The question seemed to be geared toward how I would respond to the question, as opposed to getting the correct answer. I asked them if the seats of the plane were in or out? Was the plane outfitted with reinforced steel to support the addional weight of the ball bearings? Was the plane expected to fly with the ball bearings on board? After I asked these questions and acted like I was actually trying to answer the question, they stopped me and moved on to the next question, thereby confirming my theory that the question was geared toward my response and not the actual answer.
After finding the job listing on Glassdoor, and doing a little research on the company and its product(s), I found that it was a great nexus between my skillset and their needs, and I felt it was time to get back to teaching as my primary function, which was the primary function of their job posting.