ventral fin


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ventral fin

ventral fin
A vertical, stabilizing fin on the lower rear portion of a fuselage that helps increase directional stability, especially at higher Mach numbers, by increasing the area behind the vertical axis.
References in periodicals archive ?
Sexual dimorphism: Males are smaller than females with proportionally longer pectoral, anal and ventral fins.
Ventral fins are inserted from more posterior part in females than those in males.
Alestes nurse had 10 dorsal fins, 14 anal fins, 31 caudal fins, 7 pectoral fins and 6 ventral fins Table 3 (D9).
The pilot tried to keep the air craft flying but the ventral fins contacted the runway making further rotation impossible.
chrysospilos has ventral fins displaced forwards, underneath the pectoral fins, and joined at their base in a type of sucker that lets them climb up the roots and trunks of the trees of the mangrove swamp.
Body ovoid in dorsal view, widest at about level of eyes, wider than high, depressed in lateral view, higher posteriorly than anteriorly; neuromasts visible; snout rounded in dorsal and lateral views; eyes moderate in size, round, situated dorsolaterally; nostrils slit-shaped, directed anteriorly, closer to eye than tip of snout; spiracle sinistral, forming round aperture; vent tube dextral; caudal musculature robust, highest at base, gradually tapering to pointed tip; caudal fin tip rounded; dorsal and ventral fins of nearly equal height throughout their lengths.
7); scales immediately behind pectoral origin cycloid, but becoming more strongly ctenoid posteriorly; scales on caudal peduncle strongly ctenoid; scales on chest laterally and ventrally strongly ctenoid; large interpelvic scale present; scales on belly weakly ctenoid, about 1/3 smaller than flank scales and imbricating; scales on anal-genital region of similar size to flank scales, weakly to strongly ctenoid; scales on caudal cycloid, arranged in single row between and along rays; two scale rows between upper and lower lateral line, rostrally and caudally; four scale rows between upper lateral line and base of dorsal; four scale rows between bases of pectoral and ventral fins.