Oh wow, there's another possibility: one of my pet theories is that
the top trim of the Tesla Pickup Truck might be amphibious, with seamless offroad and "speedboat" capabilities.
For that it would require either a marine propeller and rudder at the back ... or it could intelligently repurpose its four wheels to generate forward thrust.
The problem with that idea is that the wheels on the road are aerodynamic, which gives them very little forward thrust in water by default.
But what if the wheel covers are actuated with hydraulics, like a controllable pitch propeller (CPP), which would not only generate fairly substantial thrust, but would also allow steering in a two motor setup which has normally limited left/right rotational differential?
This solves four difficult engineering and reliability problems rather elegantly:
- No rudder required (rudders are fragile anyway),
- thrust can be stabilized even if the angle of attack isn't perpendicular, such as when crossing a fast flowing river,
- thrust can be maximized for efficiency versus control authority,
- no need to hide the wheels from the flow of water, if they are the means of thrust generation.
The "submarine car" joke from Elon might have been another secret teaser in plain sight.
My crazy prediction for the Pickup Truck unveil: it will be next to a significant body of water.
