时间:2011-04-05 11:32来源:蓝天飞行翻译 作者:航空 点击:次
To view this page ensure that Adobe Flash Player version 9.0.124 or greater is installed. WINDS Wind direction and velocity also affect hovering, takeoff, and climb performance. Translational lift occurs anytime there is relative airflow over the rotor disc. This occurs whether the relative airflow is caused by helicopter movement or by the wind. As wind speed increases, translational lift increases, resulting in less power required to hover. The wind direction is also an important consideration. Headwinds are the most desirable as they contribute to the most increase in performance. Strong crosswinds Approximate Density Altitude – Thousands of Feet
13 12 Conversion� Factor 11 30.4� -440� 30.5� -531� 30.6� -622� °C SL -18 -12-7 -1 4 1016212732 30.7� -712� 30.8� -803� °F 0 10 20 30 40 50 60 and tailwinds may require the use of more tail rotor thrust to maintain directional control. This increased tail rotor thrust absorbs power from the engine, which means there is less power available to the main rotor for the production of lift. Some helicopters even have a critical wind azimuth or maximum safe relative wind chart. Operating the helicopter beyond these limits could cause loss of tail rotor effectiveness. PERFORMANCE CHARTS |