NITRO 31: ORC Rating

GPH

548.2

OSN

531.3

LOA

9.573 m

Displacement

1840 kg

Triple-Number Ratings

Lower is faster

Triple Inshore

Low

0.7474

Medium

0.9864

High

1.1717

Triple Offshore

Low

0.9558

Medium

1.2276

High

1.4382

Boat Specifications

Dimensions

Length overall: 9.573 m
Beam: 3.05 m
Draft: 2.45 m
Displacement: 1840 kg
Crew weight: 595 kg
Wetted surface: 20.61 m²

Sails

Mainsail: 37.91 m²
Genoa: 24.17 m²
Spinnaker: 0 m²
Asymmetric spinnaker: 116.64 m²

Design

Type: Cape 31
Builder: Noordhoek
Designer: Mills
Year built: 2017

Performance data

Polar CSV

Each row is TWS followed by TWA and boat-speed pairs. Paste it directly into Offwind or compatible navigation software.

6,42.3,5.421622,52,6.05,60,6.34,75,6.53,90,6.38,110,6.47,120,6.34,135,5.62,142.3,5.169209,150,4.72
8,39.7,6.303617,52,7.03,60,7.23,75,7.36,90,7.29,110,7.58,120,7.51,135,7.05,145.6,6.314283,150,6.01
10,38,6.675036,52,7.48,60,7.78,75,8.08,90,8,110,8.37,120,8.52,135,8.01,148.9,7.123945,150,7.05
12,37.1,6.845675,52,7.72,60,8.08,75,8.62,90,8.82,110,8.93,120,9.35,135,9.09,149.4,8.004721,150,7.96
14,36.6,6.938065,52,7.9,60,8.3,75,8.94,90,9.5,110,9.46,120,10.01,135,10.37,146.2,9.278152,150,8.9
16,36.3,7.022957,52,8.05,60,8.47,75,9.21,90,9.94,110,9.97,120,10.66,135,11.64,145.2,10.594908,150,10.05
20,36.3,7.13463,52,8.24,60,8.71,75,9.6,90,10.65,110,11.73,120,11.91,135,13.55,144.5,14.138043,150,13.28
24,37,7.124652,52,8.24,60,8.76,75,9.8,90,11.14,110,13.05,120,13.4,135,15.48,149.2,16.869239,150,16.73

Wind Speed	52°	60°	75°	90°	110°	120°	135°	150°
6	6.05	6.34	6.53	6.38	6.47	6.34	5.62	4.72
8	7.03	7.23	7.36	7.29	7.58	7.51	7.05	6.01
10	7.48	7.78	8.08	8	8.37	8.52	8.01	7.05
12	7.72	8.08	8.62	8.82	8.93	9.35	9.09	7.96
14	7.9	8.3	8.94	9.5	9.46	10.01	10.37	8.9
16	8.05	8.47	9.21	9.94	9.97	10.66	11.64	10.05
20	8.24	8.71	9.6	10.65	11.73	11.91	13.55	13.28
24	8.24	8.76	9.8	11.14	13.05	13.4	15.48	16.73

Wind Speed	Beat Angle	Beat VMG	Run Angle	Run VMG
6	42.3°	4.01	142.3°	4.09
8	39.7°	4.85	145.6°	5.21
10	38°	5.26	148.9°	6.1
12	37.1°	5.46	149.4°	6.89
14	36.6°	5.57	146.2°	7.71
16	36.3°	5.66	145.2°	8.7
20	36.3°	5.75	144.5°	11.51
24	37°	5.69	149.2°	14.49

VPP POLAR · BOAT SPEED BY TWAKT

TRUE WIND ANGLE —

READ AT ANGLE

Hover or tap the chart, or use the slider, to read boat speeds.

True wind speed 6 kt8 kt10 kt12 kt14 kt16 kt20 kt24 kt

Data table

Boat speed by true wind angle and true wind speed
TWA	Boat speed in 6 kt (kt)	Boat speed in 8 kt (kt)	Boat speed in 10 kt (kt)	Boat speed in 12 kt (kt)	Boat speed in 14 kt (kt)	Boat speed in 16 kt (kt)	Boat speed in 20 kt (kt)	Boat speed in 24 kt (kt)
0°	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
52°	6.05	7.03	7.48	7.72	7.90	8.05	8.24	8.24
60°	6.34	7.23	7.78	8.08	8.30	8.47	8.71	8.76
75°	6.53	7.36	8.08	8.62	8.94	9.21	9.60	9.80
90°	6.38	7.29	8.00	8.82	9.50	9.94	10.65	11.14
110°	6.47	7.58	8.37	8.93	9.46	9.97	11.73	13.05
120°	6.34	7.51	8.52	9.35	10.01	10.66	11.91	13.40
135°	5.62	7.05	8.01	9.09	10.37	11.64	13.55	15.48
150°	4.72	6.01	7.05	7.96	8.90	10.05	13.28	16.73