Class 55 55017 Durham Light Infantry
David
But, what you have to remember is that that these locos only achieved that HP rating because they had two prime movers under the hood!
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That is as may be, but did what they were built for, and more.
David
e9 was 2400hp. PA 2000hp from one prime mover. Several single-engine passenger engines were specified in the mid- to -late Fifties (the RSD-7 and RSD-15, for example) One could argue that the Krauss-Maffei Amerika-Loks, had they been built for passenger, would have been 2000hp per engine.
The follow-on to the E9 was the SDP35, then the SDP45 and FP45, only a couple of years later than the 55s and 300 more horsepower; the stillborn Alco equivalent was the C636P, also 3600hp.
The American equivalent of the 55s was the stillborn Ingalls Shipbuilding 2000hp passenger unit, which was originally designed with two heavy Superior diesels but could have accommodated more capable engines with better horsepower-to-weight ratio fairly easily. These were almost ridiculously light, with the idea they would be capable of very high road speed with light axle loadings – the Naperville wreck and subsequent ICC order on signals and train control making that market segment functionally DOA.
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If we’re talking about power from a single prime mover, it would be hard to beat the UP’s GTELs with 4500HP one the first generation and 8500HP for the second generation.
I’d wonder how well the Deltics would work under American railroad usage, where being able to run 2000+ miles with just refueling was more important than getting the ultimate power to weight ratio. For passenger work, Westinghouse’s GTEL would have made more sense for the power to weight ratio. The exhaust heat from the turbines could have been used to generate a lot of steam for heating and cooling (with steam ejector A/C).
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UP never had a GTEL for their passenger service – which is strange because they tried Steamotive steam turbines a decade earlier for passenger only. I do not think you could have run Domeliner anything behind one of those burning heavy oil – and they were uneconomical burning anything else.
As you note, the Blue Goose was a different story, but I suspect one of the free-piston designs would have been better still.
While it is difficult to figure out the exact truth behind the PRR hype, the ‘revised’ version of the V1 with Bowes drive (which suited it for passenger service, hence the fancy shell design) started at 8000hp (2 turbines) and had reached 9000 nominal hp by the late Forties (although the water rate to sustain that horsepower was more than a tad unworkable when you actually looked at the mass flow required…) THAT would have been an interesting locomotive for high-speed trains.
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I don’t think that’s right. I just read O S Nock’s account of the May 8 1978 intro of the Intercity 125s and they replaced the Deltics. It was a great article as it had speed logs over 50 years span from the A4 Atlantics to the Deltics and lastly on the newly launched 125s. Electrification to Edinburgh didn’t occur until the 90s. But the line was electrified from London to the suburbs by 1978.
Ralph Fiennes of BR was quoting as saying he was very glad that English Electric was so forceful in pushing the Deltic on a reluctant management. It saved British railways from the onslaught of jets and high speed motorways. The Deltics did LON-EDI in 5 1/2 hours. I just googled a drive and it would take 7 1/2 assuming both my gas tank and bladder would last that long!
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Looking at the freaking design of the Deltec engine all I am going to say is this. While it worked for the British who could put it into the shop as needed to tinker on it and keep them running right. The old KISS principal still wins in the end. 18 cylinders 36 pistons lord help your machinists if one of those 3 crankshafts jumped time.
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Some are still running. A delight to see.
David
[quote=“haroldbenton, post:29, topic:320362”]
18 cylinders 36 pistons lord help your machinists if one of those 3 crankshafts jumped time.[/quote]
You’d have to strip those gears to get the crankshafts out of sync. I put a gear drive on my 6.5TD to avoid any chain stretch effects – I confess I liked the Ferrari-style whine…
Much as I hate to say it (as an APT-E proponent since the early seventies… when I saw it illustrated in the same issue of Trains that had the Big Emmas) but the best it really got was the Paxman Valentas in the HSTs. Honorable mention, I suppose, to the MTU replacements.
