If the link works, it will take you back about a year, to a video John and I put together for 'The Aerodynamics of Towing.'
At 13:24, we've presented the Cybertruck with it's range-extender battery inside the fully-gap-filled, tadpole trailer, which allows the truck's Cd to fall into Cd 0.15 territory.
The drag reduction helps compensate for the added mass and rolling-resistance of the trailer, which is overshadowed by the delta-CdA.
The November30, 2023 range extender pack would be removed from the Cybertruck's vault, and relocated to the tadpole, leaving the bed with its maximum load volume intact.
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