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32 GUN FRIGATE

HMS SOUTHAMPTON

STABILITY ANALYSIS

R. Braithwaite

Issue 01

Oct 2009

HMS Southampton Stability Analysis

R.Braithwaite Issue 01

Contents 1 Introduction ........................................................................................................ 3

2 Stability Model ................................................................................................... 4 3 Downflooding Points .......................................................................................... 7

4 Hydrostatic Tables ............................................................................................. 8 5 KN Tables ........................................................................................................ 10

6 Load Conditions ............................................................................................... 12 7 Weight Estimate ............................................................................................... 13

7.1 Hull ........................................................................................................... 14 7.2 Armament ................................................................................................. 15

7.3 Top Hamper .............................................................................................. 16 7.4 Ground Tackle .......................................................................................... 17

7.5 Boats ......................................................................................................... 17 7.6 Stowage .................................................................................................... 17

7.7 Men and Effects ........................................................................................ 18 7.8 Ballast ....................................................................................................... 18

8 Stability Criteria ............................................................................................... 19 9 Results ............................................................................................................. 22

9.1 Departure Condition (Foreign Service 6 months) ....................................... 23 9.2 Arrival Condition ...................................................................................... 24

9.3 Design Condition ...................................................................................... 26 10 Discussion .................................................................................................... 28

References ............................................................................................................... 30 Appendix 1 Hydrostatic Tables................................................................................ 31

Appendix 2 – KN Tables ......................................................................................... 38 Appendix 3 Weight Estimate ................................................................................... 42



1 Introduction

This report relates to a reconstruction of the 32 gun frigate HMS Southampton (built

in 1757) described in Ref.9.

Data used for this reconstruction and the reconstructed drawings were used to analyse

the vessels stability.

A critical part of the study involved reconstructing a weight estimate for the vessel.

Whilst contemporary data (together with hydrostatics from the stability model)

enables a good estimate to be made of total displacement and longitudinal center of

gravity (LCG), the vertical center of gravity (VCG) had to be derived by detailed

calculation which included a number of assumptions (discussed in the report). The

VCG is critical in determining the stability of any floating vessel, so the reliability of

this stability analysis is highly dependent on the validity of these assumptions.

The results of the analysis are compared with current UK stability criteria for sail

training vessels and some of the implications on the operation of the vessel are

discussed.

Data generated from this analysis has been used in a velocity prediction study (Ref.

10).



2 Stability Model

A 3D surface model was created using Maxsurf Software. This was created by fitting

a hull surface to imported images of the hull moulded sections, waterlines and

buttock lines.

Figure 1 and Figure 2 show views of the Maxsurf model surfaces with sections,

waterlines and buttocks positioned as shown in the design draught reconstruction

(Ref. 9).

Stability Analysis was conducted in Hydromax software. Figure 3 shows the sections

interpolated by this software from the Maxsurf Surface model (with the 3“ skin

thickness added).

A free flood area was added to represent the space between the upper deck and the

quaterdeck/forecastle (shaded area in Figure 4). This was assigned a permeability of

95% (in line with MCA/MoD recommendation for permeability of accommodation

spaces Ref. 3).

The origin is taken at the underside of keel at the aft perpendicular. The x axis is

taken as positive forwards. The y axis positive to port and the z axis positive upwards.

All units are metric unless otherwise stated.

The Aft draught marks are at the aft perpendicular and the forward draught marks are

at the forward perpendicular (x= 37.897 m)

Density of water taken at 1.0252 tonnes/m3



Figure 1 HMS Southampton Maxsurf Model Stern

Figure 2 HMS Southampton Maxsurf Model Bow



Figure 3 Hydromax Sections

Figure 4 Midship Section Showing Extent of Freeflood Space



3 Downflooding Points

Down flooding points were positioned at the corners of the centerline hatch at

midships. A downflood point is defined as an opening which, when immersed will

cause progressive flooding of the vessel.

A warning point was also set at the lower corner of the midships gun port. It is

obviously desirable not to immerse the gunports (particularly when these are open).

However, these openings will not cause downflooding if immersed and any water

taken on board should make its way back overboard through the upper deck scuppers.

X (m) Y (m) Z (m)

Centerline Hatch 20.700 0.760 6.600

Aft Hatch Corner 7.363 0.760 7.045

Forward Hatch Corner 26.959 0.760 6.979

Midship Gunport sill 20.990 4.496 7.032

Table 1 Downflood/Warning points

Figure 5 Key Points

Midship

Gunport

Downflood points



4 Hydrostatic Tables

Hydrostatic tables derived from the Maxsurf model are presented in Appendix 1.

These are tabulated for a mean draughts ranging from 4 to 5 meters and trim of 0m to

0.5m by the stern.

The displacement (and any other hydrostatic property) can be calculated for from any

set of draught mark readings as follows:

1. Calculate the draught at amidships as being the mean of the draught at the AP

and that at the FP.

2. Calculate the trim as the difference between the draught at the AP and that at

the FP

3. Interpolate for the calculated mean draught from the hydrostatic tables with a

trim both greater and lower than the calculated trim interpolated for the

calculated midship draught.

4. Interpolate between these values for the calculated trim to find the

displacement at the required mean draught and trim.

If the vertical center of gravity (KG) is known the initial stability of the vessel can be

calculated.

Initial stability is measured by a quantity known as the metacentic height (GMT).

This can be calculated from the value KMT interpolated from the hydrostatic tables

(as above) and the vertical center of gravity as follows:

GMT= KMT-KG

If GMT is greater than zero the vessel is stable, if it is less than zero the vessel is

unstable.

Other hydrostatic parameters presented in the results section area as follows:

CB: Block Coefficient: An indication of the fullness of the hull and equal to

the Displacement Volume divided by Waterline length x beam x

draught.

CP: Prismatic Coefficient: an indication of the distribution of the volume of

the underwater hull . A low Cp indicates a full midship section with

fine ends. It is evaluated by dividing the displacement volume by

Waterline length x midship section area.



LCB: Longitudinal Center of Buoyancy, corresponding to the longitudinal

center of the immersed volume of the hull

LCF: Longitudinal Center of Flotation: weights added or removed at this

point will cause the vessel to rise or sink in the water without changing

trim.

TPC: Tonnes Per Centimetre immersion. The number of tonnes, added at the

LCF which will cause the vessel to sink by 1 centimeter.

MCT: Moment to Change Trim: The moment of weights added about the

LCF which will cause the trim to change by 1 cm.



5 KN Tables

These tables can be used to calculate the large angle stability of the vessel.

The stability of a vessel is determined by the tendency for the center of buoyancy (CB

in Figure 6) to move as the vessel heels. If this movement is such that the line of

action of the buoyancy force and the line of action of the weight of the vessel (acting

through the center of gravity (CG) form a couple that opposes the heel angle then the

vessel is said to be stable. The distance apart of the line of action of these two forces

is termed the righting lever or GZ. A graph of the righting lever (GZ) against heel

angle is called a GZ curve.

The distance KN can be calculated directly from the Maxsurf model (without

knowledge of the vertical center of gravity KG). The distance KN is the righting lever

assuming a KG of zero (i.e. CG on the keel)

Once the vertical center of gravity is known the GZ value can be calculated from the

KN value as follows:

GZ=KN-KGsinθ

Figure 6 Righting Lever GZ

As with initial stability, the key to determining the stability of the vessel is its vertical

center of gravity.



Once this is known and having found the displacement from the hydrostatic tables the

GZ curve can be derived from these tables (for displacements ranging from 706 to

1037 tonnes) as follows:

For each heel angle:

1. Interpolate KN for displacement from the two tables with trim below and

above the calculated trim.

