Following common airship practice, this blimp will fly slightly heavy (~200-1000 grams) balanced and trimmed like a conventional (in this case semi-acrobatic) aircraft. This allows the aircraft to slowly glide down in the upon propulsion loss, still controllable by the vee-tail. In the event of total control failure a heavy blimp comes down in due time, without sailing off to the next state.
Although the prop units are balance mounted in-line close to the envelope's (horizontal) center of drag (and mass), the tail's drag causes the design to pitch up a bit when power is applied and the tail surfaces are centered. Trimming the tail down levels flight and some lift is scavenged, as in conventional aircraft. To balance pitch up maneuvering advantage, the pitch down position of the vee tail lightly interacts with prop wash, due to placement of prop unit and vee-tail.
To promote easy flying, autonomous recovery, and emergency handling, the design has a bit of pendulum stability, balanced against a capability to loop and roll. In typical slightly heavy flight the vee-tail provides further roll stability due to its dihedral. Pendulum stability, general balance, propulsion and control surface placement are field tuned.
Loss of any one, two, or even three of the control surfaces or propulsion units results in partial rather than total loss of control. A single tail foil allows feeble steering in glide mode and a single motor allows a curly cue course by timed throttle application.
The flattened vee-tail imposes a coordinated roll/pitch turn technique much like the rudderless elevon design of the Flying Sphere prototype. Differential control of the propulsion units allows aggressive yaw turns. Modern RC gear allows for mixing and tuning standard pilot inputs to make unusual configurations intuitive to fly. A note on RC glider wing reuse for vee-tails- ...existing tab ailerons suffice for control at high speeds, but for close slow maneuvering rotating the entire wing is more effective. Ailerons can be frozen in place, used as trim tabs, or mechanically slaved to overall wing rotation to reduce stall.
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