WesWorld

A subsim spreadsheet for a submarine similar (but not identical) to the historical Type IX U-boats. This one is a little larger, to carry an extra pair of torpedo tubes forwards and larger motors and battery banks. Surfaced range is about the same as is surfaced speed, submerged speed is a knot higher and submerged range is a good deal better (radar is a concern, where it was much less of one in the historical KM designs for the period). I'll see how close I can come with a SpringSharp later, but I needed to do this one up since the KM may order a hydrogen peroxide version of this vessel in the not too distant future and SS doesn't support that.


Date 1937 crew CREW 51
Ocean=1 Coast=0 1 10 D_body 4.1
misc crew 0 SpaceK 27.0
misc wt 4 T_sheet 1.5 6
Gun cal cm 10.5 6 Structure mass 456.7
wt gun 8.0 500
ElecHP 1500 9 misc wt 4 150
DieselHP 5200 26 wt TT 120
H2O2HP 0 0 wt mines 40
wt motors 54 20
wt diesel 75 15
L 80.0 10
Beam 7.8 wt H2O2 0 8
D 5.0 wt fuel&batts 410 6
Crush depth 250 kerb wt 1168 5
sigma 670 disp 1550 4
#TT 8 res buoyancy 25% 3
mines 40 Max Surf Spd 18.2 2
Tons Oil 210.0 Max Sub Spd 8.2 1
Tons Battery 200.0
Tons H2O2 0
Cruise speed 10 Cruise Power 861 Range 12194 s% 223%
Submerged speed 4 Submgd power 171 Range 145 d 2.75
d% 3.4%
Targets u/w speed u/w range sf spd sf range s% d% Reserve
7.6 80 17.7 8500 60% 0.6% 10%

Isn't H2O2 a tad early tech-wise? I only know of the Brit subs from the late 1950s that had H2O2 propulsion...

If i read it right, than there is no H2O2 on the sub ?

Quoted

H2O2HP 0 0 wt mines 40

Quoted

Tons H2O2 0

But i think Hrolf will give the right answer

THIS design does not have H2O2 propulsion, there's a proposal to use it on a modified version of this design.

As far as being too early, historically Walter was testing his H2O2 sub V-80 in 1940 (see here for details: http://www.uboat.net/types/walter_hist.htm ). In WW, the KM took his proposal to research H2O2 in 1934 and had the research submarine V-64 (which sank at dock in Wilhelmshavn in Q3 1936) built. A successor, V-80, is being laid down in WW Q4, 1936.

Hrolf, its usually a good idea to carefully select some of the values from subsim to use as outputs else it gets really complicated.

Date 1931
Ocean=1 Coast=0 1
Gun cal cm 10.5
ElecHP 1500
DieselHP 5200
wt fuel&batts 410
kerb wt 1168
disp 1550
res buoyancy 25%
Max Surf Spd 18.2
Max Sub Spd 8.2

L 80.0
Beam 7.8
D 5.0
Crush depth 250
sigma 670
#TT 8
mines 40
Tons Oil 210.0
Tons Battery 200.0

Cruise speed 10 Cruise Power 861 Range 12194
Submerged speed 4 Submgd power 171 Range 145

Probably true, yes. <sigh>

The 4 tons of misc. weight is intended for the subs AA weapons (1 3.7 cm single, 1 2cm twin).

Here's an equivalent SS. It's not EXACTLY the same, the two programs aren't that close to one another, but the SS light weight and the Subsim kerb weight are the same and the full load displacement is close.

Type IV, German U-boat laid down 1937

Displacement:
1,167 t light; 1,198 t standard; 1,382 t normal; 1,529 t full load

Dimensions: Length overall / water x beam x draught
264.11 ft / 262.47 ft x 25.59 ft x 16.40 ft (normal load)
80.50 m / 80.00 m x 7.80 m x 5.00 m

Armament:
1 - 4.13" / 105 mm guns in single mounts, 35.32lbs / 16.02kg shells, 1937 Model
Quick firing gun in deck mount
on centreline forward
1 - 1.46" / 37.0 mm guns in single mounts, 1.55lbs / 0.70kg shells, 1931 Model
Anti-aircraft gun in deck mount
on centreline aft
4 - 0.79" / 20.0 mm guns in single mounts, 0.24lbs / 0.11kg shells, 1936 Model
Machine guns in deck mounts
on centreline, all amidships, all raised mounts - superfiring
Weight of broadside 38 lbs / 17 kg
Shells per gun, main battery: 150
8 - 21.0" / 533 mm submerged torpedo tubes

Armour:

- Conning tower: 0.79" / 20 mm

Machinery:
Diesel Internal combustion generators plus batteries,
Electric motors, 2 shafts, 3,628 shp / 2,706 Kw = 18.20 kts
Range 12,194nm at 10.00 kts
Bunker at max displacement = 330 tons

