diagrams, time-height curves, trajectories and photographs of significant flights, grouped by flight numbers. The flight numbering system has been revised since its inception and now only those flights in which an attempt was made to control the altitude of the balloon are included in the summary. Excluded are flights made to test special gear and launchings which were not successful.
Flights A, B, 1, 5, 6 and 7 all made use of meteorological balloons in various arrangements and combinations. Each flight included one or more "lifting balloons" which were to be released from the train when the desired altitude was reached, the other balloons then theoretically supporting the load at the constant altitude.
Figures 31 and 36 show the two methods used to group the balloons in clusters. Figure 31 shows the linear array borrowed from cosmic ray flight techniques; figure 36 shows the modified "Helios Cluster" in which lines from the balloons are joined at a central ring at the top of the load line.
The Helios cluster was by far the easier to handle because of the simpler rigging and the reduced launching strains.
Flight 7 was the only one of this group in which anything approaching a controlled altitude was attained. The previous flights failed to level off when the lifting balloons broke loose. In flights 1, 5 and 6, where ballast dropping devices were included, the ballast either did not drop, or the dropping did not have the desired effect. In flight 7, however, the cluster rose till the lifters were cut off, descended until sufficient ballast was dropped to cause the cluster to rise to a still higher altitude. There several balloons burst, resulting in a final descent. The time-height curve for this flight is shown as figure 38.