2. Interpolate for the calculated trim to find the KN, at that heel angle for the

required displacement and trim.

3. Calculate the GZ value from the KG using the above formula.

Plot the calculated GZ values against heel angle to generate the GZ curve for that

loading condition.



6 Load Conditions

The load conditions considered are shown in Table 2.

The draughts for the first two load conditions are given on contemporary sailing trial

reports (Ref.1). These draughts were used to derive corresponding displacements and

longitudinal centers of gravity using the Maxsurf model.

The draughts for the design condition were scaled from the design draught and these

were used to derive the design displacement and LCG as above.

The vertical centers of gravity were calculated from the weight estimate as described

below.

The arrival condition displacement and vertical center of gravity were calculated from

the weight estimate assuming:

The quantities of stowage items given in Table 8.

Fully depleted shot and powder (as this gives a worst case for stability)

The same trim as the design condition (i.e. parallel rise)

Load Condition Draught

(AP)

Draught

(FP)

Displacement

(tonnes)

LCG VCG

Stored for 4 months

(Channel Service)

4.953 4.648 968 19.727 4.567

Stored for 6 months

(Foreign Service)

5.131 4.826 1029 19.694

4.411

Design Condition 4.851 4.496 925 19.708 4.681

Arrival Condition 4.504 4.148 809 19.777 5.085 Table 2 Load Conditions



7 Weight Estimate

As described above the displacement and LCG for a given set of draughts can be

derived from the geometry of the Maxsurf surface model. The purpose of creating a

weight breakdown is to estimate the vertical center of gravity and derive alternative

loading conditions.

The approach that was adopted for HMS Southampton was as follows:

A high level weight estimate for HMS Pearl (Ref. 1) provided a weight breakdown

for a similar sized frigate built soon after HMS Southampton. A comparison of the

principal particulars of the two vessels is given below:

HMS Pearl HMS Southampton

Gundeck Length (feet) 125.00 124.33

Length on keel (feet) 103.33 102.29

Breadth (feet) 35.17 34.67

Depth in hold (feet) 12.00 12.00

Tonnage 679 652

Table 3 Principal Particulars

It should be noted that the tonnage quoted in Table 3 is not the displacement of the

vessel but is a quantity calculated from the principal particulars and is related to the

total enclosed volume of the vessel.

The first level weight groups derived for HMS Southampton (as stored for 4 months

channel service) is shown in Table 4.

A detailed weight estimate is presented in Appendix 3.

Weight Group HMS Pearl

(tons)

HMS Pearl

(tonnes)

HMS Southampton

(tonnes)

HULL 516.400 524.662 479.229

ARMAMENT 73.450 74.625 74.625

TOP HAMPER 58.550 59.457 53.480

GROUND TACKLE 32.250 32.766 32.766

BOATS 2.290 2.997 2.997

STOWAGE 132.100 152.705 180.842

MEN AND EFFECTS 23.050 23.419 23.419

BALLAST 130.000 132.080 120.642

TOTAL 968.750 1002.741 968.000

Table 4 Weight Breakdown

For HMS Southampton a weight and center of gravity was calculated for each weight

group as follows:



7.1 Hull

Figure 7 CAD Surface Model used to estimate hull areas and vcg’s

The total weight of this group (together with the Top Hamper and ballast groups) was

determined by scaling the HMS Pearl weights with a common factor determined by

making the total displacement equal the 4 month stowed condition in Table 2, with

the stowage weights set to their 4 month values (See Section 7.6). This factor worked

out at approximately 0.91 (compared to the ratio of design displacements of 0.92).

The drawings were used to calculate the weights and center of gravity of the hull and

deck structure together with some of the fittings. A 3D CAD surface model was

created to help estimate the vertical centers and areas of the major planked areas

(outer and inner planking, decks and bulkheads see Figure 7). Other weights were

estimated by taking measurements from the drawings (e.g. calculating areas and

centroids using regions (AutoCad) and applying a thickness).

Appendix 3 contains comments on the method used to estimate the various

components in this group.

The balance between the calculated total and the scaled weight for the whole group

was added at a vertical center of gravity equal to the VCG of the combined total of the

calculated components. It should be noted that a number of approximations were

made in this weight estimate (e.g. inner planking thickness taken as 3” inside rather

than taking account of the varying thicknesses of the individual strakes). This could

be improved upon by building a mode detailed CAD model, or a detailed scale model

in wood.



7.2 Armament

The maximum amount of shot carried for channel and foreign service are given in

Ref. 1 as follows:

Ammunition Channel Service Foreign Service

Number Weight Number Weight

12 pounder round 1820 9.828 2600 14040

12 pounder grape 260 2.691 260 2.691

12 pounder dismantling 78 0.842 78 0.842

6 pounder round 420 1.134 600 1620

½ pounder round 600 0.135 720 162

TOTAL 14.630 TOTAL 19.355

Table 5 Ammunition - Shot

This shot was all located at the center of the shot locker in the weight estimate.

The HMS Pearl estimate divides this group into the groups shown in Table 6. As both

vessels are 32gun 12 pounder frigates the same weights were assumed for both

vessels.

Special 12 pounder guns were fitted to the 12 pounder 32 gun frigates weighing 28.5

cwt (1448 kg). These were shorter than the standard gun to allow room for the guns to

be worked on the relatively narrow upper decks of these ships. These were

individually positioned at VCG’s derived from the drawings. The six 6 pounder long

guns (16.5 cwt, 838kg) were centered 20” above the upper deck. The weight of the

swivel guns was scaled from a model of a swivel gun built for a model of the

schooner HMS Halifax (80 kg), and the VCG taken from the drawings. This only left

5kg to be added to align with the HMS Pearl data.

Powder and Gunners Stores assumed to be equal to the Pearl breakdown (and

constant for channel/foreign service) and were located in the magazine.

For the arrival condition it was assumed that all shot and powder had been consumed

(conservative).

The total weights of Armament for channel and foreign service departure load

conditions and the arrival conditions were, therefore, as set out in Table 6

HMS Pearl

(Tonnes)

HMS Southampton

Channel

Departure

Foreign

Departure

Arrival

Guns 43.637 43.637 43.637 43.637

Shot 14.630 14.630 19.355 0

Powder 6.909 6.909 6.909 0

Gunners

Stores

9.449 9.449 9.449 9.449

Table 6 Armament



7.3 Top Hamper

The data for HMS Pearl and as scaled for HMS Southampton is shown in Table 7.

A 3D model of the spars (excluding studding sail booms) was produced from the sail

plan, which was used to determine the vcg and weight (together with an assumed

density). Other weights (e.g. cross trees and caps) were calculated from the spar plan

(Ref.9). All yards were hoisted to the hounds. An additional 5.24 tonnes was added at

the same vcg to make up the required total.

Figure 8 3D Solid model used to calculate volume and vcg of Spars

Rigging was all assigned the same vcg.

The sail weight was divided between a vcg for the sail plan and the center of the sail

room. The weight of each sail was calculated from the sail area as measured from the

sail plan and the weight of cloth used (taken from Ref.2) with an additional 60%



(guess) to account for overlaps, bolt ropes, reef points etc. The vcg of each sail was

measured from the sail plan. This assumed all plain sails hoisted (Fore and Aft and

square but excluding studding sails) at a weight of 2.100 tonnes, with 3.679 tonnes in

the sail room (to reflect studding sails, spare sails, tarpaulins, spare cloth etc.)

