WesWorld

Hello guys, decided to start a new thread....

This one is about the famous Cunard speed queen Mauretenia (1907-1935). She was the fastest Atlantic liner for nearly a quarter-century (22 years) and held the coveted Blue Riband record at 26.06 kts westbound.

Here is my question: What would be necessary for Muaretania to match the SS United States, as far as speed is concerned? I calculated that she would need at least 172,000 SHP to be able to average 38 knots over the Atlantic. Is this over-reaching myself? Would it be possible to pack this much horsepower into geared turbines, and if so, how would i fit it into 'Maury'?

Any help would be appreciated...

It's actually not a factor of pure horsepower, though that will play into it; but a question of hull form. If you design a ship for 26 knots, then your hull form is based on that speed. If you design for 38 knots, then the same thing happens. Upping the speed will invoke diminishing returns, requiring disproportionately higher amounts of power to achieve speed increases.

I don't recall of any cases where 20ish knot ships were ever refitted to be 30+ knot ships. At least, not unless they were specifically designed to be later upengined.

Quoted

Originally posted by Brockpaine
I don't recall of any cases where 20ish knot ships were ever refitted to be 30+ knot ships. At least, not unless they were specifically designed to be later upengined.

The Italian battleships did go from 21 to 28 knots, which is comparable. But such a project was insanely expensive and politically motivated (the Italians weren't /allowed/ to build something new). I don't view it as a practical or reasonable idea for a liner.

This is further compounded by the fact Mauretania had been scrapped 20 or so years before the United States was even laid down.

Cunard's goal of regaining the Blue Riband would be pursued the same way as historical; Build a bigger, better ship.

thanks guys.

So the main idea you guys are advocating is that designing a ship for 38 knots is better than refitting an older ship for the same speed.

For example: my RMS Canada is better designed for 38 knots than refitting RMS Mauretania for the same speed.

Quoted

Originally posted by RMSCANADA
thanks guys.

So the main idea you guys are advocating is that designing a ship for 38 knots is better than refitting an older ship for the same speed.

Yes. It will not only allow the hull to be designed for more speed, but it permits new design theories to be applied, allowing for a better ship overall. Sometimes saying "They don't build them like they used to" is a good thing, after all.

Still, I think once you pass the thirty-knot limit with a liner, it's not really worth the benefits. It's time to get an airplane if you need that.

Hi guys, i'm back.

This time i wanted to ask you guys whether this design could work. Positive feedback would be greatly appreciated. I designed her to be the Canadian contender for the Blue Riband.

Here are some my questions:
1. Is this feasible?
2. Could she maintain 35 knots for a whole voyage?
3. Is the passenger capacity realistic, as far as modern standards go?
4. Can anybody draw me a rough rendering of what she might look like? 'Cause everytime i draw my speedster, it looks too much like the american liner United States.

RMS CANADA, Canadian Blue Riband Contender

Gross Tonnage: 51,492 gross tons (approx)

Displacement: 34,970 t light; 35,802 t standard; 41,600 t normal; 46,238 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(992.00 ft / 950.05 ft) x 100.00 ft x (30.00 ft / 32.64 ft)
(302.36 m / 289.58 m) x 30.48 m x (9.14 m / 9.95 m)

Machinery:
• Oil fired boilers, steam turbines
• Geared drive, 4 shafts, 242,430 shp / 248,000 bhp = 38 knots
• Range 4,000 nm @ 38 knots or equivalent 10,000 nm @ 35 knots
• Bunker at normal / max displacement = 5,798 tons / 10,436 tons (fuel oil)

Complement: 1,456 - 1,893 (designed for 1,000)

Cost: £15.917 million / $63.669 million

Distribution of weights at normal displacement:
• Machinery: 5,800 tons, 13.9 %
• Hull, Fittings & Equipment: 15,721 tons, 37.8 %
• Fuel & Stores: 6,630 tons, 15.9 %
• Miscellaneous Weights: 13,450 tons, 32.3 %
o Hull below water: 4,800 tons
o Hull above water: 3,600 tons
o On freeboard deck: 4,800 tons
o Above deck: 250 tons
Overall Survivability and Seakeeping Ability:
• Survivability (Non-critical penetrating hits needed to sink ship):
o 90,379 lbs / 40,995 kg = 836.8 x 6 " / 152 mm shells or 5.1 torpedoes
• Stability (Unstable if below 1.00): 1.14
• Metacentric height 6.4 ft / 1.9 m
• Roll Period: 16.7 seconds
• Steadiness (Average = 50 %): 88 %
• Seaboat Quality (Average = 1.00): 2.00

