Here's a reference I found to "edge case" and "corner case" with respect to a flight envelope:
https://www.researchgate.net/figure/An-example-flight-envelo...(I found this by searching for the terms "edge case" and "flight envelope" together.)
Also, the Wikipedia "corner case" article talks about how this terminology relates to the flight envelope metaphor:
> The term "corner case" comes about by physical analogy with "edge case" as an extension of the "flight envelope" metaphor to a set of testing conditions whose boundaries are determined by the 2^n combinations of extreme (minimum and maximum) values for the number n of variables being tested, i.e., the total parameter space for those variables. Where an edge case involves pushing one variable to a minimum or maximum, putting users at the "edge" of the configuration space, a corner case involves doing so with multiple variables, which would put users at a "corner" of a multidimensional configuration space.
https://en.wikipedia.org/wiki/Corner_case
