I had a cab ride in one at a steady 100mph from London to Newcastle at the time the new poles for the future caternary were all ready in place. A very thrilling experience. Reading Juniatha’s comments on the Faribanks-Morse opposed-piston design, I would value her analysis of the Delta with three crankshafts and six pistons where one is usual! Other’s comments also appreciated.
One of the very smoothest riding diesels I have ever had the privilege of riding. Not any noisier than a GP-7.
Yes, I did ride Newcastle’s “light rail” (so-called, mostly ex RR RofW, mu, train-door, high platforms, really a Meto, not light rail) system and visited the National Railway Museum.
I my view the most remarkable thing about the Delta diesels was : they succeeded in making them work reliably and at an appreciable high power output rate - although when in England I have heard sturdy steam buffs say a Coronation Pacific in good shape and run by a determined crew was a tantamount competitor - at least in the upper speed range , I understand .
What it didn’t prove was it should inevitably take a delta concept of IC piston engine to do that . You might also have chosen a multi-row radial engine - such as , say a six row pack of nine cylinders , water cooled for improved and more leveled cooling of the dense cluster of 54 cylinders and pistons ; six rows in order to keep overall diameter more concise to allow for inspection galleries both sides within loading gauge and to better comply to principally longitudinal extension of space in a locomotive . I’m sure with duly careful design and testing , with decent degree of care and maintenance it could be made to succeed and would be a really bad power pack , just great to hear and see working at full cry on its elevated engine foundation while the loco speeds along at …
Or , in the end when it comes to rational - not radial least radical - design I would shake off dreams of wild clusters of cylinders all working on a central crank shaft in a complex assembly of an all hot engine block with intriguing network of intake and exhaust lines … and design a big bullish V 16 or V 20 with power to spare which will do daily work mostly just humming contently along , only raising its grim howling when fully extended on rising grade …
The “multi-row radial engine” sounds a bit like the description of the “pancake” engines used on some post-WW2 USN ships and “boats”, with the Albacore being the prime example of the latter. I would assume that a locomotive engine would use a somewhat more rigid crankshaft than typical for aircraft radials, as the Wasp Major had rather severe problems with torsional vibrations at reduced engine RPM’s that weren’t present in the Double Wasp or Wright turbo compound.
I appreciate both of the above answers, and both are valuable. The thread on “locomotives that modelers prefer” has a posting that says that all repair on the Deltas and major overhauls meant simply removing the diesel, putting in one ready for service, and then working on the diesel outside the locomotive. That was the service routine that kept the locomotives in reliable service. Does anyone think that doing this as a routine proceedure would be possible on a North American railroad?
In 1968 I was fortunate enough to spend a day at sea in HMAS Snipe, a former Royal Navy minesweeper powered by two 18 cylinder Deltic engines, with a third nine cylinder generator for the magnetic sweep. While the locomotive engines could be started by motoring the generator, the marine engines were started by discharging a cartridge into the engine (a shotgun cartridge minus the shot). On this occasion we had four cartridges and it took three attempts to get the starboard engine running. I had all my fingers crossed literally when we fired the last cartridge in the port engine but it fired up straight away.
We spent the day towing a gunnery target for HMAS Brisbane (a DDG-2 class destroyer with 5"54 calibre guns). It was standing off at fifteen nautical miles and the projectile had splashed down before we heard the gun fire.
Later I spent a week in the Deltic maintenance shop. The engines were overhauled at about 3000 hours although I was assured that they were generally in perfect condition, showing no wear on any components.
Later still, in 1973, I was living in London, in Cockfosters, and my street led down to the Great Northern main line. When leaving or arriving, I would often hear a northbound Deltic heading upgrade and I’d always wait to watch it go by.
The engine was, as D K Brown wrote in “Rebuilding the Royal Navy” “the size of the First Sea Lord’s desk”, although quite a bit heavier and it was very easily removed for overhaul, either from ships or locomotives.
The parts were small and light and easily handled (the engine “block” was aluminium) and there were few parts that could be serviced in place anyway.
While a radial engine of the same power output could naturally be more sturdily built for use in locomotives than in aviation and problems with proper frequency vibration could be avoided and would be much less critical to start with because of lower rpm level of running of typical locomotive diesels as compared to aviation gas engines , I did not propose to use one in railraod traction !
My example was to say : neither was the delta concept of motor in the Deltic class responsible for high output of these units nor was it a sine qua non – if you wanted you __could__ (!!!) even design a radial engine for the same purpose and with qualified design and maintenance (!!) it could be made successful ( that doesn’t say it has to !)
Mind that I did __not__ propose to actually use one in a locomotive .