Hull Form Characteristics:
• Hull has a flush deck, a normal bow and a round stern
• Block Coefficient (normal/deep): 0.511 / 0.522
• Length to Beam Ratio: 9.50 : 1
• Hull Speed: 41.30 kts
• Power going to wave formation at top speed: 50 %
• Trim (Max stability = 0, Max steadiness = 100): 44
• Bow Angle (Positive = bow angles forward): 26.00 degrees
• Stern Overhang: 20.00 ft / 6.10 m
• Freeboard Breakdown
Fore end, Aft end
- Forecastle: 20.00 %, 45.00 ft / 13.72 m, 42.00 ft / 12.80 m
- Forward deck: 30.00 %, 42.00 ft / 12.80 m, 42.00 ft / 12.80 m
- Aft deck: 35.00 %, 42.00 ft / 12.80 m, 42.00 ft / 12.80 m
- Quarter deck: 15.00 %, 42.00 ft / 12.80 m, 42.00 ft / 12.80 m
- Average freeboard: 42.24 ft / 12.87 m

Ship Space, Strength and Comments:
• Space - Hull below water (magazines/engines, low = better): 68.1 %
- Above water (accommodation/working, high = better): 338.3 %
• Waterplane Area: 61,573 square feet or 5,720 square meters
• Displacement Factor (displacement / loading): 166 %
• Structure weight / hull surface area: 135 lbs/sq ft or 661 kg/sq meter
• Hull strength (Relative):
o Cross-sectional: 0.90
o Longitudinal: 2.48
o Overall: 1.00
• She has excellent machinery, storage, compartmentation space
• She has Excellent accommodation and workspace room
• She has a slow, easy roll, a good, steady ocean liner
• She is an excellent seaboat, comfortable, rides out heavy weather easily

Passenger Count
Allowing a 1,200 ton capacity for passenger baggage and express cargo leaves 12,250 tons for passengers.

First Class Passengers (16 tons/passenger): 60% = 7,350 tons = 460 passengers
Second Class Passenger (4 tons/passenger): 40% = 4,900 tons = 1,224 passengers
Total Passenger Capacity = 1,684 passengers

Passenger Space Ratio (GRT/guest) = 30.6 tons/guest

Quoted

Originally posted by RMSCANADA
Here are some my questions:
1. Is this feasible?
2. Could she maintain 35 knots for a whole voyage?
3. Is the passenger capacity realistic, as far as modern standards go?
4. Can anybody draw me a rough rendering of what she might look like? 'Cause everytime i draw my speedster, it looks too much like the american liner United States.

1) That depends on several factors; When is it being laid down? By whom? If by Cunard or another line, why do the historical liners need replacing? If by a line that didn't historically compete in the transatlantic trade, why are they doing so now?
2) This also depends on several factors, usually weather related. For a general answer, however, if the ship is designed to do so, it likely can
3) Define "modern"; is this ship competing with the United States in the 1950s (as previous posts indicated), or with the Queen Mary II and large cruise liners today?
4) This, also, depends on several factors, most notably when and where the ship is being built, and if there's any goals in the design process (for example, the Queen Mary II was designed to have several cosmetic 'call-backs' to previous Cunard liners that otherwise wouldn't have appeared).

Here are my answers to your anwers:


That depends on several factors; When is it being laid down? By whom? If by Cunard or another line, why do the historical liners need replacing? If by a line that didn't historically compete in the transatlantic trade, why are they doing so now?
I designed my RMS Canada to be laid down in this century (when, I don't know). I want her to be operated either by Canadian Pacific Steamships, Cunard Line, or one of the other surviving transatlantic companies.

Could she maintain 35 knots for a whole voyage? I designed her to, so i think she could, i mean she has enough fuel for 10,000 miles at that speed--the same as the historical SS United States.

Define "modern"; is this ship competing with the United States in the 1950s (as previous posts indicated), or with the Queen Mary II and large cruise liners today?
Again, I designed her to compete in the modern transatlantic trade (ie with QM2 and other liners) so balconies, casinos, and other modern amenities are definitely needed. Hopefully i can fit all these modern innovations and still keep the traditional graceful profile of the past ocean liners.

Can anybody draw me a rough rendering of what she might look like? 'Cause everytime i draw my speedster, it looks too much like the american liner United States.
Here, i want her to be Canadian themed, obviously red and white have to be on the funnels (canadian national flag).

I do understand that design goals might influence the look of the ship. I want her to be up to modern standards--i.e. fireproofing, subdivision, stability, passenger safety, namely lifeboats (i hope those pesky SOLAS officials will let me put the lifeboats where i want to put them...grrr) but also retain the classic liner look. I am sure that many designs turned out differently than planned, due in part to modern safety and operating standards forced a chanhe in redesign.

Some of the looks i was trying out for the ship included a SS US type hull with Titanic's enclosed promenade above and the SS Bremen (1929) curved bridge front. The funnels, i was looking into something like the Italian SS Rex or SS Roma. I wanted to keep tke sleek look of the United States in my design. Obviously, you can see i am drawing on lots of ocean liner knowledge here, but i don't know if all these different looks would belnd well together. What do you think? If you can, may you sketch her for me. That would be very greatful of you.