2. I have a look up table that plots energy capture for various latitudes vs day-of-year. It accounts for azimuth angle of the sun and duration of sunlight, where the integral of the area under the curve accounts for reduced collection at sunrise and sunset. To put it in perspective, operating on the worst winter day at 55 deg latitude is 15x harder than flying at the equator.
3. That produces triangular span loading (common to helicopters) which is not nearly as optimal as an elliptical span load distribution (common to gliders). Inboard sections just add weight and drag, without generating that much lift. The tether also has drag, but it's only 6% of the total system drag.
4. Agree. Takeoff has been completely revised and the transformational component has been abandoned. Now there is only a single motor on the outboard tip, and the system spins prior to takeoff. So the control laws for the retracted state are nearly identical to the extended state, just with a different set of gain values.
5. To build upon Q3, the tethers do have a very high Cd value (circular cross section is about 1.2), but they are extremely thin (small frontal area), and because the system rotates, the average velocity is 40% of the wingtip (which makes a huge deal for the V^2 in the drag equation).
6. At the largest scale, it takes nearly 40 seconds to make a full revolution. This slow rotation really helps to reduce the overall power requirements (P=VD).
