Tham khảo tài liệu 'kỹ thuật máy bay chiến đấu episode 2 part 9', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 436 AIRCRAFT DESIGN Af 2VWing 7VW8flồa Mus Fv Xacv A cg TYp DYp -FptX x-Xp L LV iai LVờaòa F ZV These yaw and roll moments are summed in Eqs. and for a twin-engined aircraft with one engine out. Similar equations for other engine arrangements should be obvious from inspection of Fig. . These are strictly static equations. Dynamic terms will be considered in a later section. The lateral lift force on the vertical tail appears in both equations. This is much like the horizontal-tail lift and must be calculated using the local dynamic pressure and angle of sideslip. The local angle of sideslip is less than the freestream sideslip angle because of a sidewash effect largely due to the fuselage. Propwash can also reduce the effective angle of sideslip. Equation expresses the lateral lift force on the vertical tail. Note that the tail lateral-lift-force derivative CFf is equivalent to CLa in longitudinal notation and is calculated the same way. F q CFfit i The yaw- and roll-moment equations are expressed in coefficient form by dividing through by qSJ as shown in Eqs. and . Lengths are expressed Jis a fraction of wing span using the bar notation. Thus Y denotes Y b . The ratio between dynamic pressure at the tail and the freestream dynamic pressure is denoted by 1ỊV. The vertical-tail contributions to yaw and roll are expressed by the derivatives defined in Eqs. and . Yaw where c qSwb Cn0 p C oôữ J3 qSw qSw qSw Ci p ft Sv z Y Y X n0v dp sw Roll Ct qSJ where c. c ỀỀv Sy 7 Vv s STABILITY CONTROL AND HANDLING QUALITIES 437 Lateral-Trim Analysis The main static lateral-trim condition of concern is the engine-out case on takeoff. The vertical tail with rudder deflected must produce sufficient yawing moment to keep the aircraft at zero angle of sideslip at takeoff speed times the stall speed with one engine out and at the aftmost . location. Rudder deflection should probably be no .
