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'''May 18 1007 PDT:''' By this time, the ascent rate had averaged no more than 0.1 m/s, and concerns were raised that the trajectory would not clear the Diablo Range to the southeast of Hollister, which had peak elevations in excess of 1000m. It was reasoned that since the trajectory followed the San Benito River valley, there would be ample time to clear the range. However, to be safe, and in response to a further loss of altitude at 260m, a further ballast command was sent.
'''May 18 1007 PDT:''' By this time, the ascent rate had averaged no more than 0.1 m/s, and concerns were raised that the trajectory would not clear the Diablo Range to the southeast of Hollister, which had peak elevations in excess of 1000m. It was reasoned that since the trajectory followed the San Benito River valley, there would be ample time to clear the range. However, to be safe, and in response to a further loss of altitude at 260m, a further ballast command was sent.
'''May 18 1013 PDT:''' Trajectory turns northeastward over south Hollister at an altitude of approximately 500m. This was alarming as it meant the balloon would approach the mountains more quickly. However, as the ascent rate had risen above 0.5 m/s, no further action was taken.
'''May 18 1013 PDT:''' Trajectory turned northeastward over south Hollister at an altitude of approximately 500m. This was alarming as it meant the balloon would approach the mountains more quickly. However, as the ascent rate had risen above 0.5 m/s, no further action was taken.
'''May 18 1100 PDT:''' After nearly an hour of steady ascent at 0.6 m/s, balloon clears the Diablo Range at an altitude of 2.5 km. As it had done so by means of Pacheco Pass, the maximum ground elevation did not exceed 700m. Concerns were therefore raised that the most recent ballast event was unnecessary, as 0.6 m/s risked popping before sunset. It was hoped that the recent steady ascent was due to the air mass ascending the slope of the Diablo Range.
'''May 18 1100 PDT:''' After nearly an hour of steady ascent at 0.6 m/s, balloon cleared the Diablo Range at an altitude of 2.5 km. As it had done so by means of Pacheco Pass, the maximum ground elevation did not exceed 700m. Concerns were therefore raised that the most recent ballast event was unnecessary, as 0.6 m/s risked popping before sunset. It was hoped that the recent steady ascent was due to the air mass ascending the slope of the Diablo Range.
'''May 18 1128 PDT:''' Despite passing over the descending slopes of the Diablo Range, steady ascent continued and even accelerated at one point to over 1.5 m/s.
'''May 18 1128 PDT:''' Despite passing over the descending slopes of the Diablo Range, steady ascent continued and even accelerated at one point to over 1.5 m/s.
'''May 18 1143 PDT:''' After slowing ascent, balloon reaches maximum altitude at 4430m over (37.3780, -121.0420). Balloon then begins to descend. At the time, this was viewed as a blessing, as it bought time for the rest of the ascent.
'''May 18 1143 PDT:''' After slowing ascent, balloon reached maximum altitude at 4430m over (37.3780, -121.0420). Balloon then began to descend. While it was not clear at the time why ascent stopped, it is apparent in retrospect that the trajectory had entered areas of inclement weather, and downdrafts and/or rain were pushing the balloon downward.
'''May 18 1153 PDT:''' Descent rate accelerates to an alarming 2.0 m/s over (37.462, -120.970).
'''May 18 1153 PDT:''' Descent rate accelerated to an alarming 2.0 m/s over (37.462, -120.970). Although it was believed that the equilibrium ascent rate was already too high, ballasting was seriously considered in light of this rapid descent.
'''May 18 1220 PDT:''' After two ballast events, the trajectory leveled off over (37.713, -120.908), reaching a minimum altitude of 1220 m, and then resumed ascent just above 0.5 m/s. This was viewed as having effectively delayed launch by 2 hours and therefore a net benefit for mission endurance.
'''May 18 1331 PDT:''' Balloon equilibrates at 3431m, a second altitude maximum, over (38.082, -120.868).
'''May 18 1341 PDT:''' Balloon descends at over 2 m/s less than 2km above the ground, again likely due to downdrafts and/or rain, prompting a series of frantic ballast events. Due to the low altitude and rising ground elevation, the trajectory was within two communications intervals of flight termination. All hopes of a long-endurance flight had been abandoned; survival was the only priority.
'''May 18 1416 PDT:''' Descent slows and balloon reaches a minimum altitude of 351m, less than 80m above the ground elevation of 285m at (38.277, -120.799) (due to hilly terrain, it is possible the balloon was even closer to the ground and maybe even made contact). Nevertheless, the trajectory was recovered and ascent resumed.
'''May 18 1446 PDT:''' After several consecutive intervals of ascent, sudden descent was observed at a rapid enough speed to terminate flight by the next communication. A ballast interval was sent --- too little, too late in retrospect.
'''May 18 1451 PDT:''' Balloon reported its final resting coordinates and elevation. After the next communication, flight termination was confirmed.
'''May 19 1608 PDT:''' Communications ceased, presumably due to rain. By now it had become clear that at least the last two hours of the flight had been in the midst of inclement weather.
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