HMS Pearl (tonnes) HMS Southampton

(tonnes)

Spars 30.074 26.939

Rigging 22.962 20.568

Sails 6.452 5.779 Table 7 Top Hamper

7.4 Ground Tackle

Ground Tackle was assumed as HMS Pearl:

Cables 25.298 tonnes vcg on cable tier (mid orlop platform).

Anchors 7.468 tonnes vcg from drawings

7.5 Boats

Weight assumed as HMS Pearl

7.6 Stowage

The HMS Pearl data breaks Stowage down into the 4 groups shown in Table 8. The

usage/month was calculated by assuming that Sea Stores are not consumed with time

and that the other groups are consumed at the same proportional rate. The difference

between the 6 month and 4 month stored conditions (Table 2) was used to define this

rate after correcting for the different ammunition carried for foreign and channel

service (hence ignoring any difference in stowage for channel and foreign service).

The arrival condition was calculated as 10% of the quantity calculated for foreign

service (stored for 6 months) departure.

HMS Pearl (3

months stores)

(tonnes)

1 months

usage

(tonnes)

HMS Southampton

6 months 4 months Arrival

Sea Stores 21.844 0.000 21.844 21.844 21.844

Water 43.434 9.339 71.451 52.773 7.145

Provisions 68.936 14.822 113.403 83.758 11.340

Fuel 18.491 3.976 30.419 22.467 3.042

Table 8 Stowage

All Stores were assumed to be located underneath the orlop deck.



These assumptions on stores were used to calculate the displacement and vertical

center of gravity at any stored condition.

7.7 Men and Effects

Men and effects were assumed the same weight as HMS Pearl shared equally between

the upper and lower decks.

7.8 Ballast

Ballast was scaled by the scaling factor. Iron Ballast was located in the hold (two pigs

deep) with shingle ballast at half depth of the hold.



8 Stability Criteria

Following a number of losses of sail training vessels due to capsize, work was carried

out by the Wolfson Unit at Southampton University to develop new stability criteria

for these vessels (Ref. 4). These were made part of the UK standards for Sailing

Vessels including a code of Large Yachts and Sail Training Vessels (Ref. 5)

The study found that:

Vessels with a range of stability of less than 90° degrees are vulnerable to

wind induced capsize, with the capsize arrested by the rig art 90° . They will

then remain at his angle until they sink through downflooding. This was the

means by which a number of sail training vessels have been lost (Ref. 6,7,8)

Wind tunnel tests on models found that wind heeling moments vary from a

maximum at 0° to approx zero at 90° with a good fit to a cos1.3

θ curve.

Gusts caused by turbulence in the atmospheric boundary layer commonly give

rise to short duration gusts which rarely exceed a velocity of 1.4 times the

hourly mean.

Squalls, caused by small scale weather systems can last for longer periods and

can give rise to wind speeds up to 10 times the mean for the previous hour.

The findings of the study were used to develop some very simple criteria. Firstly a

range of stability of 90° is required to reduce the risk of wind induced capsize.

Secondly, a maximum safe steady heel angle is calculated and recorded in the vessels

stability book. If the master of the vessel sets sail to ensure that the steady heel angle

does not exceed this value he can be confident that likelihood of encountering a gust

that will cause serious downflooding is very small. A further requirement of the

stability book is a graphical presentation of the maximum heel angle at which the

vessel may be sailed in a given wind speed in order to withstand a squall of a certain

strength. The intention being to provide the master with a tool to judge a safe heel

angle if conditions suggest that squalls are an imminent threat.

These criteria are defined in (Ref. 5) as follows:

1. GZ curves should be produced for Loaded Departure (100% consumables)

and Loaded Arrival (10% consumables) conditions. In the case of Military

Vessels the UK Navy’s approach is to consider the worst case distribution of

ammunition in the arrival condition

2. GZ curve should have a range of not less than 90°. A range of less than 90°

may be considered for vessels over 45m subject to agreed operational criteria.



3. The angle of steady heel should be greater than 15°. The angle of steady heel

is obtained from the intersection of a “derived heeling lever” curve with the

GZ curve

dwhl = derived wind heeling lever = 0.5 x WLO x cos1.3

θ

Where WLO = f

f

Cos

GZ3/1

Noting that

WLO Is the magnitude of the actual wind heeling lever at 0° which

would cause the vessel to heel to the down flooding angle θf or

60° whichever is least

GZf Is the lever of the vessel’s GZ at the down flooding angle θf or 60°

whichever is least

θd Is the angle at which the “derived wind heeling” curve intersects

the GZ curve (if θd is less than 15° the vessel is considered to have

insufficient stability).

θf The “down flooding angle is the angle of heel causing immersion

of the lower edge of openings having and aggregate area, in

square meters, greater than:

It might be noted that that if the vessel is sailed at an angle of heel no greater than

the “derived angle of heel”, it should be capable of withstanding a wind gust equal

to 1.4 times the steady wind speed (i.e. twice the steady wind pressure) without

immersing any downflooding openings or heeling beyond 60°.



Ref.5 also requires that sail training vessels should be subdivided into watertight

compartments such that they can survive flooding of any one compartment. HMS

Southampton was not fitted with any watertight bulkheads so would not be able to

comply. Survival following damage below the waterline would be down to the

rate at which the bilge pump could remove water and the speed at which holes

could be plugged.



9 Results

Results are presented for three of the loading conditions:

Loaded Departure (6 months foreign service)

Arrival Condition

Design Condition

It should be noted that none of these conditions have a range of stability of greater

than 90 degrees. This has the effect, in the latter two conditions, that it is not possible

to calcualate a WLO that would cause the vessel to heel to the downflood angle (or 60

degrees) . In these cases the WLO has been calculated as the minimum that would

cause the vessel to capsize (and the “effective downflood angle” becomes the angle at

which the gust heeling lever curve is tangential to the GZ curve).

Curves of maximum heel angle to prevent downflooding in gusts and squalls are

presented for the latter two conditions.



9.1 Departure Condition (Foreign Service 6 months)

Hydrostatics

Displacement Draft at FP

Draft at AP CP CB LCB LCF GMT TPC MCT

(tonnes) m m m m m tonne/cm tonne.m/cm

1029.44 4.826 5.131 0.640 0.460 0.746 0.174 1.430 3.475 8.303

GZ Curve

Heel angle 0 10 20 30 40 50 60 70 80 90 100

GZ m 0.000 0.247 0.471 0.599 0.628 0.580 0.469 0.315 0.137 -

0.048 -0.195

GZ Range 86.65 degrees

Gunport Imersion 26.03 degrees

Hatch Immersion 60.53 degrees

Max Steady Heel Angle 22.81 degrees



9.2 Arrival Condition

Hydrostatics




809.00 4.148 4.504 0.618 0.418 0.829 0.422 0.732 3.261 6.942

GZ Curve

Heel angle 0 10 20 30 40 50 60 70 80 90 100

GZ m 0.000 0.124 0.229 0.305 0.296 0.209 0.046 -0.168 -0.392 -0.582 -0.800




Effective Downflood angle 42.00 degrees




0

5

10

15

20

25

30

0 10 20 30 40 50 60

Ste

ad

y o

r M

ean

H

eel

An

gle

Mean Apparent Wind Speed

Curves of Maximum Steady Heel Angle to Prevent Downflooding in SquallsArrival Condition

