 99 A’s and 156 B’s. Visually they were virtually indistinguishable from the late F7’s.
90 very similar FP9’s were built as well.
Good to know, it’s a wasted day if you don’t learn something new.
But I imagine there still never were any F8’s.
Nor were any F1’s, F4’s or F6’s ever built. The F10’s were rebuilt F3’s. There’s still a few of them still running.
I never understood why it was believed that cab units were optimum for freight use. Seems a logical evolution from steam, would’ve been the road switcher to begin with.
Always thought the RR’s were attempting to emulate airliners in appearance with cab units. About all these units had going was their looks.
Because the “F” units were the original road diesel, and came out 10 years before the “GP” units.
The FT was released, IIRC, in 1939, the GP7, the first of the GP’s was released in IIRC, October of 1949, for 10 years there WASN’T any other choice, at least from EMD. The Alco RS 1 came out in 1941, so even there it was 2 years before the railroads had a road switcher option.
The road switcher simply wasn’t an option, “To Begin With”.
Doug
The first diesel switchers were box cabs. Then some switchers came out with the single visibiliy cab. There were still some early box cab road diesels (lke box cab electrics). The early cab units were more like streamlined box cabs. Since they were intended as multiple units, there ws no reason for bi-directional vision as with GP road switchers which might be used as single units.
Actually, it was longer than that. Wartime restrictions undoubtedly delayed the development of the road switcher (RS), among other things. EMD was actually behind ALCO in developing the road switcher.
Remember also that the diesel locomotive as we know it evolved in the Art-Deco streamlined era of the 1930s, and the first successful units were all intended for passenger service, notably as power cars for articulated trainsets like Burlington’s Zephyrs. The E and F units evolved from these, and naturally came in the same streamlined eye-catching carbody, which happens to be the same shape as a Budd or Pullman-standard lightweight car.
The “hood unit” or roadswitcher body type came about after the shortcomings of the streamlined body became apparent, notably the restricted visibility of the engineer when switching. EMD’s first attempt to rectify this was the BL2, which ironically ended up being the worst of both worlds and was unsuccessful as a result.
As Doug noted ALCO was ahead of the curve with this, as they were with so many other diesel locomotive innovations, but better reliability and the War Production Board’s allocations gave EMD a big boost ahead of the other builders.
EDIT: I see Larry beat me to the punch
I had forgotten about the wartime restrictions, I was just making the point that when the F u its were gainig popularity, the Raod Switcher wasn’t an option yet.
There is a story that Dick Dilworth, with EMD didn’t even anticipate the GP 7’s being used in mainline service, but had commented that the GP’s were so “Ugly” (his words, not mine) that he expected that they would be “Hidden” on branch lines and in yards where nobody would see them.
To somewhat illustrate the point of the GP’s evolution timing, the GP 7 was designated as a “7” model because it shared the same machinery ie, Prime Mover, Generator, Traction Motors and I believe most of the electrical gear, as the F 7, the main differences, were the frame and body.
What railroad is that - Southern Pacific?
- PDN.
Yes those were SP locomotives & trains shown.
My memory of the Superman opening credits pictured a shot of the Daylight steam locomotive, not diesel.
The original episodes were shot in black and white and had a publicity shot of a GS with single headlight … even as a kid I thought it looked fat with that arrangement.
When they went to color, they shot what was available then… with good, saturated color if my childhood memory is not exaggerating. That was I believe E units in Daylight colors, a beautiful train … but ISTR single-note horns; could that be right?
The original episodes were shot in black and white and had a publicity shot of a GS with single headlight … even as a kid I thought it looked fat with that arrangement.
When they went to color, they shot what was available then… with good, saturated color if my childhood memory is not exaggerating. That was I believe E units in Daylight colors, a beautiful train … but ISTR single-note horns; could that be right?
in those days of the little “C” in TV Guide to show the rare color programs, you never knew whether you’d get a B&W or color episode.
It seems that EMD wanted to align the model designations to match with the introduction of the 567C engine, which was the most major upgrade of the 567 series.
So since the E-8 used the 567B engine but was otherwise a significant upgrade from the E-7, the lowest available number was 9 for the E-9.
Accordingly, the upgrade of the F-7 became the F-9 and the upgrade of the GP-7 became the GP-9 and the SD-7 changed to the SD-9.
After this the designations became based on horsepower with the introduction of turbochargers. No new E or F unit types were introduced, but there were GP-18, GP-20, SD-18 and SD-24.
With the next upgrade, the loco intended to be the GP-22 became the GP-30 and the numbers no longer related to power.
Peter