Summary of LEAR 36 FLIGHT #1 Monday 11/1/97 from St. John's, Newfoundland (YYT: 47.5N, 53W) all locations, altitudes, winds & temperatures are from controls & GPS in airplane cockpit (i.e. pressure altimeter), not from dropsondes. all information is approximate. NOTE: all winds for this flight are magnetic, not true. to approximate true winds, subtract 20deg. takeoff: 12:45 Z from YYT (scheduled for 10:15 Z, 6:45 local time. 0:15 delay due to fog, 2:15 refuelling delay) landing: 17:50 Z at YYT flight time: approx. 5 h 5 min pre-flight: fog, ice pellets, freezing rain, snow (in that order). during flight: no noteworthy weather, 30-100% cloud cover below flight level. pilot: George Kickhofel (Flight International) co-pilot & navigator: Gordon Stevenson ( " ) crew #1 (on board scientist): Rebecca Morss (MIT) crew #2 (dropsonde operator): Dean Lauritsen (NCAR) crew #3 (units conversion officer): Bruce Morley (NCAR) planned flight path: YYT -> 45N 52W, time of arrival = before 12Z -> 45N 40W (leg 2) -> 54N 40W (leg 3) -> YYT (leg 4) drop ~ 12 sondes, at corners & 3 on each of legs 2-4 DROPSONDES: it takes an avg. of 30 seconds after launch for sonde to begin tracking satellites & obtain wind data (using GPS). several sondes took much longer to obtain winds; thermodynamic data was still recorded in these cases. leg 1: short. cleared to 41000 ft for 1st drop before 1st turn, within radar contact (had difficulty reaching 41000 ft) 1. 13:07 Z 44.9N, 51.7W 38000 ft = 11.6 km = 207 mb T=-51C winds from 183deg at 166 knots = 83 m/s near launch location thought launch was from 41000 ft. sonde slow to obtain wind data. leg 2: cleared down to 31000 ft after turn (exiting radar area). descended. 2. 13:15 Z 48.8N, 45.0W 31000 ft = 9.4 km = 291 mb -51C 183deg at 166 knots = 83 m/s thought launch was from 35000 ft. sonde slow to obtain wind data. 3. 13:33 Z 45.1N, 46.0W 31000 ft -42C 290deg at 170 kn = 85 m/s got the launch altitude correct this time! crew rejoices. 4. 13:46 Z 45.1N, 43.0W 31000 ft -43C 299deg at 168 kn = 84 m/s cleared down to 27000 ft before turn. descended. 5. 14:01 Z 45.0N, 39.9W 27000 ft -34C 325deg at 119 kn = 60 m/s lost some of signal from sonde due to bank of airplane during turn after launch. in future, should launch after turn if possible. leg 3: 6. 14:25 Z 47.2N, 40.0W 27000 ft -34C 284deg at 108 kn = 54 m/s 7. 14:47 Z 49.5N, 40.0W 27000 ft -40C 287deg at 86 kn = 43 m/s 8. 15:09 Z 51.7N, 40.0W 27000 ft -43C 285deg at 100 kn = 50 m/s 9. 15:32 Z 53.9N, 40.0W 27000 ft -42C 297deg at 78 kn = 39 m/s leg 4: 10. 15:58 Z 52.7N, 43.3W 27000 ft -43C 235deg at 74 kn = 37 m/s 11. 16:23 Z 51.2N, 46.6W 27000 ft -44C 151deg at 108 kn = 54 m/s 12. 16:49 Z 49.5N, 49.6W 27000 ft -41C 200deg at 58 kn = 29 m/s sonde launched just after turn. back to St. John's: sunny (finally) and windy.