30 knot squall

45 knot squall

60 knot squall

MSHA

Region B - Vulnerable to Gusts in this region

Region A – Vulnerable to Gusts

and Squalls in this region

Region C – Vulnerable

to Squalls in this region

Region D – Not Vulnerable to

Downflooding in this region



9.3 Design Condition

Hydrostatics




924.67 4.496 4.851 0.631 0.440 0.760 0.270 1.153 3.388 7.703

GZ Curve

Heel angle 0 10 20 30 40 50 60 70 80 90 100

GZ m 0.000 0.198 0.376 0.495 0.507 0.446 0.310 0.125 -0.080 -0.264 -0.428




Effective Downflood Angle 53.00 degrees




0

5

10

15

20

25

30

0 10 20 30 40 50 60

Ste

ad

y o

r M

ean

H

eel

An

gle

Mean Apparent Wind Speed

Curves of Maximum Steady Heel Angle to Prevent Downflooding in SquallsDesign Condition

30 knot squall

45 knot squall

60 knot squall

MSHA

Region B - Vulnerable to Gusts in this region

Region A – Vulnerable to Gusts

and Squalls in this region

Region C – Vulnerable

to Squalls in this region

Region D – Not Vulnerable to

Downflooding in this region



10 Discussion

Curves of stability were not calculated for ships in the 18th century. The importance of

large angle stability only becoming seriously recognised after the capsize of HMS

Captain in 1870. Figure 9 presents GZ curves for HMS Captain and HMS Monarch

(which was considered to have adequate stability)Ref.11. Whilst these ships were

substantially different from HMS Southampton, they were both military sailing ships

(albeit with steam auxiliary power) and so form some basis for comparison.

As can be seen from Figure 9 HMS Captain had a range of stability of 54.5 degrees.

However the GZ curve peaks at only 21 degrees meaning that if heeled beyond this

point the vessel would continue to heel over until its progress was stopped by the

rigging (at 90 degrees) at which point it would remain at 90 degrees until sinking by

downflooding. This was, in fact, what happened to HMS Captain.

Figure 9 GZ Curve for HMS Captain and HMS Monarch

This can be understood by looking at the GZ curve for HMS Southampton in the

arrival condition. It can be seen that a wind strength that can heel the vessel to more

than 40 degrees will continue to capsize the vessel, since at heel angles greater than

40 the wind heeling moment will be greater than the righting moment.

HMS Southampton, in the design condition, has a GZ curve similar to than of HMS

Monmouth (a similar angle of maximum GZ and a slightly greater range of stability).

A range of stability of 90 degrees is still not achieved, but the stability of the vessel

would have been considered adequate at the time (as it was with HMS Monarch). In

fact HMS Southampton was considered a stiff and seaworthy vessel in comparison

with similar vessels (Ref.1).



It is likely that the stability presented for the arrival condition would not have been

considered adequate in that the ability of the vessel to carry sail at moderate heel

angles would have been poor. It was common practice to fill empty casks with

seawater to maintain trim and stiffness as fresh water was consumed (Ref. 12). If this

was done such that the design draught and trim were maintained then the GZ curve

presented for the design condition would be the worst case in practice.

This gives a maximum steady heel angle to prevent capsize or downflooding in gusts

of 19.6 degrees. However gunport immersion occurs at around 30 degrees and so a

practical maximum heel angle of 15 degrees would have been sensible to minimise

risk of their immersion. Further work on a velocity prediction spreadsheet for HMS

Southampton (Ref. 13) suggests that this heel angle gives reasonable wind strengths

for reducing sail.



References

1. Gardiner, The first Frigates, Nine Pounder and Twelve Pounder Frigates,

1748-1815, Conway Maritime Press 1992.

2. David Steel, The Elements and Practice of Rigging and Seamanship, 1794

3. Stability of Surface Ships, Part 1 Conventional Ships, MAP 01-024, Sea

Systems Directorate, MoD Abbey Wood

4. B.Deakin, The Development of Stability Standards for UK Sailing Vessels,

Transactions of the Royal Institution of Naval Architects, 1991

5. Maritime and Coastguard Agency, LY2 The Large Commercial Yacht Code

6. Accident Report on the sinking of the Isaac H.Evans, U.S.Coastguard¸Jan

1985

7. Accident Report on the capsizing and sinking of the US Sailing Vessel Pride

of Baltimore, U.S.National Transportation Safety Board, March 1987

8. Grieg. C and Sutton F, The last voyage of the Albatross, Ducell, Sloan and

Pearce

9. R.Braithwaite, Notes to accompany the reconstructed drawings of HMS

Southampton. http://richardsmodelboats.webs.com

10. R.Braithwaite, Velocity Prediction of the 32 Gun Frigate HMS Southampton.

http://richardsmodelboats.webs.com

11. L Attwood, Theoretical Naval Architecture, Edward 1922

12. B Lavery, The Arming and Fitting of English Ships of War 1600-

1815,Conway 1987.

13. R.Braithwaite, HMS Southampton, Velocity Prediction

http://richardsmodelboats.webs.com/

http://richardsmodelboats.webs.com/



Appendix 1 Hydrostatic Tables



Hydrostatics for Trim =0

Midship Draught 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5

Displacement tonne 706.8 738.1 769.9 802.1 834.5 867.5 900.9 934.6 968.6 1003 1037

Heel to Starboard degrees 0 0 0 0 0 0 0 0 0 0 0

Draft at FP m 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5

Draft at AP m 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5

Draft at LCF m 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5

Trim (+ve by stern) m 0 0 0 0 0 0 0 0 0 0 0

WL Length m 39.807 39.86 39.91 39.968 39.949 39.901 39.949 40.013 40.088 40.166 40.243

WL Beam m 10.43 10.483 10.513 10.539 10.564 10.576 10.588 10.598 10.601 10.604 10.602

Wetted Area m^2 469.912 479.467 488.993 498.442 507.254 513.552 522.777 531.996 541.168 550.279 559.536

Waterpl. Area m^2 303.005 307.516 311.783 315.828 319.713 323.318 326.75 330.015 333.056 335.872 338.474

Prismatic Coeff. 0.601 0.605 0.608 0.612 0.617 0.622 0.626 0.629 0.633 0.636 0.639

Block Coeff. 0.415 0.42 0.426 0.432 0.438 0.446 0.452 0.457 0.463 0.469 0.474

Midship Area Coeff. 0.692 0.696 0.702 0.707 0.712 0.717 0.723 0.728 0.733 0.738 0.743

Waterpl. Area Coeff. 0.73 0.736 0.743 0.75 0.758 0.766 0.772 0.778 0.784 0.789 0.793

LCB from Amidsh. (+ve fwd) m 1.223 1.202 1.181 1.16 1.134 1.111 1.087 1.063 1.039 1.015 0.991

LCF from Amidsh. (+ve fwd) m 0.768 0.717 0.663 0.609 0.556 0.508 0.459 0.408 0.359 0.313 0.266

KB m 2.602 2.663 2.725 2.786 2.847 2.908 2.968 3.029 3.089 3.15 3.21

BMt m 3.161 3.118 3.068 3.016 2.964 2.909 2.853 2.797 2.739 2.681 2.622

BML m 35.864 35.366 34.899 34.444 34.004 33.537 33.095 32.666 32.237 31.8 31.364

KMt m 5.763 5.781 5.793 5.802 5.811 5.817 5.822 5.826 5.829 5.831 5.832

KML m 38.466 38.029 37.624 37.23 36.851 36.445 36.063 35.695 35.326 34.949 34.573

Immersion (TPc) tonne/cm 3.106 3.153 3.196 3.238 3.278 3.315 3.35 3.383 3.414 3.443 3.47

