0.01% and 99.9%, respectively (insert hand waving here).This is a combination of ridge lift and dynamic lift. How much is ridge and how much is dynamic soaring?
Dynamic soaring involves extracting energy out of the difference in airspeed through a shear layer - there's no requirement that the shear layer be level/horizontal. Ridge lift is merely a vertical component of the airspeed due to deflection by the ridge of the wind blowing over it - no shear layer is required. Airplanes running a ridge extract SOME energy from the rising air, but only enough to maintain altitude and airspeed - they do not accelerate to 10X their normal cruising airspeed (which, given the cubed ratio of power to velocity, implies using 1000X as much power to do so, give or take). So while a tiny bit of the energy used in these demonstrations comes from the vertical component of the airflow, almost all of it is coming from the dynamic soaring aspect.Should dynamic soaring flights be made over level ground if they are a demonstration of the capabilities of dynamic soaring?
While that's certainly where albatrosses (and maybe other sea birds) demonstrate it, it's hardly the only location where dynamic soaring can occur - anywhere there's a decent shear layer could be used, and in these RC cases, it's on the side of a hill, because that's where the shear is the strongest so the most amount of energy can be extracted.To clarify, a level surface with some surface roughness as in the open ocean where nature demonstrates dynamic soaring.
That's for dang sure.Still - Very interesting!