Olympics's Speed

[George Behe]

Hi, all!

It occurs to me that it might be interesting for us to compile some documentation regarding Olympic's speed and crossing times throughout her career. I suspect there are a lot of researchers here who own one or more log abstracts containing Olympic's stats for various voyages; that being the case, would anyone care to join me in posting the specific dates, direction of the voyage, crossing times, arrival times and average speeds that are listed on any Olympic log abstracts to which they have access? I feel we could compile a very useful compendium of information if we all contribute a few tidbits to the cause.

I'll dig out my own Olympic log abstracts tomorrow and will start the ball rolling.

All my best,

George

 

[Markus Philipp]

Hi George,

this is a very good idea. Think there is some thing to calculate for me. I did already this afternoon.

Markus

 

[Markus Philipp]

Hi George,

Thanks for that information about the Olympic. This is of very high interest. I am always curious, so I calculated the total mileage out of these numbers:

5 days, 13 hours and 6 minutes = 133.1 hours

21.72 knots * 133.1 h = 2890.9 miles.

This is nearly exact the distance from Queenstown Daunt Rock to New York Ambrose.
(I found 2889 miles, but 2 miles more or less don't matter).

This confirms my assumption that the passage times are taken between Daunt Rock and Ambrose (presumed the ships really depart from there).

Further I found that Olympic passed the Daunt Rock at 2.02 pm on this journey:

New York, Tuesday, 10.08 pm, back 5 days 13 hours 6 min = NY, Thursday, 9:02 am = Queenstown, 2:02 pm.

In the US-enquiry I found a memorandum of Pitman about the daily mileages of Titanic. This tells that Titanic passed the Daunt Rock at 2.20 am. So I know definitely that the first days 484 miles count from there.

All this makes a lot of sense. Do you have some information about the daily runs as well ? I would be very happy about this.


Hi Mark,

Your propeller table is very interesting, because I made a similar thing for the Titanic. My results are slightly different from yours, so I would like to discuss this. One question on top: Did you bear in mind the gulf stream ?
This will result in less speed westbound and more speed eastbound with the same revolutions.

I want to line out how I found my "speed-revolution-key":
In a book about ship building I found diagrams of a screw. From these I saw that the speed increases linearly with the revolutions, at least approximately in a small range. Now I had to calculate the daily speed first. A small estimated value for the current is added to get the speed through the water. (The values for time are explained at the end).


day . . . mileage . time . . . speed/ground . . current . . speed/water
________________________________________________________________________
1st . . . .484 . . . 23.6 h . . 20.60 . . . . . . . . . 0.2 . . . . 20.8
2nd . . . 519 . . . 24.7 h . . 21.01 . . . . . . . . . 0.4 . . . . 21.4
3rd . . . .546 . . . 24.7 h . . 22.10 . . . . . . . . . 0.4 . . . . 22.5

The speed through the water should increase with the revolutions as given by Ismay. So I build the ratio of speed and revolutions:

Day speed/water revolutions q=speed/rpm
_____________________________________________
1 . . 20.8 . . . . . . . 70 . . . . . 0.297
2 . . 21.4 . . . . . . . 72 . . . . . 0.297
3 . . 22.5 . . . . . . . 75 . . . . . 0.300

the mean value for q: (0.297 + 0.297 + 0.300)/3 = 0.298
Using the q = 0.298 I find these speeds through the water:

R.P.M. . Knots
70 . . . . . 20.86
72 . . . . . 21.45
75 . . . . . 22.35
78 . . . . . 23.24
79 . . . . . 23.54
80 . . . . . 23.84


R.P.M. Knots (your table for compare)
70 . . . 20.50
72 . . . 21.00
75 . . . 22.08
78 . . . 22.68
79 . . . 22.82
80 . . . 22.96
81 . . . 23.2+
82 . . . 23.35+

I assume an average gulf stream of 0.5 knots. Travelling in either direction with 75 rpm I would expect westbound 21.8 knots over ground which meets very well what George posted about Olympics second journey. Eastbound I would expect 22.8 knots over ground.

To achieve 22.8 knots westbound I need 23.3 knots through the water according to 78 rpm.

One question to your post:
You wrote: "Now I know the fastest crossing was Eastbound, assuming this was the approximate same mileage as Olympic's Eastbound 22.48 knot crossing in 1911 of 5 days 14 hours 32 minutes from New York to Plymouth, the 5 day 12 hour 39 minute fastest crossing would be at a speed of 22.82 knots, …"

What was the destination of Olympics Eastbound crossing 1911: Was it QT or Plymouth ?
The mileage from QT to Ambrose westbound is 2889 miles. Eastbound it is some miles more, maybe 5..10 miles.

The mileage to Plymouth is considerable more. I looked it up in my Blue-Riband book and found 3084 miles. (I will calculate this some time)

This makes a speed of 3084 miles / 132.6 h = 23.26 knots over ground or 22.76 knots through the water because of eastbound journey. Using my "revolution key" I get 22.78 knots / 0.298 = 76.4 revolutions.

