Factor of safety (FoS), also known as (and used interchangeably with) safety factor (SF), is a term describing the structural capacity of a system beyond the expected loads or actual loads. Essentially, how much stronger the system is than it usually needs to be for an intended load.If I recall correctly, elevators are built with the highest FOS, 16, and believe it or not, planes are built with the lowest FOS: 1.5.
So rapid acceleration caused by rapid ascent or descent, resulting in significant forces, could exceed the planes structural strength.
St. Thomas, I am not an engineer, so I am not familiar with the term Factor of Safety. But as I pilot, I am familiar with load factor.
The jets I fly are stressed to about 3.8 G’s postive and 2.4 G’s negative. That is in reference to wing loading. We never come anywhere NEAR that in normal flight, in any realm of flight....take off, climb, cruise, descent and landing.
The cabin red line for pressurization is around 9 psi. Again, it is stressed for much more than that.
Flying near the ground/ocean is what planes do every day during take off and landing. I don’t see where the author is getting his ‘unusual stress’.