Daveklepper ,
Taking out the motor and replacing it by an overhauled one from stock is a practice regularly resorted to in classified overhauls and in running repairs when necessary ; mind however , not every diesel shed is equipped with (a) overhead crane and heavy tooling for pulling / installing motors (b) has diesel motors in spare for replaceme
It wasn’t my intention to say a radial engine would be a bad idea, but more of what would have to be changed from aviation practice, where weight is far more critical than locomotive practice. A related example would be the Liberty engine of 1918, a 45 degree V-12 that had torsional vibration problems with the crankshaft, while the Alco 251 V-12 engine was seemingly free of these problems even though it shared the 45 degree angle between cylinder banks with the Liberty engine.
As for radial engines in locomotives, it’s probably not the best arrangement, but not necessarily a bad arrangement.
Once again, you are getting all blown up over nothing! Nowhere in M636C’s post does he say anything like you think and I do not read anything in his post that would even slightly suggest that he has “some personal headache with your postings”. I think you are the one who is way off base and suggest that you offer an apology to him and the forum for your comments.
BTW, the only time that I see that the word “always” was used in this entire thread is when M636C said “I would often hear a northbound Deltic heading upgrade and I’d always wait to watch it go by.”
Your insights can be very educating to the forum, however, I would suggest that you leave the paranoia on your desktop.
Ok , so I drop the >> headache << point . However to explain the >> nothing << I got ever so slightly annoyed about : The user I commented on wrote
Juniatha spoke of radial engines. The best known of these is the Russian Zvezda M503 (42 cylinder seven row radial) and M520 (56 cylinder seven row radial).
That’s in German but Google gives a reasonable translation.
These engines required overhaul at 500 hours, six times as often as the original recommendation for the Napier Deltic. Having no valves as compared to 224 for the M520 must help. <<
That was an abusive contorsion of my concerned paragraph in that the commenting user twisted what I clearly had marked as → a theoretical example to explain nothing else but ‘any’ concept of motor can be made a success or can be made to fail ← into a serious proposal . Against that faulty interpretation the user put up his aberrant idea the Deltic with their delta shaped engine was superior because of that unique triple crankshaft motor . Or in straight words : 3000 hrs because of three crank axles , suggesting the three axles are essential for success of these locomotives suggesting a conventional V type motor with but one crankshaft will only stand 1000 hrs and a radial one will relate to that with but half the hrs again . In reality there is no such relation at all .
He draws that from totally crocked comparison by pointing at
To get back to the Deltic topic, it is interesting to note that it apparently the DP1 was almost tested in Canada. If produced, I think the powerplants would not have stood up considering North American maintenance, and they might have found themselves with a 567 rather quickly…[:-^]
I think I should say that I was not intending to attack Juniatha.
Since she raised the subject of a radial diesel engine, I thought I would give an example of an existing engine of that type.
As far as I know the Zvezda M503 was never used in a locomotive. Three M503s were used in the Soviet “Osa” class guided missile patrol boats. As Dave probably recalls one such boat in Egyptian service sank the Israeli destroyer “Eilat” with an SSN-2 “Styx” missile, the first example of this type of warfare. Ironically I understand the Egyptian boat was stationary in Alexandria harbour when it fired the missile.
But to return to the Deltic.
One thing to remember is the need for a high power to weight ratio.
This engine was designed by Napier at Admiralty request during World War II specifically to power motor torpedo boats which had previously used gasoline engines with the attendant risk of fire resulting from battle damage.
The production Deltic class 55 locomotives weighed only 99 long tons (111 US tons) and were carried on six axles. They were introduced at a time when British Rail were discovering that damage to track increased dramatically when high axle loads and high speeds were combined.
Remembering that the prototype DP1 was introduced in 1955, 3300 BHP (3000 HP into the generators in USA terms) this was an outstanding power to weight ratio. Before turbocharging, this power could only be obtained by using two 16 cylinder 567 engines which could not be installed in a 99 ton locomotive.
In 1962, when the production class 55s were introduced, two turbocharged 12 cylinder 567D3 engines could have been used but they’d still be too heavy.
The Deltic T18 was the only engine that could provide the power within the weight limit.
There were only ever 33 locomotives with Deltic engines. 22 class 55s and the prototype named “Deltic” and ten class 23 1100 HP units with a single 9 cylinder turboch
Anyone interested in additional information about the marine application of Deltic diesel engines might do an Internet search for “PTF-Nasty Class Boats”. The primary site contains a “technical” section with detailed discussions of the engines.