So far my salad of knots and miles.


This are the details about the time to calculate the daily speed.
Time first day:
Daunt Rock 2.20 pm till noon Friday = 21 h 40 min. Unfortunately Pitmans figure seems odd concerning the time for the first day: He divides 484 miles by 22.6 hours and results in 21.14 knots. My calculator says 21.41 knots then.

So I had to reconstruct the time setting for the first day:

1 . . 1 h 59 min (5 h - 44 min - 44 min - 47 min - 46 min)
2 . . 44 min (Pitman)
3 . . 44 min (Pitman)
4 . . 47 min (Hitchens)
5 . . 46 min (Rostron, telegram)

The total time from 2.20 pm till Friday noon is
21 h 40 min + 1 h 59 min = 23 h 39 min = 23.55 h



All my best

Markus

 

[George Behe]

Markus wrote:

>This is nearly exact the distance from Queenstown >Daunt Rock to New York Ambrose.
>(I found 2889 miles, but 2 miles more or less >don't matter).

Hi, Markus!

Thank you for your calculations, and you're right -- the distance was measured to the Ambrose Channel Light Vessel.

I haven't had time to dig out my other Olympic log abstracts. I'll do so as soon as I can.

All my best,

George

 

[Mark Chirnside]

Markus,

(Sorry for my spelling, I am exhausted typing and putting capitals in.)

Your maths is far better than mine, I confess.

Regarding my table, sorry I didn’t make it clear before. It’s so tricky to get exact figures, what with the various currents and many sources not distinguishing between ‘through the water’ and ‘over ground.’ In my table, I only calculated very rough values for ‘over the ground,’ which is usually given in many books; these are not specifically for the atlantic. As your table is for through the water, that makes a difference; otherwise I am pleased that they are quite similar.

For example: for my 74 r.p.m. figure (one not quoted here) Edward Wilding said Olympic was run at 74 r.p.m., getting roughly 21.50 knots; not in atlantic, but somewhere sheltered, as it were. ‘over ground,’ I think that was.
For 79 r.p.m. figure: Duncan Haws’ book ‘Merchant fleets’ that deals with the white star, he lists ‘22.82 kts by builder’ for the Olympic. Over ground, I presume.
I used various sources for the whole table. Some from Titanic…some from British enquiry…some by my calculation…

I am not really that technically-minded and so do not go into exact details in my upcoming book.

If my table was changed to ‘speed through water’ going up to 81 r.p.m., the highest figure confirmed for Olympic, which was briefly got on her maiden voyage, our tables would be little differing. At least they weren’t embarrassingly totally different!

The 1911 22.48 knot crossing was 134.5 hour new york to Plymouth; I don’t have the mileage.

George;

BTW, some Olympic crossing times for our research. Mainly taken from ‘Sea Classics,’ February 1956.

(‘Westbound 3’ may be number 4 or other, but was during first year.)

Westbound 1: 136.6 hr…21.17 kt
Eastbound 1: (?)………22.32 kt

Westbound 2: 133.1hr…21.72 kt
Eastbound 2: 134.5 hr…22.48 kt

Westbound 3: 127.5 hr…21.8 kt (rough)

Mid-1920 Eastbound: 133.1 hour…22.53 kt.

Cheers,

Mark.

 

[David G. Brown]

Not to throw a monkey wrench into the works, but do we know that Titanic's propellers were, in fact, the same pitch as Olympic's props?

It is a stunt among ferry boat operators to up the pitch a bit on an early run...load the boat with minimum fuel...keep the passenger load down...and make a high-speed run for publicity. The props are then removed and re-pitched for normal operation.

Not that I'm suggesting that Ismay would have been up to such shenannigans...

-- David G. Brown

 

[George Behe]

Dave wrote:

>Not that I'm suggesting that Ismay would have >been up to such shenannigans...

Hi, Dave!

Somewhere around here I have a pre-sinking article which mentioned that Olympic had been fitted with 'improved' screws sometime between her maiden voyage and 1912 and that the Titanic would presumably be fitted with similar screws (which would probably improve her maiden voyage performance over that of her older sister.)

All my best,

George

 

[George Behe]

Hi, Markus!

I've found a couple of additional Olympic log abstracts that I'd stashed away in a box of goodies.

Sept. 11, 1929: Olympic departed from the Cherbourg breakwater at 8 p.m. GMT. Arrived at the Ambrose light vessel at 1:16 p.m. EST on Sept. 17, 1929. Total distance covered 3,095 miles. Time -- 5 days 22 hours 15 minutes. Average speed 21.76 knots.

August 2, 1930: Olympic departed from the Ambrose Channel light vessel at 1:20 a.m. EST. Arrived at the Cherbourg breakwater at 4:53 a.m. GMT on August 8, 1930. Total distance covered 3,200 miles. Time -- 5 days, 22 hours 33 minutes. Average speed 22.45 knots.

