The scientific objective of this flight was focussed on making measurements directly off the coast of Christmas Island. The plan included a high altitude ferry for most of the distance from Fiji to Christmas Island, where a series of circles was planned to calculate fluxes from the ocean. An attempt was also made to sample downwind of the large populations of birds on the south side of the island on the approach to the airstrip, however this was not successful. The circles flown in the stack at Christmas Island were limited to 20 minso that a complete stack (of 4 circles) could be flown in the limited flight time. The four circles were of alternating directions at levels spaced throughout the boundary layer, and each circle was flown so as to advect with the wind. All circles were initiated at a heading of either 060 (clockwise) or 240 (counterclockwise) from the position 02o07'N, 156o30'W.

Take-off from Nadi was at 19:14. A fair amount of smoke and/or haze was present in over Fiji on take-off, perhaps due to brush or crop burning. At 19:55 we crossed over the second Fijian Island. At 20:03 we reached ferry altitude of 19,000'. At 20:05 we were above a deck of cirrus (or alto-stratus?), and at 20:12 we entered a cloud. At 20:20 we crossed over another small island. At 20:22 we were in the midst of lots of clouds (ITCZ?). At 20:41 we were out of cloud, although there were still scattered clouds below and large cumulus clouds directly ahead.

At 20:58 we passed over Wallis Island covered by scattered clouds. At 21:55 we were in a large cloud. At 22:00 Porter reported instrument problems with the 3010 and 3025. At 22:12 we were out of cloud. At 22:16 we were skimming over the tops of cumulus clouds. McMurry reported UFAs and Hudson reported very volatile CN. At 22:34 we were in cloud. At 22:40 we were out of cloud and there were high UFCN. At 22:44 we were back in cloud, and in clear air at 22:49. At 23:09 the onboard WINDS/Sun system failed and was rebooted.

At 23:23 Bradshaw reported ca. 10 min of high NO, which ended at 23:24 when we returned to clearer air. At 00:12 there were small cumulus clouds scattered below. At 01:25 we passed over Jarvis Island.

At 01:39 we prepared to start the descent for the first circle. Porter reported that the 3025 and 3010 were back on line, but that the 3010 concentrations were thought to be inaccurate. At 01:54 we started the profile down to the first circle at 1000'/min. At 02:03 we slowed our descent to 500'/min.

At 02:23:44 we reached the starting point (02o07'N, 156o30'W) for our first circle at 100'. This clockwise 20 min circle appeared to be primarily in clear air. At 02:43:44 we completed this circle and began to climb to 1500'. At 02:46:44 we started the second (counterclockwise) circle at 1500'. It was completed at 03:06:44 and we climbed to 3300'. At 03:14:31 we started the third (clockwise) circle (at the original starting point. No clouds were observed in the circle. At 03:34:31 we completed this circle and began to climb to 6000'. At 03:37:44 we started the final 6000' circle (counterclockwise). It was completed at 03:57:44 and we began a 10 min profile down heading west.

At 04:14 we crossed above where our exhaust should have been, but noted no CN signal.