(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.
(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