All my best,

George

 

[George Behe]

Hi, Mark!

Thanks very much for the additional information. Great stuff!

All my best,

George

 

[Mark Chirnside]

Everybody; a challenge for mathematically superhuman rivet counters! (About the last trip of Olympic to Jarrow.)

‘I could have understood the necessity (of scrapping the Olympic) if the “Old Lady” had lost her efficiency, but the engines are as sound as they ever were,’ Chief Engineer C. W. McKimm said, who had been on the Olympic since 1911 as a more junior engineer.

He said the performance on the final trip was great. ‘Never, at any time were the engines full-out.’

Now, the challenge; what was the average speed, over the ground?

Left Southampton at 16.30 Friday 11th October 1935. (Presumably this counts as the 'mouth' of Southampton water.)
Arrived ‘off the Tyne piers’ — at the mouth of the river Tyne, I think — 22.00 Saturday 12th October 1935.

Total approximate journey time as far as I can make-out: 29.5 hours.
Total distance: (I do not know.)

Thus: if the distance — or at least an approximation — can be found-out, so can the average speed. What was it? I do not know and wonder if anyone can help solve the challenge?

Mark.

 

[Markus Philipp]

Hi Mark, i will work out the distance. But i have to define a shipping lane around England without any information whether Olympic used that way. So i can give the shortest possible distance, maybe it was 10% more then in reality.

Markus

 

[Markus Philipp]

Hi Mark,


I tried to summarize the mileage from Southampton to New Castle. The points I selected are about 10..15 miles offshore the places I have given.

1. Mouth of Sotn Water . . . . . . 50°49'N, 1°17 W . . --
2. Selsey Bill . . . . . . . . . . . . . 50°36'N, 0°47'W . . 23 miles
3. Eastburn / Beachey Head . . . 50°36'N, 0°15'W . . 31 miles
4. Dungeness . . . . . . . . . . . . . 50°48'N, 0°15'E . . 39 miles
5. Dover . . . . . . . . . . . . . . . . . 51°05'N, 1°53'E . . 32 miles
6. Great Yarmouth. . . . . . . . . . 52°40'N, 1°55'E . . 97 miles
7. East of New Castle. . . . . . . . 55°00'N, 1°00'W . .174 miles
8. Tynemouth . . . . . . . . . . . . . 55°00'N, 1°24'W . . 14 miles
---------------------------------------------------------------------------------
Total: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .405 miles


The average speed with 405 miles in 29.5 hours is 13.7 knots. Now we don't know whether she steamed with constant speed all the time.
Lets say she made the first 10 miles with 5 knots and the last one as well, then we have 25.5 hours for the remaining 385 miles. 385 miles in 25,5 hours = 15.1 knots.
This is the range i would estimate for the last voyage.

Markus

 

[Mark Chirnside]

Markus,

Thanks very much for the distance figures and speeds; it was strange in that the information I saw - from a Newspaper article, quoting the chief engineer - made it seem that the speed would be much higher, and it was a surprise to see the low figures. Reporter's Hyperbole, perhaps. Still, Olympic arrived several hours early.

Cheers,

Mark.

 

[Markus Philipp]

Hi Mark,

Positions 3, 4 and 5 were a bit queer by typing errors. I corrected them. Maybe somebody wants to sail this course. The total distanced remains unchanged.

1. Mouth of Sotn Water . . . . . . . 50°49' N, 1°17' W . . --
2. Selsey Bill . . . . . . . . . . . . . . 50°36' N, 0°47' W . . 23 miles
3. Eastburn / Beachey Head . . . 50°36' N, 0°15' E . . 39 miles
4. Dungeness . . . . . . . . . . . . . 50°48' N, 1°00' E . . 31 miles
5. Dover . . . . . . . . . . . . . . . . . 51°05' N, 1°35' E . . 28 miles
6. Great Yarmouth. . . . . . . . . . 52°40' N, 1°55' E . . 96 miles
7. East of Newcastle. . . . . . . . 55°00' N, 1°00' W . .174 miles
8. Tynemouth . . . . . . . . . . . . . 55°00' N, 1°24' W . . 14 miles
---------------------------------------------------------------------------------
Total: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 405 miles

Markus

 

[Mark Chirnside]

Everyone,

Another interesting piece of information: in 1932, the Board of Trade were informed that Olympic's speed would be limited to 21 knots to reduce stresses on the hull, but at the same time when she got into New York early in 1933, it was announced that the 'new engines' (actually, just reconditioned engines) were better than new, able to give 23 knots, which would be realistic as a maximum, but not for a service speed, especially because of the 21-knot limitation.

Yet according to John Maxtone-Graham, the crossing times remained consistant with the 'old engines' after 1933; this is strange again because Olympic was still frequently averaging in excess off 22 knots, certainly in the early thirties, perhaps after 1933.

Mark.