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Titanic's propellers

Discussion in 'Engine Room Engines & Propulsion Systems' started by Ken Marschall, Dec 9, 2002.

  1. Ken Marschall

    Ken Marschall Member

    It's been a long time since I posted something and am not sure if I'm doing this correctly, or in the right catagory/thread. But here goes -- to the "tech/design/construction" message board:

    I feel like an idiot having to send this. After looking through many books and failing to find what I thought would be a simple, common statistic for Titanic's wing propellers, I tried ET. I thought the site might have a detailed "specifications" list for the ship with every bit of structural trivia imaginable. But not yet, it seems.

    I'm trying to find the weight of Titanic's propellers. Their dimensions are published in many sources, but the weights are hard to come by, for some reason. I know I've seen their weights published somewhere, more than once, but I'll be
    darned if I can put my fingers on it now. Terribly frustrating. (I'm assisting Don Lynch in writing some captions for the companion book to the large-format 3D film "Ghosts of the Abyss," due out in April.)

    Can someone prod this addled brain toward a source for this info? If simply replying with the weights, will you please provide source?

    Many thanks!

    (Now watch-- the info is probably in one of the books I worked on!)

    Ken Marschall
  2. Ken,

    The numbers that are stuck in my head are:

    Wing: 38 tons
    Centre: 22 tons

    Dang if I can remember the source, though. I'll check through my library, or you can. Too bad Bill isn't here.

  3. Would there be some mention of the dimensions in the Shipbuilders publication?


    Tarn Stephanos

    welcome back Ken!-
  4. Unfortunately, the Shipbuilder doesn't give the weights. It does give the diameters which was 23ft 6in for the wing propellors and 16ft 6in for the centre propellor. The composition was bronze for the blades and cast steel for the bosses of the wing propellors and mangenese-bronze for the centre.

    Curiously, I couldn't find the information on weights in my copy of what's known as Thomas Andrews Notebook either.

    If I do find anything, I'll let you know.
  5. James Smith

    James Smith Member

  6. Ken. My husband and I were able to finally locate it in a book. It does not give specific sources, except that the text research was by Greg Curtis, but it indeed was a book Don Lynch was a historical consultant on, and you did the paintings. smile.gif
    The book is called 882 1/2 Amazing Answers to your questions about the Titanic. by Hugh Brewster and Laurie Coulter. it is a Scolastic Inc /Madison Press book. Copyright 1998
    the answer is listed on page #13.
    Question 58, which says:
    The wing propellers were 23.5 feet (7 m) and weighed 38 tons (34 t).
    Question 59 states: Center propeller was 16.5 feet (5 m) and weighed 22 tons (20 t).
  7. Hi!

    I can give one further source for 38 and 22 tons -- the Belfast Press in 1910-11. If I recall, the Belfast News Letter reported it more than once. They got other details mostly right, though not all.

    Likewise, I feel that I have seen this source somewhere else as well but I cannot remember.


    Best regards,

  8. Ken Marschall

    Ken Marschall Member

    My gosh, I thought I might get an answer from someone soon but certainly did not expect so much help from all you fine people! Many thanks to all wrote wrote regarding the specs for the propellers. I really appreciate it.

    Colleen-- The book "882 1/2 Answers..." was one of the sources I checked before resorting to ET, and could find no weight info, or so I thought. I must be blind. Too many late hours working on this project.... Like right now--it's four in the morning.

    Again, thanks to you all. What an incredible resource this site is.

    Best wishes,

  9. I think I started a thread on this a while back concerning the weights and it was never finished off.
  10. Hi Ken!

    Yep, ET is incredible. It's nice to see you here.

    Hi Stephen!

    Your thread *was* finished off -- or nearly, anyway. I told you the 38 and 22 ton figures, perhaps my sources (some of which i forgot) are in that thread? What was it called? We could try to find it.

    Best regards,

  11. Late hours Ken? You might as well join the Navy! If you like burning the candle at both ends and in the middle, you'll love standing midwatches!

    I went through some of my own books last night and I was surprised that even Michael McCaughan's Birth of Titanic didn't have that information. Looks like I'll have to order that book that Colleen used.
  12. Dan Cherry

    Dan Cherry Active Member

    for what it's worth, I have a 1914 book "The Book of Wonders", showing the Britannic's propeller during the construction phase (this book is also in the THS collection, according to Ed Kamuda). It corroborates the above figures of 38 tons and 22 tons for Britannic and Olympic's props.

  13. Hi!

    Dan brings up a good point: "It corroborates the above figures of 38 tons and 22 tons for Britannic and Olympic's props."

    Although we have these figures again, which is excellent since sources often contradict each other, how will we ever know if they are accurate? Olympic, Titanic and Britannic all had propeller pitch/diametre configurations that differed slightly, and at different times (certainly for Olympic) -- so how could we calculate how much this would have effected the weights?