MTc tonne.m 6.363 6.559 6.76 6.959 7.157 7.347 7.539 7.73 7.917 8.098 8.274

RM at 1deg = GMt.Disp.sin(1) tonne.m 17.434 18.434 19.387 20.322 21.273 22.207 23.139 24.07 24.994 25.917 26.83

Max deck inclination deg 0 0 0 0 0 0 0 0 0 0 0

Trim angle (+ve by stern) deg 0 0 0 0 0 0 0 0 0 0 0



Hydrostatics for Trim =0.1m

Midship Draught 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5



Draft at FP m 3.95 4.05 4.15 4.25 4.35 4.45 4.55 4.65 4.75 4.85 4.95

Draft at AP m 4.05 4.15 4.25 4.35 4.45 4.55 4.65 4.75 4.85 4.95 5.05

Draft at LCF m 3.998 4.098 4.198 4.299 4.399 4.499 4.599 4.699 4.799 4.899 4.999

Trim (+ve by stern) m 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1

WL Length m 39.779 39.827 39.876 39.911 39.847 39.85 39.914 39.978 40.046 40.124 40.201

WL Beam m 10.429 10.482 10.513 10.538 10.564 10.576 10.588 10.598 10.601 10.604 10.602

Wetted Area m^2 470.141 479.712 489.228 498.682 508.107 513.814 523.053 532.26 541.419 550.525 559.69

Waterpl. Area m^2 303.326 307.865 312.159 316.202 320.101 323.697 327.151 330.412 333.432 336.246 338.814

Prismatic Coeff. 0.601 0.605 0.609 0.613 0.619 0.623 0.627 0.63 0.633 0.636 0.639

Block Coeff. 0.41 0.415 0.421 0.427 0.434 0.441 0.447 0.453 0.459 0.464 0.47



LCB from Amidsh. (+ve fwd) m 1.128 1.109 1.089 1.069 1.047 1.022 1 0.977 0.954 0.931 0.908


KB m 2.601 2.662 2.724 2.785 2.846 2.907 2.968 3.028 3.089 3.149 3.209

BMt m 3.166 3.123 3.073 3.02 2.967 2.913 2.857 2.8 2.742 2.684 2.625

BML m 36.009 35.514 35.047 34.589 34.144 33.675 33.238 32.802 32.363 31.922 31.467

KMt m 5.767 5.785 5.797 5.805 5.814 5.82 5.825 5.829 5.831 5.833 5.835

KML m 38.61 38.177 37.771 37.374 36.991 36.582 36.206 35.831 35.452 35.071 34.677


MTc tonne.m 6.385 6.584 6.785 6.986 7.186 7.376 7.57 7.761 7.947 8.128 8.301


Max deck inclination deg 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2

Trim angle (+ve by stern) deg 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2




Midship Draught 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5

Displacement tonne 705.6 737 768.9 801.1 833.8 866.8 900.2 933.9 968 1002 1037


Draft at FP m 3.9 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9

Draft at AP m 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5 5.1

Draft at LCF m 3.997 4.097 4.197 4.297 4.398 4.498 4.598 4.698 4.799 4.899 4.999

Trim (+ve by stern) m 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2

WL Length m 39.746 39.795 39.844 39.81 39.766 39.816 39.88 39.944 40.008 40.083 40.16

WL Beam m 10.429 10.482 10.513 10.538 10.563 10.576 10.588 10.598 10.601 10.604 10.602

Wetted Area m^2 470.373 479.96 489.471 498.933 505.331 514.06 523.325 532.528 541.663 550.789 559.828

Waterpl. Area m^2 303.642 308.206 312.519 316.58 320.407 324.041 327.526 330.801 333.783 336.621 339.185

Prismatic Coeff. 0.602 0.606 0.609 0.615 0.62 0.624 0.627 0.631 0.634 0.637 0.64

Block Coeff. 0.404 0.41 0.416 0.423 0.43 0.436 0.442 0.448 0.454 0.46 0.466





KB m 2.6 2.662 2.723 2.785 2.846 2.907 2.968 3.028 3.089 3.149 3.209

BMt m 3.171 3.127 3.078 3.025 2.971 2.916 2.86 2.803 2.745 2.687 2.628

BML m 36.148 35.661 35.191 34.732 34.249 33.801 33.372 32.934 32.482 32.044 31.583

KMt m 5.771 5.789 5.801 5.81 5.817 5.823 5.827 5.832 5.834 5.836 5.837

KML m 38.748 38.323 37.914 37.516 37.094 36.707 36.34 35.963 35.571 35.193 34.792


MTc tonne.m 6.406 6.608 6.811 7.012 7.206 7.402 7.6 7.792 7.976 8.16 8.332







Midship Draught 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5



Draft at FP m 3.85 3.95 4.05 4.15 4.25 4.35 4.45 4.55 4.65 4.75 4.85

Draft at AP m 4.15 4.25 4.35 4.45 4.55 4.65 4.75 4.85 4.95 5.05 5.15

Draft at LCF m 3.995 4.096 4.196 4.296 4.397 4.497 4.597 4.698 4.798 4.898 4.999

Trim (+ve by stern) m 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3

WL Length m 39.714 39.763 39.785 39.713 39.719 39.783 39.847 39.911 39.975 40.042 40.119

WL Beam m 10.428 10.481 10.512 10.538 10.563 10.576 10.588 10.598 10.601 10.604 10.602

Wetted Area m^2 470.622 480.195 489.72 499.191 505.574 514.913 523.591 532.793 541.914 551.027 557.643

Waterpl. Area m^2 303.968 308.541 312.872 316.95 320.777 324.42 327.879 331.158 334.137 336.949 339.439

Prismatic Coeff. 0.602 0.606 0.61 0.616 0.621 0.624 0.628 0.631 0.635 0.638 0.641

Block Coeff. 0.399 0.405 0.411 0.419 0.426 0.432 0.438 0.444 0.45 0.456 0.461





KB m 2.6 2.661 2.723 2.784 2.846 2.907 2.968 3.028 3.089 3.149 3.21

BMt m 3.176 3.131 3.082 3.029 2.975 2.919 2.863 2.806 2.747 2.689 2.631

BML m 36.288 35.801 35.33 34.873 34.384 33.932 33.498 33.057 32.6 32.151 31.67

KMt m 5.776 5.793 5.805 5.813 5.821 5.826 5.83 5.835 5.836 5.838 5.841

KML m 38.888 38.462 38.053 37.658 37.23 36.839 36.466 36.086 35.689 35.301 34.88


MTc tonne.m 6.427 6.631 6.835 7.039 7.233 7.431 7.628 7.821 8.005 8.187 8.353







Midship Draught 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5

Displacement tonne 704.7 736.1 768 800.4 833.2 866.3 899.7 933.5 967.7 1002 1037


Draft at FP m 3.8 3.9 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8

Draft at AP m 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5 5.1 5.2

Draft at LCF m 3.994 4.095 4.195 4.296 4.396 4.497 4.597 4.697 4.798 4.898 4.999

Trim (+ve by stern) m 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4

WL Length m 39.683 39.731 39.689 39.642 39.686 39.75 39.814 39.877 39.941 40.005 40.078

WL Beam m 10.427 10.48 10.512 10.537 10.563 10.576 10.588 10.598 10.601 10.604 10.602

Wetted Area m^2 470.854 480.428 489.952 496.389 505.774 515.137 523.837 533.022 542.168 551.231 557.845

Waterpl. Area m^2 304.293 308.888 313.225 317.23 321.11 324.786 328.227 331.486 334.502 337.241 339.783

