臺北飛航情報區現地空載亂流觀測

Abstract

亂流一直都是影響航空安全的重點因素之一。過去我們仰賴飛行員報告（PIREPs）來記錄航行過程中所遭遇的亂流事件時間、位置與強度。隨著時間的演進，這樣的觀測方法對於目前的數值模式預報來說，在時空的精確度與強度的定量上略顯不足。因此一個描述大氣亂流的定量指標——渦流消散速率（Eddy Dissipation Rate，EDR）被國際民用航空組織（International Civil Aviation Organization，ICAO）提出。這個指標具有和機型無關的特性，因此適合做為一個定量的標準數值來將大氣中的亂流進行量化。不過部分現有之EDR演算法所需要的變數，必須透過航空公司從飛行電腦當中下載，因此對於資料的取得不易。 本研究旨在開發一套低成本且易攜帶的現地機載亂流觀測盒（In-Situ Airborne Turbulence Box，ISATB），透過重新組裝無人機模組，並結合公開的ADS-B/Mode-S資料，本研究實現了以易取得的方法計算航路上之EDR數值。該觀測儀器已被我們攜帶搭乘不同航班，包括國內低高度航班與國際越洋航線，並成功通過安檢，且觀測儀器自帶記憶卡，僅需額外接上行動電源即可實時紀錄航空器擾動的定量資料。 經過20多次航班個案，本研究成功利用自製觀測儀器對亂流事件進行量測，並與觀測人員的感受紀錄進行比對，證實了觀測儀器的準確性和可靠性。觀測結果顯示，觀測儀器對不同強度的亂流事件有著良好的反應，能夠準確記錄亂流事件發生的時間和地點，與人員觀測結果高度一致。此外，本文針對三種不同天氣型態，共五個個案討論的綜合比對，將觀測儀器與臺灣民用航空局臺北航空氣象中心現有之美國國家大氣研究中心（National Center for Atmospheric Research，NCAR）亂流數值預報產品進行比對，ISATB對不同強度的亂流事件有著一定的分辨能力，能夠區分不同強度的亂流，進一步豐富了航空亂流觀測的資料庫。

Turbulence has been a critical factor affecting aviation safety. Traditionally, Pilot Reports (PIREPs) have been used to record the time, location, and intensity of turbulence encounters during flights. However, as numerical forecasting models have advanced, this method has shown limitations in spatial and temporal precision and in accurately quantifying turbulence intensity. To address these shortcomings, the Eddy Dissipation Rate (EDR) has been introduced as a quantitative indicator for describing atmospheric turbulence by International Civil Aviation Organization (ICAO). EDR is independent of aircraft type, making it suitable as a standardized metric for quantifying turbulence in the atmosphere. Nonetheless, some existing EDR algorithms require variables that can only be obtained through data downloads from aircraft flight computers, which restricts data accessibility. This study aims to develop a low-cost and portable in-situ airborne turbulence box (ISATB) by reassembling drone modules and integrating public ADS-B/Mode-S data. By utilizing this method, the study successfully calculated EDR values along flight routes using readily accessible means. The observational instrument has been carried on various domestic and international flights. It has successfully passed security checks and is equipped with a memory card, requiring only an external power bank to aircraft turbulence data in real time. Through more than 20 flight cases, the study effectively measured turbulence events using the self-designed observational instrument. Comparisons with observers' subjective records verified the instrument's accuracy and reliability. The results indicate that the instrument responds well to turbulence events of varying intensities, accurately recording the time and location of such events, which were highly consistent with human observations. Furthermore, based on the comprehensive comparison of three different weather patterns and a total of five cases, the observation instruments were compared with the existing turbulence numerical forecast products from the National Center for Atmospheric Research (NCAR) provided by the Taipei Aeronautical Meteorological Center of the Civil Aviation Administration of Taiwan. This capability enhances the existing turbulence observation database and improves our understanding of turbulence prediction.