當飛行經過亂流區域時，相對速度、攻角、力矩…等各項數值均產生變化，對航機飛行安全造成危害，尤其是晴空亂流，現役客機之機載裝備無法偵測，駕駛員能獲得之反應時間很短，易造成飛安事故。
現行國際民航組織（ICAO）、美國國家運輸安全委員會（NTSB）、飛機製造商及學術界發展以垂直加速度、渦流消散率及垂直風擾動等瞬時及均方根值判斷亂流強度估算方式，本研究以飛航紀錄器所紀錄各項數據，依垂直加速度均方根變化判別亂流等級外，經座標軸轉換、運用擴展式卡爾曼濾波器及力平衡方程式估算，分析航機穿越亂流時之氣動力參數變化及靜態穩定率。
經由擴展式卡爾曼濾波器調整後之飛航參數，可以有效估算氣動力參數，針對航機遭遇亂流期間氣動力參數變化劇烈現象，應按照飛行手冊減速穿越亂流，避免航機因昇力劇烈的變化，造成飛機的損傷或危及人員的安全。

The velocity, angle of attack, and moment of the aircraft change intensely when an aircraft flies under the influence of turbulence, and hence it may causes dangerous in flight. For Clear Air Turbulence (CAT), it is difficult for current equipments on aircrafts to detect the turbulence, so the pilot can not get sufficient time to react and sometimes may cause accidents. International Civil Aviation Organization (ICAO) and National Transportation Safety Board (NTSB) have developed three basic methods of Eddy Dissipation Rate (EDR), vertical wind perturbation, and RMS of vertical acceleration, to measure turbulence intensity.

In this research, a set of data under the influence of turbulence from the Flight Data Recorder (FDR) has been analyzed. Firstly, the data have been transformed into the desired coordinate system. Secondly, Extended Kalman Filter (EKF) has been applied with suitable governing equations and flight conditions to estimate aerodynamic parameters and the static stability derivatives. In addition, the Root Mean Square (RMS) method has been used to indicate the degree of parameter variation and hence the strength of turbulence.

The results show that the Extended Kalman Filter can effectively estimate the wind and aerodynamic parameters. The aerodynamic parameters change rapidly under turbulence influence. The RMS method can suitably reflect the strength of turbulence. The studied case was really under a severe turbulence flight condition.

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[14] FLUG REVUE Datafile：Airbus A330-203
http://www.flug-revue.rotor.com/FRTypen/FRA33020.htm