Complement:
113 - 147

Cost:
£0.321 million / $1.285 million

Distribution of weights at normal displacement:
Armament: 5 tons, 0.3 %
Armour: 2 tons, 0.2 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 0 tons, 0.0 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 2 tons, 0.2 %
Machinery: 101 tons, 7.3 %
Hull, fittings & equipment: 790 tons, 57.2 %
Fuel, ammunition & stores: 215 tons, 15.5 %
Miscellaneous weights: 270 tons, 19.5 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
738 lbs / 335 Kg = 20.9 x 4.1 " / 105 mm shells or 0.5 torpedoes
Stability (Unstable if below 1.00): 1.08
Metacentric height 0.8 ft / 0.2 m
Roll period: 12.4 seconds
Steadiness - As gun platform (Average = 50 %): 0 %
- Recoil effect (Restricted arc if above 1.00): 0.00
Seaboat quality (Average = 1.00): 0.00

Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.439
Length to Beam Ratio: 10.26 : 1
'Natural speed' for length: 16.20 kts
Power going to wave formation at top speed: 43 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 10.00 degrees
Stern overhang: 1.64 ft / 0.50 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 0.00 ft / 0.00 m
- Forecastle (20 %): 0.00 ft / 0.00 m
- Mid (50 %): 0.00 ft / 0.00 m
- Quarterdeck (15 %): 0.00 ft / 0.00 m
- Stern: 0.00 ft / 0.00 m
- Average freeboard: 0.00 ft / 0.00 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 97.4 %
- Above water (accommodation/working, high = better): 0.0 %
Waterplane Area: 4,247 Square feet or 395 Square metres
Displacement factor (Displacement / loading): 270 %
Structure weight / hull surface area: 122 lbs/sq ft or 595 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 3.43
- Longitudinal: 1.90
- Overall: 2.20
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is extremely poor
Ship has quick, lively roll, not a steady gun platform
Caution: Lacks seaworthiness - very limited seakeeping ability

Where did you guys get this program? I don't recall.

Yes, I was just trying to Google it myself. I know it's excel but I can't find it anywhere...

Its here on the download page.

Quoted

Originally posted by Red Admiral
Its here on the download page.

Thanks. Downloaded it, going to play around with this...

Am I reading this program correctly - you fill in the light blue boxes on the second page, and it gives you results?

Anyone know where I can download excel for free?

Quoted

Originally posted by thesmilingassassin
Anyone know where I can download excel for free?

www.openoffice.org

This is open source software that is 99.9% compatible with Excel, the very odd equation may need tweaking.....

Many thanks Mac! Now to see if it works.

OpenOffice has gotten better of late: it used to fail on PlaneBuilder, the latest versions don't now.

Ok any tips on how to use this thing?

To design a sub, first, go to the Subsim tab of the workbook (the workbook has 2 tabs, 1's Real Subs, which has data on the Type VIIC, IXB, and XXI U-boats, and SubSim, which is where a new design is created). Get there by clicking on the tab at the bottom of the page.

Now, to design a sub, you just enter items in the pale blue column of the spreadsheet. Date determines a number of things: how efficient the engines are, working depth, etc. Type of sub (ocean or coastal) determines crush depth and how strongly the hull is built. Misc. Crew is for any extra crewmen you wish to add over what the program will give you, miscellaneous weight is for cargo or for additional guns (you can only enter 1 deck gun into the program), gun cal cm is for the bore size of any deck gun you want. L is length of hull, Beam is width of hull, D is depth of hull.

ElecHP is the max horsepower of the subs electric motors for operation when on battery, DieselHP is the max horsepower of the subs diesel motor for operation when on the surface on diesel, H2O2 Horsepower is the max horsepower of a hydrogen peroxide turbine for operation underwater on H2O2. What you enter here will determine max speeds, which show up in cells F46 and F47. The weights of these engines show up in F38, F39, and F41.

#TT is how many torpedo tubes the sub has (the program assumes 21"/533mm tubes), #mines is the weight of any mines or reload torpedoes carried. Tons of oil, tons of battery, tons of H2O2 are entries to enter how much fuel your boat carries, more means longer range on the approrpiate engnie, and will change the number in I50 and I51 and the shape of the graph. Cruise speed and Submerged speed are the speeds the program uses to fill in I50 and I51, vary these and watch the numbers in I50 and I51 change (it's VERY noticeable when you change the submerged speed).

The Targets line at the bottom of the sheet is a set of numbers that correspond to a Type VIIC U-boat, a good baseline for a early WWII sub. I don't worry about G54 & H54, because I don't know what they are, but the other numbers are useful.

Kerb weight (F43) is the weight of the entire sub, loaded and ready to leave port, on the surface at the dockside. Disp (F44) is the subs displacement underwater. I added a cell, as discussed in the SubSim thread, to show light weight, which is what we use in WW to determine the cost of a sub, this was the kerb weight minus fue (oil and H2O2) and mines. Res bouyancy, F45, is the amount of reserve buoyancy and ballast tankage your sub has. Low numbers mean your sub will submerge slowly and has little lifting power in the event of damage or running aground. If this goes below 0, the program will turn F45 red as a warning, but in general I wouldn't let this get below 10% or so for most combat boats, and higher is better (lets you submerge faster and gives more reserve buoyancy).