¡§Flight Recorders Lab¡¨ was set up by Aviation Safety Council¡]ASC¡^ in 1999 and changed it¡¦s name to ¡§Investigation Lab¡¨ in May, 2001. The majorities of investigation lab are:
(1) Develop flight recorders read-out techniques
(2) Develop the time synchronization processing of flight data to reconstruct the operation situation ¡]Voice and flight data¡^of the flight crew.
(3) Develop site-survey technique: integrate DGPS¡]Differential Global Positioning System¡^ and Laser Ranger.
(4) Integrate digital Map and flight animation system to integrate flight data and site-survey information to recovery the history and environment of the accident
(5) Develop 3-D software wreckage scanning system to model and assemble pieces of wreckage.
(6) Develop CVR¡]Cockpit Voice Recorder¡^spectrum analysis to identify the power instrument failure, flight crew reaction and the warning signal in the cockpit.
(7) Develop aircraft flight track and performance calculation
(8) Develop E-management software and investigation database
Under the past 6 years¡¦ efforts , ASC could integrate and display the investigation information, such as flight data, flight track reconstruction, aircraft performance and site-survey data, into GIS¡]Geographic Information System¡^and Flight Animation System¡]FAS¡^. The MapInfo, a kind of GIS software, is used by ASC to integrate the site-survey data, including DGPS and Laser Ranger. In addition, ASC also superposition the following digital mapping layers, such as Air Route, Airport diagram, flight track, terrain, to assist accident investigation. The GIS system is widely use in the CI611 accident by superposition the radar track and suspect underwater target to assist to do wreckage recovery.
¡]1¡^
Flight data read-out and flight animation
The reconstruction of the flight track, according to the history of flight, was not only used in the engineer analysis, but also could be displayed to the investigation team or publics. After read-our and analysis flight data, ASC Investigation Lab synchronizes the flight data with the voice of CVR¡]Cockpit Voice Recorder¡^, and then combines with cockpit instruments, and digital map to make the 3-D animation realistically.
¡]2¡^
Site-Survey and GIS Display System
ASC Investigation Lab using GPS and Laser Ranger as site-survey measurement instruments to meet the variety and emergency of the accident site survey. The GPS equipments including hand-held¡]Low accuracy¡^ and shouldered type¡]high accuracy¡^. After differential, the accuracy of GPS could be approximated to 20cm.and the accuracy of Laser Ranger is 0.5cm. Besides these, we also using 3-D scanner to build up the 3-D model ¡]terrain, tree, building¡Ketc¡^of the accident scene.
Then, the on scene information will be integrated with satellite image, aerophoto, and DTM¡]Digital Terrain Model¡^to show the relation between wreckage, flight track, terrain and some important landmarks.
¡]3¡^
Cockpit Voice Spectrum analysis
Cockpit voice recorders, recording the crew¡¦s communication voice and operation sounds in the cockpit, are important evidences in the investigation process. Because some of the voices are hard to distinguish or heard by human, the spectrum and energy analysis could be adopted by ASC Investigation Lab to identify the source, starting and lasting time, or some specific voice of warning activation in the cockpit. In this way, this technology is very helpful to identify the voice, power failure analysis, whether the aircraft explosive in the air or not.
The following picture depicts that spectrum analysis of the voice, recorded by the videotape, is used to identify the power failure of the helicopter, happened in the
Tainan.
¡]4¡^
Aircraft Flight Track and Performance Calculation
In order to obtain the flight path rapidly and accurately, ASC Investigation Lab develop the program, Flight Path Reconstruction System¡]FPRS¡^, to superposition the GIS related layers. Now, the FPRS has trajectory calculation function, including Primary Radar, Secondary Radar, and FDR parameters.
ASC Investigation Lab develops aircraft performance calculations techniques by themselves and academic units. The performance analysis could provide the investigation team members about the engineering analysis results. Nowadays, ASC Investigation Lab has developed the wind field estimation, wind-shear identification via load-factor, trajectory estimation, aircraft take-off runway length and friction coefficient estimation, lift and drag coefficient of aircraft estimation, aircraft icing performance analysis, and aircraft stability analysis.
¡]5¡^
3-D Software Reconstruction and Presentation System
After CI611 accident, ASC decides to develop 3-D reconstruction technique by software in a short time. The project is called 3-D Software Wreckage Reconstruction and Presentation System, 3D-SWRPS. This project will be used in 3-D software reconstruction for CI611 to assist the hardware reconstruction and analysis phase in investigation.
The main tasks on this project are: (1) co-operate with hardware reconstruction to provide the investigation team about the un-recovered wreckage configuration and through the damaged outline of the wreckage to do force analysis. (2) Integrate the flight track, primary radar return signal, and wreckage recovery information to simulate and find the break-up sequence of the airplane.
(6)
Accident Investigation schedule management system
The accident investigation schedule management system ¡]AISMS¡^, according to the accident investigation procedures for ASC, provides the investigation members an e-environment through net work to arrange and manage the progress, the members of the group, man power, reports of the investigation. There are three majorities of the system:
(1) Notification: After setting up the stage and member of the investigation, the system could send the latest information automatically through e-mail, such as new factual data, schedule, and IIC¡¦s notification to the investigation team via e-mail.
(2) Report updates: The investigation data could update to the file.
(3) Reminding: The system could send the e-mail to the member to remind them the deadline of the scheduled investigation reports.
(7)
CI-611 factual information management system
CI611 investigation database tries to collect and integrate on scene data and provide the investigator about graphical user-friendly interface via Internet to query and analyze. The database contains five subsystems: wreckage management subsystem, documents of injury pattern for victims, maintenance documents subsystem, Reports of each investigation group, and
administrator.
In order to be user-friendly, there are three GUI interfaces provide to the user: wreckages geographic query interface¡]using GIS layers¡¦ concept¡^, seats and injury patterns of the victims query interface, and aircraft station/section selection interface. All of the GUI interfaces are developed by java. If the query results have latitude and longitude information, the results could be output as *.mif format. In this way, the user could use free GIS browser to review the query results in their own computer.
¡@
Aviation Safety Council Privacy and Security Policy Tel:
886-2-8912-7388 Fax: 886-2-8912-7399 Address: 11F., No.200,
Sec. 3, Beisin Rd., Sindian City, Taipei County 231, Taiwan (R.O.C.)
![(open new window) DTFAS¡]Digital Terrain and Flight Animation System¡^](pic_view.asp?picname=lab_l_4.jpg)
![(open new window) Site-Survey results¡]out of runway in Kingman¡^](pic_view.asp?picname=lab_l_6.jpg)
![Take-off Performance analysis¡]hit the runway end light during take off¡^](images/lab_s_9.jpg)
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