    Best regards,

  14. Bill Sauder

    Bill Sauder Member


    Here are the particulars for the Olympic's propellers taken from Harland and Wolff documents. They differ from the numbers quoted earlier in this thread, but have the advantage of being taken from working documents, not the popular press or secondary sources.

    I'm sorry for such a short post but I have 3 major business deadlines this week.

    Bill Sauder

    Early Olympic Propellers:

    Wing Screw:

    bosses 14ton 16cwt 1qtr 0lb
    blades 8ton 3cwt 0qtr 0lb
    with nut and cone: 38ton 7cwt 2qtr 3lb

    Turbine screw: 16ton 9cwt 2qtr 0lb
  15. Thanks Bill for your post. May I ask a silly question? (Doesn't he always you ask? wink.gif )

    The wing propeller figures fit with the previous sources, albeit secondary. No doubt this is good.

    On the turbine propellers it says over 16 tons. There's no mention of the blades. Could it be that a blade weighing, say, six tons (vs. eight tons on the larger wing propellers), is missing? Olympic had three blades on her central propeller from 1913 to 1919, instead of the four of 1911-13 and 1919-1935 (apparently without changes).

    I know it says 'Early Olympic,' but Olympic in 1913 would seem to fit that term as well as the 1911 ship. Also many 1913 changes appear in 1911 documents -- but sometimes are not clearly marked. But my maths is hopeless so my attempt at explaining the 'central propeller figure difference' has probably torpedoed itself.

    Best regards,

  16. Mark,

    That figure for the center propeller would not have included a seperate weight for the blades as this screw was cast in one piece. As you know, the wing propellers were of the "built-up" type, so the weights of the boss and blades were given seperately. Of course, Bill's reply does raise another question: is that weight for the center screw for the propeller alone, or does it include the nut and cone?

    Now regarding the wieght of the three-bladed screw of 1913 - 1919, even though this screw had fewer blades, it could very possibly have weighed more than the original four-bladed screw, since both the figures for it's diameter and the blade surface area are greater.


    Scott Andrews
  17. Hi Scott,

    Thanks for your reply. I was forgetting that the blade was cast as 'one' rather than having blades attached as with the wings. My one question really does centre around the middle propeller -- as you say, it raises the question whether or not the weight includes the nut and cone. I've no idea of their weight, but there must be six tons somewhere to make up the difference between 16 and 22 tons. Otherwise, where did 22 tons come from, considering that the 38 tons was correct?

    One question: "regarding the wieght of the three-bladed screw of 1913 - 1919, even though this screw had fewer blades, it could very possibly have weighed more than the original four-bladed screw, since both the figures for it's diameter and the blade surface area are greater."

    Here's a point: how do we know Olympic's centre screw specification was not changed between the 1910 source and Bill's later Olympic documents? Could 22 tons have been accurate for the original design and then 16 tons for the 'end' 1911 fitting? I find it incredible that the screw was changed in 1913, then reverted to the original in 1919, if not before. But we know that they were always tinkering, no to mention Andrews' 1911 observations. I've never bothered to research if Olympic's propeller specifications were ever changed pre-launch, or post-launch/pre-May 1911.

    Best regards,

  18. Bill Sauder

    Bill Sauder Member

    The propeller data was taken from undated longhand material wedged onto a blank page of an Olympic engineer's notebook. The book is nominally dated 1911, but dated additions continue right up to the last years. It's difficult to state the year of the figures I mention, other than they were "early," i.e., pre Oct 31 when the steel bossings for the wing screw were replaced with larger 16t 5c 1q 0L units.

    The 16t (1931) and 14t (1911) boss weights in both cases include the studs and nuts. No mention explicitly made for the fairing cone.

    The weight of the 4 blade screw (16 9 2 0) is confirmed by an earlier, approximate weight earlier in the manuscript (17t). Again, no mention of the fairing cone. The exact entry reads:

    Weight of 4 Bladed Turbine Propeller 16-9-2-0
    Weight of 3 Bladed Turbine Propeller 17-13-2-0

    My guess is that neither the outboard nor center figure includes the fairing cone since the weight of the individual components listed in my first post add up to the final weight, also listed in that post.

    Also, the figures are given in the context of safe hoisting. Since the propeller cone can't be lifted with the fairing cone in place, I don't think it's part of the quoted weight.
  19. Hi Bill,

    I know you're very busy, but when you next get a chance could you please check those figures for the wing screws again? I've added these figures up several times and they're not making sense. By these numbers, one boss and three blades equal 87,948 lbs, or 39.2625 tons. This assumes 1 ton = 2240 lbs; 1 cwt = 112 lbs; and 1 qtr = 28 lbs.


    Scott Andrews
  20. Bill Sauder

    Bill Sauder Member

    Will do Scott. Tonight or tomorrow.