Prismatic Coeff. 0.602 0.606 0.612 0.617 0.621 0.625 0.628 0.632 0.635 0.639 0.642

Block Coeff. 0.394 0.4 0.407 0.415 0.421 0.427 0.433 0.439 0.445 0.451 0.457





KB m 2.6 2.661 2.723 2.785 2.846 2.907 2.968 3.029 3.09 3.15 3.21

BMt m 3.18 3.136 3.086 3.033 2.979 2.922 2.865 2.808 2.75 2.691 2.633

BML m 36.428 35.942 35.467 34.969 34.505 34.063 33.62 33.17 32.722 32.247 31.781

KMt m 5.78 5.797 5.81 5.817 5.825 5.83 5.834 5.837 5.839 5.841 5.843

KML m 39.028 38.603 38.19 37.753 37.351 36.97 36.588 36.199 35.811 35.397 34.991


MTc tonne.m 6.45 6.655 6.86 7.057 7.257 7.459 7.655 7.847 8.035 8.212 8.383







Midship Draught 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5



Draft at FP m 3.75 3.85 3.95 4.05 4.15 4.25 4.35 4.45 4.55 4.65 4.75

Draft at AP m 4.25 4.35 4.45 4.55 4.65 4.75 4.85 4.95 5.05 5.15 5.25

Draft at LCF m 3.993 4.094 4.195 4.295 4.396 4.496 4.597 4.697 4.798 4.898 4.999

Trim (+ve by stern) m 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5

WL Length m 39.651 39.666 39.594 39.603 39.658 39.717 39.781 39.845 39.908 39.972 40.038

WL Beam m 10.427 10.48 10.512 10.537 10.562 10.576 10.588 10.598 10.601 10.604 10.602

Wetted Area m^2 471.122 480.714 490.242 496.663 506.054 515.408 524.703 533.293 542.446 549.075 558.02

Waterpl. Area m^2 304.614 309.224 313.579 317.579 321.468 325.133 328.561 331.786 334.808 337.472 340.03

Prismatic Coeff. 0.603 0.607 0.613 0.618 0.622 0.625 0.629 0.633 0.636 0.639 0.642

Block Coeff. 0.39 0.396 0.403 0.41 0.417 0.423 0.429 0.435 0.441 0.447 0.453





KB m 2.6 2.662 2.724 2.785 2.847 2.908 2.969 3.03 3.09 3.151 3.211

BMt m 3.185 3.14 3.091 3.036 2.982 2.925 2.868 2.81 2.752 2.693 2.634

BML m 36.562 36.076 35.601 35.098 34.636 34.186 33.732 33.274 32.825 32.33 31.859

KMt m 5.785 5.802 5.814 5.822 5.829 5.833 5.837 5.84 5.842 5.844 5.846

KML m 39.162 38.738 38.324 37.883 37.483 37.093 36.701 36.304 35.915 35.481 35.07


