I can’t help but wonder, considering the supposed issue with some of the SDP40Fs, whether there might be emergent behavior from the water tankage at some critical higher speeds, including on curve entry and exit. Testing might need to be a little protracted with different combinations of ‘parameters’ to make the behavior appear…
Yes, some 20 or 30 years from now, some group of enthusiasts will want to construct from scratch an SDP40F, forming an entity called the “SDP40F Trust”, and one of their objectives will be resolving the sloshing-in-the-water-tanks-to-supply-the-steam-generators historical question (whether the SDP40F only sloshed at low speeds or if it suffered from a high-speed sloshing phenomenon) and to counteract the dismissive position of railroad historians that the SDP40F was “a failure”?[8-|]
That’s pretty funny!
Was baffling ever applied to the SDP 40’s water tanks?
The issue was the shape of the tank: thin and upright. Baffling would have been comparatively ineffective against what was a coupling between the lateral compliance characteristics of the hollow-bolster Flexicoil trucks and the water mass up high.
At one time there was a fairly detailed discussion on the Web of this problem and, as I recall, its resolution. I don’t remember if this was a priority to replace steam with HEP, but I suspect it did not hinder the effort… [;)]
Never had any experience with the SDP40’s
All the other steam boiler engines I have had experience with had the water carried in a tank similer to and in the location of the fuel tanks - thus low in the framework of the engines structure.
As a layman - what were the engineers thinking putting that much weight that high up in the engine? Water is not light.
It is difficult for me to figure that out. As I recall, the excuse had to do with relative ease of conversion to pure freight use – they shoehorned the tank where it could fit rather than compromise the ‘usual’ area under the frame between the trucks where the water tankage would be hung at the expense of fuel.
Dave Goding knows more than I do about Flexicoil in general and hollow-bolster in particular, and I’m sure EMD was involved figuring out where the problem arose.
I’ve actually read the SDP40F investigation report, but some years ago.
I might still have a copy.
However, there were a number of points not often mentioned. The derailments were all in the Eastern states on track that was not up to the highest standard. No derailment ever occurred on the Santa Fe or on the Union Pacific. The SDP40Fs were the heaviest passenger locomotives used on the tracks where they
There was a SDP40A proposed with twin steam geneators or double sized steam geneators. Gary
Presumably on the longer frame with the second generator in the space ‘opened up’ by the shorter V16?
The working idea would presumably be that this would give the effect of a heater car for a long consist without the full length and tare weight of one. It is interesting to consider what the effect of DPU or even early Locotrol might have been if applied to something like a City of Anywhere consist using a trailing unit with, say, the 3300hp E3A engine common to a Centennial and two SGs.
There is also the interesting possibility of ‘hybrid’ implementation of HEP using a genset in one SG position while retaining the other for ‘legacy compatibility’.
A railroad could order an F3A with a steam generator, but there was very limited room for water - I forget the exact numbers, but it was only like 1/4 what you could carry in a B-unit. A railroad in a cold weather area could generally only use an A unit by itself on a passenger train if it was a very short run like commuter service. That’s why EMD came up with the FP series, F units stretched out to fit the same water tanks as an F B-unit.
Anyway, I don’t think just having that steam generator would require a lot of extensive testing for high speed operation?
The limited water capacity with F3’s equipped with steam generators was one of the principle reasons that the B&O stopped using them on their ‘long distance’ passenger runs.
From living at the B&O’s divison point of Garrett, IN for several year and being in contact with numerous personnel - when the F3’s were used on passenger runs out of Chicago - they would be out of water upon arrival at Garrett. The units would be serviced at the Robey Street coach yards, move their train to Grand Central Station to await a On Time departure and then normally take three hours to Garrett.
Would the proposed FL9 have been better at solving the problem of water. Gary
FL9 had extra weight-bearing capacity as well as carbody length… but there would be little point in providing the additional structure merely for additional steam-generator water.
Absent the need for third rail, such a locomotive could have used a ‘normal’ swing-hanger A-1-A EMD truck at the rear instead of the Flexicoil, and retained the swing-hanger B truck of the two prototypes at the front. A very logical step here might have been the use of a turbo V16 to get higher unit horsepower comparable to, say, a FM CPA24. However I suspect the passenger market for new power was pointedly not directed at such a thing by the early '60s.
It was 75 years ago this month the EMD began building F units again. The last FTs were built in November 1945. Then a United Auto Workers strike shut down EMD until March 13, 1946, but no additional units of any kind were built until April presumably because of a steel strike and lack of parts. The Engineering department would have had plenty of time to test the D8B generator in the 291 test set. Tonnage ratings would have been established for the new F2s and instructions on operating with FTs would have been written. Operator Manuals for the F2 were published on June 1, 1946 in advance of the July production of 43 F2A units. Of the 43 new F2As, a total of 39 were built to work with FTs, another two were low geared units for use on a light rail short line and two were passenger units.
Ed in Kentucky