Flight Number: 970205H1 Page 1 of
Date: February 6, 1997 Aircraft ID: 42RF Scientist: Jorgensen
Event Log
Time Approx. Location Event & Comments (UTC) (Lat, Lon) 20:40:11 Shannon Engine Start 20:42:30 Shannon Block out This is mission 7 and IOP11. Mission is LOW 30. Will perform coordinated runs with UK C-130 near low center 20:54:02 52.709 -8.910 Take off 21:07:49 53.170 -9.790 radars are up 21:17:14 53.567 -10.512 contact with METMAN 21:51:16 TA apparently not working correctly - techs working on it 21:54:53 55.366 -13.348 in extensive stratiform percip - mostly below 5 km. See bright band about 1 km above sfc 21:55:59 55.426 -13.433 begin descent to 5 kft about 40 km from buoy 21:58:46 begin recording radar data-TA still being worked on 22:02:18 55.821 -13.975 at 5k ft-tracking toward the buoy 22:06:42 contact with 308D-they are still hunting for a good band to work-we are in extensive stratiform precip with a strong bright band 22:07:48 55.980 -14.445 now tracking 255 to the storm center 22:09:49 TA now apparently up and running 22:17:26 55.861 -15.355 curved bands of precip 22:21:59 55.816 -15.757 climbing up 1000 ft to get on top of the shear layer 22:27:05 55.762 -16.162 temps about 2 degrees warmer at 6k ft than at 5k ft - turbulence much reduced too-may have cross on top of the front 22:34:03 55.703 -16.705 more cellular precip as we proceed WSW 22:51:15 TA malfunctioning again radial velocities look bad 23:00:25 55.424 -18.776 curved bands 200-300 km to the north 23:03:40 G-IV apparently entered the box at the same altitude as METMAN. The C-C-130 descended to 24k ft 23:09:55 contact with METMAN 23:13:55 techs will try to replace the Doppler signal processor 23:25:17 55.122 -20.779 radar system down as the DSP is replaced 23:25:44 55.115 -20.822 banded features to the NW might be cold front or bent back region 23:29:38 55.068 -21.139 sfc pressures continue to fall as we get close to the trough axis 23:47:47 54.818 -22.688 can't get far enough west to go through the front - turning to track to our IP with METMAN 23:49:59 TA seems to be working better 23:51:17 55.007 -22.672 now tracking 020 toward pt 1 0:00:21 55.643 -22.308 descending back down to 5k ft position report from 49: 54 44N 23 38W 0:10:04 56.214 -21.976 apparently through the front at this level as the winds have shifted to the north and temps have dropped to -4.2C 0:12:55 apparently 308D is heading back 0:31:47 57.401 -21.239 still in extensive stratiform precip-cold front well marked on LF as band to our SE. 0:32:45 57.457 -21.202 at IP starting leg 1 with METMAN 0:44:41 57.050 -20.073 cloud deck coming down on TA - temps warming a few degrees and winds shifting to SW 0:49:27 56.874 -19.641 more turbulent as we move into the warm side - more convective type cells evident on TA 0:52:07 56.773 -19.396 pronounced slope to the echoes on the TA from S to N 1:01:28 56.410 -18.551 winds now up to 70 knots from 225 as we move into the warmer air on the SE side of the front 1:03:34 METMAN reports sonde system failure, most of the sondes on this run may be lost 1:12:13 55.979 -17.598 going through a field of shallow convective type cells 1:19:07 55.695 -16.984 going down to 1000 ft to check out the low level jet strength 1:23:49 55.509 -16.605 at bottom of descet-climb up to 8 kft 1:26:05 55.444 -16.719 out of the turbulent boundary layer at1000 m altitude (RA) 1:28:48 55.365 -16.878 now tracking 231 to point 3 end of leg 1 1:40:49 55.051 -17.631 at pt 3 turn to track 333 to pt 4 start of leg 2 1:43:03 METMAN reports its turn to the NW at 0131 1:50:11 55.645 -18.133 cold front curves to the east north of us - becoming a warm front with wave development near us? 1:54:14 55.903 -18.351 some increase in turbulence 1:55:08 55.963 -18.402 back to calmer air 1:57:30 56.106 -18.535 entering stratiform precip 2:04:45 56.565 -18.945 very strong bright band now up to 35 dBZ 2:13:47 56.565 -18.945 precip decreasing in intensity 2:16:25 57.298 -19.637 there has been a change in the orientation of the sea clutter from a maximum to the south to a maximum to the north - change in sfc winds reflecting strong northerlies behind the front? 2:17:41 57.375 -19.708 winds dropping off rapidly now 2:20:20 57.534 -19.856 small line line on LF immediaately ahead 5 nm 2:30:45 58.161 -20.462 extended the leg slightly to go through the narrow thin reflectivity line 2:31:23 58.183 -20.521 end of the leg - turning to track 205 to pt 5 2:33:09 58.087 -20.625 never did get into the cold air at 8k ft 2:42:28 57.525 -21.083 end of cross leg at pt 5-trk 132 on leg 3 2:47:35 57.311 -20.616 winds now backing around to SW-wind speed now increasing too-very light stratiform precip 3:01:38 56.761 -19.252 going through small band-looks fairly stratiform on TA 3:03:31 56.683 -19.071 sfc position of the front is apparently marked by a sea clutter minimum 3:12:20 56.326 -18.229 through the last weak band indicating we're into the warm side of the sfc position of the front. Descending to 1000 ft in a mini-sounding to map the low level jet 3:15:08 56.216 -17.981 now in precip free region 3:20:39 56.009 -17.533 at 1000 ft in turbulent air - climbing back up to 5k ft. Low level jet max of 75 knots at 3000 ft. Decreasing below 3:25:00 55.851 -17.184 cutting this leg a little short to save a little time. End of Leg 3. Turn to trk 255 to new pt. 7 3:28:20 at 5k ft for rest of run 3:29:37 wind direction and the track are the same. Every bit of the 72 knot wind is in our face 3:41:33 now trk 337 start of leg 4 3:52:25 56.250 -18.685 most turbulence so far as we go through the front for the last time 3:54:08 56.360 -18.777 entering frontal precip zone 4:01:31 56.820 -19.157 turbulence decreasing as we apparantly moved through the narrow cold front band 4:22:45 57.966 -20.142 at the final end point-extending the leg 20 nm farther NW to examine secondary band of precip 4:29:26 58.328 -20.453 end of leg, climb to 15k ft for trek to buoy-the extra altitude is for fuel economy 4:30:32 58.357 -20.366 still in light stratiform precip 4:36:53 58.122 -19.668 the frontal width is well marked by the lack of ground return-approximately 20 nm wide 4:51:38 radar system locked up for a few minutes at 0445 Z 4:52:46 57.465 -17.936 getting into heavier stratiform precip as we move to the south-bright band is well defined and >30 dBZ in spots 4:58:17 57.226 -17.342 precip decreasing rapidly over buoy at 15k ft 6:21:04 53.176 -9.724 begin descent 6:40:06 SNN land 6:45:40 SNN block in