Variables used in calculations
www.kp44.org — The official website of the Peterson Cutter Owner's Group

NOTE: The variables applicable to ground tackle loading are shown in green

   

Data for KP44

   

length overall (LOA)

44

feet

length of waterline (LWL)

38

feet

beam @ maximum

12.5

feet

beam @ water line

12

feet

draft

6.5

feet

displacement in pounds (D)

30,000

pounds

center of buoyancy

53.5%

aft

waterline area

576

square feet

center of floatation

55.3%

aft

sail area

1,869

square feet

moment to trim 1"

9,500

 

moment to heel 10

6,100

 

prismatic coefficient

0.559

 

waterplane coefficient

0.717

 

displacement to length ratio

244

 

cross-sectional area presented to wind (A)

140

square feet

cross-sectional area @ 300 yaw (A300)

310

square feet

Drag Coefficient (Cd)@ 00 Attack Angle

0.77

Surge Factor (sf)

2.4

 

Dynamic Wind Pressure

Wind Speed in Knots

Beaufort

Wind Pressure (lbs/ft2)

10

3

0.33

20

5

1.3

30

7

3

40

8

5

50

10

8

60

11

12

70

12

17

80

13

22

90

15

28

100

16

34

 

Ground Tackle Loads

Wind Speed in Knots

Drag Force with No Surge

Drag Force with Surge

10

79

192

20

309

755

30

714

1,742

40

1,190

2,904

50

1,903

4,646

60

2,855

6,969

70

4,045

9,873

80

5,235

12,776

90

6,662

16,261

100

8,090

19,745

 

Scope vs Depth

5/16 HT chain 3/8 Proof Coil chain
Lb/ft = 1.20   Lb/ft = 1.66  
Water Depth Length Scope Weight Length Scope Weight
10 230 23:1 276 130 13:1 216
15 245 16:1 294 145 10:1 241
20 260 13:1 312 160 8:1 266
25 275 11:1 330 175 7:1 291
30 290 10:1 348 190 6:1 315
40 320 8:1 384 220 6:1 365
50 350 7:1 420 250 5:1 415
60 380 6:1 456 280 5:1 465
70 410 6:1 492 310 4:1 515
80 440 6:1 528 340 4:1 564
90 470 5:1 564 370 4:1 614
100 500 5:1 600 400 4:1 664
110 530 5:1 636 430 4:1 714
120 560 5:1 672 460 4:1 764
130 590 5:1 708 490 4:1 813
140 620 4:1 744 520 4:1 863
150 650 4:1 780 550 4:1 913
Max Chain 300 300
Max Depth 30 60
Total Weight 360 498

 



 
Last modified: December 31 1969 19:00