| 摘要 |
FIELD: commercial fishery technique. ^ SUBSTANCE: otter board has lower wing, upper wing and at least one intermediate wing, said wings being curved in direction of advancement of otter board in water so as to define channels therebetween, parallel longitudinal fins and keel. Wings are made of different length and are stepped one above another with different gaps therebetween so as to define V-shaped profile relative to central longitudinal fin. Wings have aerodynamic profile with maximum profile of upper wing making 18% of wing length, and wing length to wing width ratio constituting from about 1:1.3 to about 1:1.4. Angle of V-shaped profile is 155 deg. Fins have unequal arms. Wing front edges are reinforced with stringers. At least one additional guiding and stabilizing fin is provided along the entire length of otter board wings and four additional guiding and stabilizing fins are provided along the entire length of otter board. ^ EFFECT: increased efficiency, enhanced reliability in operation and reduced consumption of power by increased thrust force, reduced draft, increased vertical stability of otter board at any fish catching depth and substantial angles of attack, and wide range of trawling velocity, reduced overturning tendency and decreased linear sizes of otter board. ^ 8 cl, 4 dwg |
