To answer my own post, terminal velocity is the highest attainable speed (in one direction) of an object in free fall. Everything depends on the weight and shape of that object, and the direction it’s facing. Once an object reaches terminal velocity, it does not accelerate or slow down (a=0). It is constant unless the driving or resistive forces change. The driving force tries to cause motion; when falling, it’s gravity/weight. In the case of driving, it’s force from the engine (i.e. through friction on the tires). Sometimes, there’s multiple driving forces (i.e. an airplane in a dive, has the engine pushing it down at the same time gravity is pulling it down). Resistive force tries to resist motion, such as fluid friction (liquid or gas). Our object (payload) will not reach terminal velocity because its drag will not equal the gravitational pull.
Note from Kevin – You can note in this post that we’re targeting a 10 feet per second descent rate with our 4 foot inline parachute.