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I didn’t say it wasn’t near impossible but I’ve seen enough weird failures in my lifetime that proves if man designed it Mr Murphy always finds a way to break the freaking thing. Like my 2019 Ford Fusion that I just returned to the finance company this last week. 1.5 eco-tech engine that snapped the intake manifold timing gear off inside the camshaft. Now on a normal engine not that big of a deal. However on the 1.5 there’s no pin or keyway holding the cam in place with the gear. It suffered from intake valves meeting with the pistons in 1 and 3 and cracked the head. 7 grand to fix it. We paid 1500 down instead on a 2017 Pacifica and walked away with the finance company’s okay. We have gapp on the loan and the dealership has declared it a mechanical total.
The Deltic is a marvelous example of inspired packaging, resulting in what should be a very rigid engine block. With the arrangement of the opposed pistons, I would also assume that it would be very smooth running. OTOH, I wouldn’t want to have any connection with maintaining those beasts.
P&W’s Wasp Major and Wright’s Turbo Compound both put out as much power as the Deltic and both were known for being maintenance nightmares.
As unlikely as it sounds, I have some experience with the Napier “Deltic”. In 1969 I was involved with a scheme to attract engineering students to the Royal Australian Navy. A few of us were taken to sea on HMAS Snipe, an ex-Royal Navy “Ton” class minesweeper. This had two of the 1650 HP T18 Deltics for propulsion, and a turbocharged T9 for the pulse generator used to detonate mines. The T18s were started by cartridge, basically a shotgun cartridge less the shot. We had a scratch crew rounded up for the day, but fortunately the Chief MTP actually knew what he was doing. We started the port engine first but that used three of the four cartridges we had. The Chief assured me he could start the starboard engine by clutching it to the propeller when we were under way, but I didn’t like the idea of backing away from the wharf with only one screw, then trying to turn in the inlet going astern on one engine. Our luck held and the starboard engine burst into life on the first try.
The Deltics had replaced older and even less reliable Crossley engines, partly because they had a much smaller magnetic signature being partly made from aluminium castings.
Later in the month I was given a week to spend in the Deltic Workshop. The engines were repaired by replacement as far as the ships were concerned, and the engines were overhauled every 3000 hours operation, if my memory is correct. The workshop carried out the overhaul to Napier specifications, but I was told that there were no visible signs of wear on any component at stripdown after 3000 hours.
Peter
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Thanks for posting, Peter. Class 55 (Deltics) are my favourite locomotives.
David
I first visited the UK in late 1973. I stayed with friends in Cockfosters, so my first journey in London was from Hounslow West near Heathrow to the far end of the Piccadilly Line. The street ran east west down a steep hill to the East Coast main line, and we could see and hear the Class 55s as they climbed up through Oakleigh Park. They were nearly all renumbered as TOPS Class 55 and were plain blue with yellow ends.
Peter
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People see the picture of All Those Gears and they think the Deltic has to be from the same school of (over)engineering that gave us the Napier Sabre and the Caprotti nightmare box.
The Deltic us just three 60-degree V12s joined at their cylinder decks. Interestingly two of these rotate one way, and the third the other way, which improves concerns with balance, but as there is no valve gear this is incidental mechanically. Making the gears would involve a one-time expense, but I wouldn’t expect them to wear badly in service.
The fun comes in when you consider there are many of the issues with the Fairbanks-Morse OP involved with the Deltic, starting with crankshaft lubrication and pistons working at an angle so some load is handled on the ‘down’ side of the rings and skirts. Blowby problems from worn or scuffed bores involve the same nightmare disassembly (which is one of the chief reasons these were removed as a unit for maintenance).
I don’t know what kind of air filtration the 55s had in service, but it would have to be pretty good, and maintained well. Same with the quality of the lube oil, something that can be ignored on many medium-speed diesels but would have to be watched very carefully especially for hard particles that might damage the gears.
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Bob, the mention of “sound” the engine produced reminded me of the 2 stroke EMD engines. Which in turn called up the sweet sound Kubota small hp engines had in the equipment I was around during my retirement job. I guess in the real world, sound verses horsepower, maintainance, mpg, etc. has to win out in choice of engine prime mover. endmrw0205251339
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I love the sound of Class 55s
David
Weren’t the Deltics also 2 strokers. They always have that throaty roar. I lived along on the CNW NW line back in the 80s. The EMD F7s pulling the commutes would lull me to sleep.