MTc tonne.m 6.471 6.678 6.884 7.082 7.284 7.485 7.682 7.872 8.061 8.231 8.404






Appendix 2 – KN Tables



KN Values

Initial Trim 0.0 m

Displacement 0 10 20 30 40 50 60 70 80 90 100

706.8 0 0.998 1.952 2.836 3.589 4.153 4.524 4.702 4.728 4.555 4.223

739.8 0 1 1.956 2.84 3.58 4.135 4.497 4.668 4.691 4.537 4.215

772.8 0 1.002 1.96 2.842 3.569 4.117 4.47 4.637 4.655 4.52 4.208

805.9 0 1.004 1.963 2.842 3.558 4.099 4.444 4.608 4.621 4.499 4.201

838.9 0 1.006 1.967 2.841 3.546 4.079 4.419 4.581 4.591 4.477 4.194

871.9 0 1.007 1.969 2.838 3.532 4.058 4.394 4.556 4.566 4.455 4.187

904.9 0 1.008 1.972 2.833 3.518 4.036 4.369 4.532 4.543 4.433 4.179

937.9 0 1.009 1.974 2.827 3.502 4.014 4.344 4.51 4.523 4.412 4.171

971 0 1.01 1.976 2.819 3.486 3.992 4.322 4.489 4.504 4.393 4.163

1004 0 1.01 1.977 2.809 3.47 3.968 4.299 4.469 4.488 4.376 4.154

1037 0 1.011 1.976 2.797 3.453 3.945 4.276 4.45 4.472 4.361 4.146

Initial Trim 0.1 m Displacement 0 10 20 30 40 50 60 70 80 90 100

706.2 0 0.998 1.953 2.837 3.591 4.155 4.527 4.703 4.732 4.559 4.224

739.3 0 1.001 1.957 2.841 3.582 4.137 4.499 4.67 4.693 4.539 4.217

772.4 0 1.003 1.961 2.843 3.572 4.12 4.472 4.639 4.656 4.522 4.21

805.4 0 1.005 1.964 2.844 3.561 4.101 4.447 4.61 4.621 4.502 4.203

838.5 0 1.006 1.968 2.843 3.548 4.082 4.421 4.583 4.591 4.48 4.196

871.6 0 1.008 1.971 2.84 3.534 4.061 4.396 4.558 4.565 4.456 4.189

904.7 0 1.009 1.973 2.835 3.52 4.039 4.371 4.534 4.543 4.433 4.182

937.8 0 1.01 1.975 2.829 3.505 4.017 4.348 4.512 4.523 4.411 4.173

970.8 0 1.01 1.977 2.82 3.489 3.995 4.325 4.491 4.505 4.391 4.164

1004 0 1.011 1.978 2.81 3.472 3.971 4.301 4.471 4.489 4.374 4.155

1037 0 1.011 1.977 2.799 3.455 3.948 4.278 4.451 4.474 4.36 4.146



KN Values


705.6 0 0.999 1.954 2.838 3.593 4.157 4.529 4.706 4.736 4.562 4.226

738.7 0 1.001 1.958 2.842 3.584 4.139 4.502 4.672 4.695 4.542 4.219

771.9 0 1.003 1.962 2.844 3.574 4.122 4.475 4.641 4.656 4.523 4.212

805 0 1.005 1.965 2.845 3.563 4.104 4.449 4.612 4.621 4.504 4.205

838.2 0 1.007 1.969 2.844 3.55 4.084 4.424 4.585 4.59 4.482 4.198

871.3 0 1.008 1.972 2.841 3.536 4.063 4.399 4.559 4.564 4.458 4.191

904.4 0 1.009 1.974 2.837 3.522 4.042 4.374 4.536 4.542 4.433 4.184

937.6 0 1.01 1.977 2.83 3.507 4.02 4.351 4.513 4.523 4.41 4.176

970.7 0 1.011 1.978 2.822 3.491 3.997 4.327 4.492 4.506 4.39 4.166

1004 0 1.012 1.979 2.812 3.474 3.974 4.304 4.472 4.49 4.373 4.156

1037 0 1.012 1.979 2.801 3.457 3.951 4.281 4.453 4.475 4.36 4.146


705.1 0 0.999 1.955 2.84 3.594 4.159 4.532 4.707 4.74 4.564 4.227

738.3 0 1.002 1.959 2.843 3.586 4.141 4.505 4.674 4.697 4.544 4.221

771.5 0 1.004 1.963 2.846 3.576 4.124 4.478 4.642 4.656 4.524 4.214

804.7 0 1.006 1.967 2.847 3.565 4.106 4.452 4.613 4.621 4.506 4.208

837.9 0 1.007 1.97 2.846 3.552 4.087 4.427 4.586 4.59 4.484 4.2

871.1 0 1.009 1.973 2.843 3.539 4.066 4.401 4.561 4.564 4.459 4.193

904.2 0 1.01 1.975 2.839 3.524 4.045 4.378 4.537 4.542 4.433 4.186

937.4 0 1.011 1.978 2.832 3.509 4.023 4.354 4.515 4.523 4.409 4.178

970.6 0 1.012 1.98 2.824 3.493 4 4.33 4.494 4.507 4.389 4.168

1004 0 1.012 1.98 2.814 3.476 3.977 4.306 4.474 4.491 4.372 4.157

1037 0 1.013 1.98 2.802 3.459 3.953 4.283 4.455 4.477 4.36 4.146



KN Values


704.7 0 1 1.956 2.841 3.596 4.161 4.534 4.709 4.743 4.567 4.229

737.9 0 1.002 1.96 2.845 3.588 4.144 4.507 4.675 4.698 4.547 4.223

771.2 0 1.005 1.964 2.847 3.578 4.127 4.481 4.644 4.656 4.527 4.216

804.4 0 1.007 1.968 2.848 3.567 4.109 4.455 4.615 4.62 4.507 4.21

837.6 0 1.008 1.971 2.847 3.554 4.089 4.429 4.588 4.59 4.486 4.203

870.9 0 1.009 1.974 2.845 3.541 4.068 4.404 4.563 4.564 4.461 4.195

904.1 0 1.011 1.977 2.84 3.526 4.047 4.38 4.539 4.542 4.433 4.188

937.3 0 1.012 1.979 2.834 3.511 4.025 4.356 4.516 4.524 4.408 4.18

970.5 0 1.012 1.981 2.825 3.495 4.002 4.333 4.495 4.507 4.388 4.17

1004 0 1.013 1.981 2.815 3.478 3.979 4.309 4.475 4.492 4.372 4.159

1037 0 1.013 1.981 2.804 3.461 3.955 4.285 4.456 4.479 4.361 4.146


704.3 0 1.001 1.957 2.842 3.599 4.163 4.537 4.711 4.746 4.57 4.23

737.5 0 1.003 1.961 2.846 3.59 4.146 4.51 4.677 4.699 4.549 4.224

770.6 0 1.005 1.965 2.849 3.58 4.129 4.484 4.646 4.656 4.529 4.218

803.8 0 1.007 1.969 2.85 3.569 4.111 4.458 4.617 4.621 4.509 4.212

837 0 1.009 1.972 2.849 3.556 4.092 4.432 4.59 4.59 4.487 4.205

870.1 0 1.01 1.975 2.846 3.543 4.071 4.408 4.565 4.565 4.462 4.197

903.3 0 1.011 1.978 2.842 3.528 4.05 4.384 4.541 4.543 4.432 4.19

936.5 0 1.012 1.98 2.835 3.513 4.028 4.36 4.518 4.525 4.407 4.181

969.7 0 1.013 1.982 2.827 3.497 4.005 4.336 4.497 4.509 4.387 4.172

1003 0 1.013 1.983 2.817 3.48 3.982 4.312 4.477 4.494 4.373 4.16

1036 0 1.014 1.982 2.805 3.463 3.958 4.288 4.458 4.48 4.362 4.147



Appendix 3 Weight Estimate

Load Condition:

Foreign Service

Stored for 6 months



HULL 479229 4.399 scaled

weight VCG COMMENTS

Item (kg) (m)

Hull

Outer hull planking bottom 33387 2.499

Area and vcg from Surface model trimmed under wale

Outer hull planking wale 7960 5.351 Area and vcg from Surface model trimmed to wale

Outer hull planking topsides 13588 7.243

Area and vcg from Surface model trimmed above wale

Inner Hull Planking 48779 4.449

Area and vcg from Surface model assumed 3" overall

Stern planking (external) 1101 7.637 Area and vcg from Surface model (2")

Stern planking (internal) 1101 7.637 "

Crutch 157 2.896

Hull Frames 121000 3.284 weight & cg calculated from drg

Stern Timbers 911 7.795

area and vcg calculated from drawing (region) thickness from contract

Transoms 1188 5.551 "

Hawse Timbers 4169 5.553 "

Keel 4788 0.227 "

stem 458 3.011 "

knee of stem etc 2029 5.125 "

stemson etc 711 3.995 "

sternpost 1029 3.176 "

deadwood 5848 1.320 "

keelson 3567 1.422 "

breasthooks below lower deck 684 3.861 weight & cg calc form drg/Eolus Contract

Head rails 482 7.290 weight & cg calc form drg

Main Channels 412 8.115 weight & cg calc form drg/Eolus Contract

Fore Channels 328 8.204 "

Mizzen Channels 226 8.585 "

0 0.000

Bulkheads 0 0.000

Beakhead Bulkhead planking 468 8.128 weight & cg calc form drg

Beakhead bulkhead stiffeners 301 8.128 "

Upper deck divisions -panels 956 7.777 Area and vcg from surface model

-stanchions 199 7.777 Assumed 3'spacing

Lower deck divisions -panels 2732 5.703 Area and vcg from surface model


below lower deck divisions -panels 3276 3.985

Area and vcg from surface model


Wells 1030 1.895 weight & cg calc form drg

Shot Locker 315 1.895 "

Magazine bulkheads 3016 2.828 Area and vcg from surface model

Magazine stiffeners 126 2.828

0 0.000



weight VCG COMMENTS

Item (kg) (m)

Decks 0 0.000

Quarter Deck 0 0.000

Quarter Deck Planking 5236 8.789 Area and vcg from surface model

quarterdeck lodging knees 534 8.732 weight & cg calc from drg

quarterdeck hanging knees 749 7.950 "

Quarterdeck beams 3365 8.707 "

stern beam? 264 8.697 "

carlings 326 8.707 "

0 0.000

Foredeck 0 0.000

Foredeck planks 2506 8.522 Area and vcg from surface model

foredeck lodging knees 437 8.465 weight & cg calc from drg

foredeck hanging knees 613 8.459 "

Foredeck beams 1529 8.440 "

Forward Beam 463 8.440 "

carlings 55 8.440 "

cathead Beam 657 8.376 "

0 0.000

0 0.000

Upper Deck 0 0.000

Upper Deck Planking 21377 6.669 Area and vcg from Surface model

breasthook 474 6.862 wt from drg cg from surface

transom 626 6.869 "

Curvrd beams 1206 6.555 "

lodging knees 3514 6.580 "

hanging knees 3096 6.580 "

Mast Partners 1369 6.555 "

Upper Deck Beams (main) 11614 6.555 "

Upper Deck Beams (minor aft) 440 6.599 "

carlings (longitudinal) 2218 6.599 "

Ledges 2523 6.628 "

0 0.000

Lower Deck 0 0.000

Lower Deck Planking 16722 4.779 Area and vcg from surface model

breasthook 322 5.004 weight & cg calc from drg

transom 0 0.000 "

Curvrd beams 652 4.677 "

lodging knees 3275 4.690 "

hanging knees 3301 4.690 "

Mast Partners 1100 4.677 "

Lower Deck Beams 8601 4.677 "

carlings (longitudinal) 2755 4.710 "

Ledges 2624 4.738 "

Standards 747 5.328



weight VCG COMMENTS

Item (kg) (m)

Orlop Platforms 0 0.000

0 0.000

Fwd Platform planks 1905 3.180 Area and vcg from surface model

lodging knees 1176 3.091 area from drawing, vcg 1/2 thickness fro deck

Fwd Platform beams 2555 3.066 total length measured from drawing

0 0.000

Mid Platform planks 2983 3.128 Area and vcg from surface model


Mid Platform beams 1988 3.014 total length measured from drawing

0 0.000 "