Two simple questions , if ‘M636C’ might care to answer :
Did you ever consider any of the vast difference between running conditions in Britain ( easy : low train loads , mild weather , best fuel best lub oil , best maintenance ) and Russia ( hard : high - extreme train loads , extreme weather conditions , just available fuel of dubious quality , lub oil of uncertain quality as available , used until sludged , simplest maintenance by simplest means , patch-up repairs with minimum of parts replacement preferably re-installation of re-repaired-rre-epaired-re-repaired parts if at all useable ) and inevitable consequences on incident free running hours ?
Would you mind to explain how a design with three crankshafts will yield a higher specific h.p. than a V design with a single crankshaft
on a basis of same CID , same number of cylinders and compression ratio plus same fuel , two stroke type each , to note (!!) -
and do so in spite of inevitably higher friction losses in the triple crankshaft design and more compromised gas flow ?
It amazes me how time and again there are some guys coming up with a strong believe in using a certain concept of design or a certain application to make all the difference in power output or hours of incident free running or what have you - completely ignoring the fact each and every item and component of any power producing machinery first has to be properly designed and will inevitably fail or stand to demands according to the quality designed into it - no matter what the concept or type of .
That’s what I wanted to illustrate with my theoretical (!!!) example of what I mentioned as a virtual reversial of the delta shaped delta triple crankshaft concept , namely a concept where not the cylinders are positioned between crankshafts but the one crankshaft is positioned between and in the center of surrounding cylinders : About any reasonable concept of
OK, in all seriousness, what I think the Deltic arrangement is about is Opposed Piston, which in turn means a 2-stroke Diesel.
Yes, the opposed piston has more crankshafts but it eliminates the cylinder head and those thermal losses. In the Fairbanks-Morse OP, you had two pistons per cylinder and two crankshafts. In the Deltic, you added one more crankshaft but got three times as much Opposed Piston goodness.
And yes, to replace cylinder liners you have to do a complete engine tear-down of a Deltic, and maybe your wheezing (the loco, not you) and headache-inducing BR locomotive was due for same.
So maybe the Deltic joins sleeve-valve gasoline engines, the Bristol Brabazon propeller airliner, and many other Glorious Failures to come out of the country that started the Industrial Revolution. The Deltic may have failed in the arena of maintenance requirements, but there was a scientific explanation behind pursuing that particular design that should not be dismissed out-of-hand.
I recall riding behind a Deltic in the summer of 1968 from Kings Cross to York. I didn’t notice any particularly loud engine noise or smoke, but when i got off in York, i walked toward the front to see. When it started pulling out, the roar began like no other diesel. And then the smoke. But overall, a unique and pretty successful engine in terms of years in service.
I spent all of yesterday morning in a presentation from MTU. As well as the usual local salesman, we had two engineers from Germany anxious to sell my employer 4000 series engines for new patrol boats and submarines. They were more concerned than usual because new Customs boats upon which the Navy patrol boats are expected to be based have Caterpillar 3516C engines. MTU felt, but couldn’t prove, that their engines would run longer between overhauls than the Cats. Meanwhile our people mainly complained about the MTU fuel pumps in our present Patrol boats failing and spraying fuel all over the engine room. I was trying to find out more about their new and as yet untested submarine version of the 4000.
In my previous post I indicated that the Zvezda M503 was mainly used in Soviet Navy Osa class missile boats. The 500 hour changeout time was that applied by the Soviet Navy in these missile boats. Given that the SSN-2 was a liquid fueled missile which would have required quite a lot of servicing and the cost of frequent engine changes would not have been significant compared to the costs of fielding the weapon system, it was probably considered that early replacement provided the greatest availability of the missiles.
Ok , this goes on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on …
and whenever I post ‚I’d prefer to drop it for good now‘ then that only fuels it the more and
it goes on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on and on …
it maybe comes as near to a perpetuum mobile ( running on nothing / reproducing what it consumes to re-chew and re-chew ) as can be …
not that there’s something in it , after all it’s like cranking a rusty , left-alone scrap yard piece gee however so let’s just do some mad-mechanic’s , shucks , why not .
Paul:
the opposed piston has more crankshafts but it eliminates the cylinder head and those thermal losses.<<
if it would eliminate thermal losses’ then that would mean it was superior to the ‘conventional’ layout with cylinder head .
Then consequently that would mean it had a lower specific fuel consumption .
Then tell me why aren’t ALL Diesel locomotives powered by deltic crossectional delta triple crankshaft motors ? Why on the contrary have these Deltic locos not been repeated ?
the opposed piston has more crankshafts but it eliminates the cylinder head and those thermal losses.<<
Ok , it eliminates the cylinder head and if that was a design aim per se for some reason or other then it did just that . However : what was gained by that ? Avoiding cylinder head seal ? Oh my goodness - that would be like avoiding a flat tire by using steel wheels on cars !