MIT Mystery Hunt 2020/Drawing Board

Drawing Board is a physics puzzle from the round of the 2020 MIT Mystery Hunt. It is presented as a series of sketches detailing the layout of a proposed roller coaster.

Puzzle Elements
Flavortext - ''Geez, kid. You're the most enthusiastic intern we've ever had, but this roller coaster design needs a lot of work. Back to the drawing board... J''

Hint in Flavortext - A very subtle hint, but the "Geez" at the beginning is meant to clue at the usage of g as the unit of acceleration of choice for this puzzle.

Physics - The majority of this puzzle involves calculations using centripetal acceleration and conversions between potential and kinetic energy. At each place where the roller coaster experiences acceleration (at the bottom of a loop, at the top of a loop, and during sections of free fall), calculate the acceleration in terms of g.

Alphanumeric Extraction - The accelerations turn out to be (within rounding error) integer multiples of g, where the integer is at most 26. Converting these to letters yields the answer to this puzzle.