Aft Platform planks 1149 2.946 Area and vcg from surface model


Aft Platform beams 1103 2.832 total length measured from drawing

0 0.000

Fittings 0 0.000

Foremast step 838 2.087 weight & cg calc from drg/Eolus Contract

Mainmast step 915 1.380 "

Mizzen mast step 214 2.058 "

Bowsprit step 162 5.867 "

0 0.000

0 0.000

Bits 0 0.000

Lower ~Deck aft 0 0.000

Stanchions 670 3.943 weight & cg calc from drg/Eolus Contract

Standard 181 5.146


Cross piece 28 5.480 weight & cg calc from drg/Eolus Contract

Lower Deck fwd 0 0.000

Standard 306 5.424


Cross Piece 28 5.555 weight & cg calc from drg/Eolus Contract

Upper Deck aft 0 0.000

0 0.000

0 0.000

Upper Deck Fwd 0 0.000

0 0.000

Stove 1000 7.169 Guess

Chain Pumps 1000 2.946 Guess

Capstans 1725 6.525 weight and cg from 3d model

0 0.000

Pillars 0 0.000

Lower Deck 792 2.921 weight & cg calc from drg/Eolus Contract

Upper Deck 216 5.639 "



weight VCG COMMENTS

Item (kg) (m)

Ladders 0 0.000

lower-upper- 1 Sides 29 5.592 weight & cg calc from drg

- rungs 35 5.592 weight & cg calc from drg

lower-upper- 2 Sides 29 5.592 weight & cg calc from drg


orlop-lower- 1 Sides 29 3.763 weight & cg calc from drg


orlop-lower- 2 Sides 29 3.763 weight & cg calc from drg


0 0.000

0 0.000

Rails 497 8.433 weight & cg calc from drg

0 0.000

Rudder 1326 3.062


Tiller 378 6.375 weight and cg from drawing

Wheel 110 9.728 weight and cg from 3d model

0 0.000

0 0.000

0 0.000

Fastenings 20000 4.400 Guess

Misc 62508 4.450

to make total up to scaled value, c.g as calculated items above



ARMAMENT 79350 6.243

Guns 43637 7.796 as Pearl cg calculatd

weight VCG COMMENTS

Item (kg) (m)

12 pdr bow port 2896 7.821 28.5cwt gun centered in port

12 pdr port 2 2896 7.664 "

12 pdr port 3 2896 7.566 "

12 pdr port 4 2896 7.498 "

12 pdr port 5 2896 7.439 "

12 pdr port 6 2896 7.395 "

12 pdr port 7 2896 7.381 "

12 pdr port 8 2896 7.394 "

12 pdr port 9 2896 7.440 "

12 pdr port 10 2896 7.504 "

12 pdr port 11 2896 7.576 "

12 pdr port 12 2896 7.663 "

12 pdr port 13 2896 7.787 "

6pdr (foredeck) 1676 9.017 16.5cwt gun 20" above deck

6 pdr (quarterdeck) 3353 9.322 "

swivel guns 960 10.033 scaled from a 1/16 model

Misc 5 7.796 to make up total

0 0.000

Shot 19355 5.850 as Pearl

weight VCG COMMENTS

Item (kg) (m)

12 pounder shot 14040 1.895 Calculated positioned in shot locker

12 pounder grape 2691 1.895 "

12 pounder double 842 1.895 "

6 pounder shot 1620 1.895 "

1/2 pounder shot 162 1.895 "

Powder 6909 2.565 as Pearl

Gunners Stores 9449 2.565 as Pearl



TOP HAMPER 53480 17.149 scaled

Spars 27037 17.977 scaled

weight VCG COMMENTS

Item (kg) (m)

Main mast 4090 12.649 3d solid CAD Model

Main topmast 961 29.362 "

Main topgallant 197 41.072 "

Fore mast 2875 12.243 "

Fore topmast 842 26.949 "

Fore topgallant 135 37.323 "

Mizzen mast 1514 12.044 "

Mizzen topmast 412 27.924 "

Bowsprit 2674 9.578 "

Jibboom 441 14.517 "

Main yard 1577 21.370 "

Main topsail yard 541 35.200 "

Main topgallant yard 109 42.955 "

Fore yard 1093 19.788 "

Fore topsail yard 372 32.171 "

Fore topgallant yard 79 39.141 "

Mizzen Yard 738 19.042 "

Mizzen topsail yard 101 31.007 "

Mizzen crossjack 364 20.161 "

Spritsail yard 369 11.066 "

Sprit topsail yard 0 0.000 "

Fittings 0 0.000

Mainmast Trestle trees 333 23.231 calculated weight and cg from dwg

Mainmast Cross Trees 287 23.231 "

Mainmast cap 314 26.756 "

Maintopmast Trestle trees 26 36.590 "

Maintopmast Cross Trees 56 36.590 "

Maintopmast cap 54 38.080 "

Foremast Trestle trees 235 21.708 "

Foremast Cross Trees 202 21.708 "

Foremast cap 292 24.548 "

Foretopmast Trestle trees 19 33.542 "

Foretopmast Cross Trees 40 33.542 "

Foretopmast cap 37 34.920 "

Mizzenmast Trestle trees 107 21.619 "

Mizzenmast Cross Trees 91 21.619 "

Mizzenmast cap 87 23.860 "

Bowsprit Cap 37 13.989 "

0 0.000

Misc 5338 17.977 to make up total

0 0.000

Rigging 20643 17.977 scaled weight vcg as spars

Sails 5800 10.345 scaled



weight VCG COMMENTS

Item (kg) (m)

Square

Main Course 317 15.792

Area and vcg from drg. Weight taken as area x cloth weight x 1.6

Main topsail 304 28.053 "

Main Topgallant 74 38.923 "

Fore course 225 15.185 "

Fore topsail 238 25.824 "

Fore topgallant 58 35.536 "

Mizzen Topsail 126 25.708 "

Spritsail 94 8.315 "

Fore and Aft 0 0.000 "

Mizzen Course 105 16.743 "

Main Staysail 91 14.850 "

Main topmast Staysail 127 20.961 "

Main topgallant Staysail 63 32.598 "

Fore Staysail 51 14.945 "

Fore Topmast Staysail 43 17.724 "

Jib 68 21.229 "

Mizzen Staysail 76 14.395 "

Mizzen topmast staysail 42 22.407 "

0 0.000

Sails, tarpaulins etc. in Sail room 3700 4.094

to make up total placed in sail room 36" above orlop

0 0.000



GROUND TACKLE 32766 4.416 as Pearl

Cables 25298 3.328 as Pearl vcg 200mm above orlop

Anchors 7468 8.103 as Pearl

BOATS 2997 8.128 as Pearl

STOWAGE 237117 2.100

Sea Stores 21844 2.100

Calculated based on stored condition. Located In hold

Water 71451 2.100 "

Provisions 113403 2.100 "

Fuel 30419 2.100 "

0 0.000

0 0.000

0 0.000

0 0.000

MEN AND EFFECTS 23419 6.024 as Pearl vcg 300mm above upper and lower deck

BALLAST 120642 1.740 Scaled

Iron 46401 1.130 Scaled vcg 6" above inner planks at midships

Shingle 74241 2.121

Scaled vcg 1/2 depth from top of iron ballast to underside of orlop beams

TOTAL 1029000 4.411

32 gun frigate - richards model boats - home stability report... · this report relates to a...

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