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Navigation Data

Navigation files were extracted as a tab-delimited American Standard Code for Information Interchange (ASCII) text file from a Garmin GPSMAP 196. For each trackpoint, the Garmin GPSMAP 196 recorded the following: latitude, longitude, date/time, altitude, depth, leg length, leg time, leg speed, and leg course.

The images were acquired using a Canon EOS 5D Mark III. The camera was synchronized to UTC and the time of capture was recorded in the Exchangeable Image File (EXIF) header of each image. Image files were named according to the time they were captured. The image filenames have the format yyyy_mmdd_hhmmssd.jpg. (For example, image 2015_0918_133636d.jpg was taken September 18, 2015, at 13:36:36 Coordinated Universal Time (UTC), and "d" designates that a digital camera was used.) Images are associated with GPS positions according to the time of capture. Google Earth is used to view selected images taken during the flight based on their time of capture compared with the recorded position of the aircraft at that time in the GPS record.

Processed Navigation

The processed navigation file can be accessed from within the nav folder or by clicking the following link to the comma-separated value (CSV) file: ds1008_2015-335-FA.csv (CSV file). The file contains 12 fields that are defined as follows:

Raw Navigation

The raw navigation files can be accessed from within the nav folder or by clicking the following link to the text file (TXT) file: ds1008_2015-335-FA_0918_gpsmap196.txt (text file). The file contains nine fields (separated by spaces) that are defined as follows:

Field 1: HEADER: "Trackpoint"
Field 2: POSITION: latitude (N (North) degrees, decimal minutes), longitude (W (West) degrees, decimal minutes) position of aircraft
Field 3: TIME: date and time (m/d/yyyy hh:mm:ss am/pm)
Field 4: ALTITUDE (feet)
Field 5: DEPTH: blank
Field 6: LEG LENGTH (feet)
Field 7: LEG TIME (hh:mm:ss)
Field 8: LEG SPEED (mph)
Field 9: LEG COURSE (degrees "true")