INDOEX C-130:  FLIGHT 13, 16 March 1999

Mission Scientists:  Gandrud and Roca

Flight started out to examine clouds in polluted airmass to the N-NW of
Male.  Intercepted some low clouds on the outbound legs but the clouds next
to Indian coast disappeared by the time we got there.  Used the flight time
to look at vertical profiles in this very heavily polluted haze layer very
close to Indian coastline with clear skies above the haze.  Dropped sondes
over KCO and Male on the return to the airport and then a long slow descent
into the airport for a contrast with the earlier polluted haze layer.

UTC
02:26   Taxiing; low cloud around Hulule (some Cu towers up to 2 km), faint Ci
02:28   Visibility quite good
02:30   Take-off, climb to 5Kft en route to 9N & 66.5E
02:40   4.7N & 73.1E, 4720ft, clear sky and Ci above and in front of us.
         Hazy horizon; some nice st cu beneath
02:45   Very isolated st cu below
02:50   Haze below quite thick in the first 1.5 km., @ 5000ft we are above.
02:55   CN increase in the haze
03:00   Plenty of st cu below us, looks very good; winds are to SW
03:03   Started descent to 1500 ft, Some st cu south of us.
         No ci to the South some (thin & thick) to the N
03:05   In the haze; 2200ft very thick; vis 3-4 minutes in front; 6.24N & 71.9E
03:10   The first cloud was entered.
03:11   One band in sight at our level
03:15   Hit the cloud band 6.48N 71.72E & 2000ft, a good 5 minutes leg.,
         S slight Ci. N Ci above
03:21   Entering cloud @ 6.5N & 71.7E
03:23   Starting to see cirrus to N & ahead
03:25   Another cloud band; St cu (200m) thick, pretty active.
03:35   Alternate low & clear dirty 10% in cloud time.  7.25N & 71.1E
03:37   SABL reports we are in haze layer w/ top of HL @ 8Kft
03:45   Same conditions st cu band after st cu band 7.6N & 70.58E, 2500ft.
         Density of clouds increases S & N.  Ci above.  Clouds rather Cu
         than st, thicker than before.
03:47   Slight alt change to stay in clouds
03:55   Cloud density still increasing 7.83N & 70.00E.  N Ci & S Ci
03:56   Call Ops center.  Plenty of st cu 2700 ft.  Sat update.
         The target cloud NE close to India still there.
03:57   Another alt change to stay in clouds
04:10   Below the cloud leg 2300 ft (Pilot fixes the fwd video camera,
         bug in view)
04:11   Descend to 500ft to get below clouds
04:20   2300ft 5 more min then at the cloud level
04:26   Climb back to cloud level at 2600ft or so
04:35   8.6N & 67.6E; Ci above, st cu band
04:45   Cloud band 8.8N & 67.3E high density of clouds
04:50   About to head NE 8.94N & 67.08E in the cloud band.  High density of
         clouds hazy horizon.
04:51   Turn at 9N & 67E to new heading, 14N & 71E, clouds shortly after turn
05:10   Clouds with cirrus overhead
05:15   Satcom says S end of cloud is 15N & 72E, N end is 17N & 71E
05:25   See air mass change w/ low water, higher T & lower CN
05:43   Subsidence area has plenty of cirrus above
05:47   Still in subsidence area. Ci above
05:50   11.6N & 69.1E.  No low cloud, some Ci above
06:00   Descend to 500ftfor 15 min sample, just as descent starts we get back
         into the dirty layer
06:05   Clear sky,  still no lowcloud,  some Ci above or haze 12.34N 69.66E
06:10   Calling OPs center for update ....
06:20   Clouds again.  13N & 70.1E in a cloud field of st cu in a band
06:30   Many digital  pictures taken. haze is very dense, 13.3N & 70.5E back
         in low clouds
06:40   End of the cloud
06:50   Climb to get out of haze, one layer w/ top about 2500ft, yet there
         is a second layer visible to the eye above us
07:05   Same large layer up to the horizon.  SABL:  2 layers from 800m up to
         3.5km 15N & 71E
07:08   Above all haze, headed N; still a very heavy layer below us
07:10   Descent back into soup from 11,300ft
07:14   Level @ 9000ft for 15 minute sample
07:29   Slow descent down to 100ft to get good vertical profile
07:37   100ft leg for 5 minutes and then climb again
07:48   5 minute leg @ 3200ft in a very dirty layer
08:00   Underneath the haze at 7000 ft, up to 10000ft out of the haze
08:05   Sonde launch at altitude, headed for 8N & 70E
08:10   Over the haze; cirrus at the horizon.  Took many digital pictures
08:20   Can see small low clouds in the haze below us
08:25   Starting to see cirrus above aircraft; MCR images look beautiful.
         15% cloud cover under the haze.  Cirrus above.
08:33   Continuing heavy haze below w/ embedded clouds & cirrus above
08:44   Continuing cirrus above
08:55   Speed, pitch, & yaw maneuvers since the cirrus overhead is so thick
09:01   Maneuvers completed for now
09:20   Cirrus deck all over; cloud cover almost 100%; haze below low clouds
         below the haze
09:39   Cirrus overhead is thinning
09:41   Reverse heading maneuver
09:55   Back on course for Male
10:00   Still cirrus above & puffy Q below in haze, dry layer seen in sondes
         has disappeared so going to stop launches until Male
10:13   Still cirrus overhead
10:57   Sonde over KCO
11:08   Sonde over Male
11:09   Much cleaner over Male & also much less cirrus.
         No time left for MCR turn
11:10   Slow descent to S of Male
11:13   Area S of Male is full of small low clouds
11:29   Into clouds @ 4840ft on descent S of Male
11:33   Level @ 1000ft for Hudson, in haze, below clouds, 10 minute leg
11:48   Landing

Bruce Gandrud; NCAR/ATD, Boulder, CO, 80304, USA
email:  gandrud@ucar.edu
telephone: (303)497-1038   fax:(303)497-1092