Project to prove or disprove the possibility to kitefoil with an aerofoil instead of a hydrofoil. Ended

This project is to prove or disprove the possibility to kitefoil with an aerofoil instead of a hydrofoil.

Context:
Kite-foiling is a sport where the person can easily tack upwind by using a board with a hydrofoil and a kite. It's explained in detail here: https://www.straitstimes.com/multimedia/graphics/2024/05/max-maeder-olympics-kitefoiling-guide/index.html?shell

This works because the hydrofoil and the kite both generate lift (almost perpendicular to each other in different directions). The result is to overcome gravity and to create a forward pointing force to maintain speed and overcome drag.

Now this project is intended to prove or disprove whether it is in principle possible to replace the hydrofoil by an aerofoil.

Key differences of aerofoil vs hydrofoil scenario:
1) Density: The water has 800 times the density of air. So according to the lift equation also 800 times the potential lift.
2) Motion of the medium with the hydro/aerofoil: The water can be considered to have a velocity of 0 when hydrofoiling. However the air in the aerofoiling scenario is moving and likely in a downwind direction (more on that below).
3) Wind gradient: You can hydrofoil with the kite even when there's no vertical wind gradient, because the water is so dense and effectively has 0 velocity. In the aerofoil scenario it is my hypothesis that it is necessary to have a vertical wind gradient to succeed. If the kite and the aerofoil are both in the same windvector and we move our observation frame to move with the kite and the aerofoil, the effective wind on the kite and aerofoil will be 0 and they will just drift along with the wind. So a vertical wind gradient is necessary to make this work. For simplicity let's assume that the windvector for the aerofoil is exactly 0 and that the kite is experiencing a windvector of X (to be determined). In this way, once the aerofoil starts moving it can create a force against the non-moving air and the kite can create a force based on effective wind (windvector X + velocity in direction of movement).


Project questions:
1) Is it theoretically possible to follow a steady upwind tack with the kite / aerofoil combination?
2) Is it theoretically possible to follow a steady downwind tack with the kite / aerofoil combination?
3) Is it possible to move upwind by tacking in an upwind tack? That means to follow a tack upwind with a VMG (Velocity Made Good) which is faster than the windvelocity X (over the kite)?

Project deliverables:
1) A diagram showing the forces in the steady upwind tack scenario
2) A diagram showing the forces in the steady downwind tack scenario
3) A simulation to show that it is possible/impossible to move upwind read less