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At the end of the salt seeding experiments the question was when this deployment might be accomplished, since the research team had to disperse for a time to satisfy other commitments. Duncan Axisa, Gary Walker and Mike Hanneman (pilot of the Ag wagon) had commitments in India and Drs. Rosenfeld and Woodley had professional commitments in Europe and California, respectively. There wasa small window of opportunity for SPECTRA-II for roughly one week at the end of June 2005. This was rejected at too risky because it was understood that it is usually a mistake to schedule an aircraft measurement program for a single week under the expectation of suitable weather, because of the low probability that the desired weather will occur during that exact week. It was recommended, therefore, that SPECTRA-II not resume in June 2005.Indeed, this proved to be a good decision in that this week proved to be unsuitable. The Cheyenne cloud physics aircraft was committed for all of July for a measurement program in Houston, Texas. Much of August 2005 was open, however, for resumption of SPECTRA-II and it wasrecommended that the last three weeks of August 2005 be identified as the potential resumption period. Funding of this renewed activity wasgoing to be a problem, however, because all travel funds had been exhausted. 5.1What Was Planned but Did Not Happen Not all that was planned for SPECTRA II could be accomplished in the time that was allotted to the program. This included the following: Although project personnel and aircraft were deployed to Oklahoma in an attempt to obtain salt-seeding cases within range of the dual polarization radar as was planned, no cases were obtained because of unsuitable cloud conditions. The tight SPECTRA II budget did not permit redeployment. Time and weather did not permit deployment to Pleasanton, Texas for the planned glaciogenic seeding studies. This was left to later in the summer. Dr. David Prentice, M.D. was the main pilot of the Cheyenne cloud physics aircraft not Gary Walkeras planned originally, although Mr. Walker did pilot the aircraft on a few flights at the end of the program. The salt powder used in SPECTRA II was not sized in Texas prior to its use. Instead, it was assumed that the sizing of the salt powder particles performed in Israel (2-5 microns diameter) was valid. Because of the few seeding opportunities, randomization of the treatment decision was not practical. 5.2SPECTRA II Events That Were Not Planned Although much of SPECTRA II was an operational disappointment, the program had a few notable successes including: The qualification of three good salt-seeding cases in which the SFtracer gas was released at 6 cloud base and detected by the monitoring cloud physics aircraft. As will be documented later in this report, strong seeding signatures were documented in these cases. The development and use of a unique navigation and tracking system for use during the salt- seeding experiments. The problem that had to be faced at the outset of SPECTRA II was the real-time coordination of two aircraft in the selection, seeding and monitoring of convective clouds in a program designed to determine the effect of hygroscopic salt-powder seeding on the microstructure and precipitation-forming processes of convective clouds. The unique feature of the program was the release of SF6 tracer gas along with the powdered salt and later detection of the gas by the cloud physics aircraft,in order to know when it was making 21