Attached is a .pdf of with the most current design.
The design is a ‘strap-bud-blossom’ system: straps of 1-inch webbing, topped by a carabineer bud, blossoming out into 7 individual cells.
It is ‘double barrel’ because there are two stacks of 7-cluster cells. Look at the Assembled View, in the lower right corner, and the idealized top view of the double barrel.
In practice, the balloons don’t maintain their neat 7-cluster structure when you put then next to each other. They jumble around.
This is a 5 tier, 48-foot structure:
(1) Micro-vent tier, 7 balloons
(3) Standard/Core, non-release tiers, 14 balloons per tier, 42 balloons total
(1) Individual release tier
Specific elements not previously called out include the coloring of the top tier. The 55 envelopes are of mixed colors, but with a greater quantity of white balloons. The balloons in the individual release tier are all white, to minimize solar heating and expansion of the cells, to minimize the risk of solar expansion based bursting. The rest of the white balloons are in the topmost ‘core’ tier, for the same reason: solar heating.
The individual release balloons, in the topmost tier, are attached to the gondola via long 40-foot lines. The distinctive colored lines (red) can be released from the gondola, allowing the released line to snake up through the balloons, and float out with the released balloon out from the top of the system. There is possibility for the line snagging, but it is reduced compared to the other designs.
Releasing one of these balloons, from the 55 balloon system, is like venting about 1.8% of the total gas, which seems to be a large gas vent. What do you gas pilots think? Any idea how much gas you are releasing when you hit that line and open your top valve?
I’ve had a wonderful reception to this project, with many of suggestions and ideas. This is the design I’m looking to move forward with, so if you have improvement related critiques, this is the design to focus your attention on!
Jonathan R. Trappe