Chris opined

How do aircraft manufactures determine the maximum gross weight for a
given plane? I know I've come across articles that mention on a cool day
you can go over the max. gross weight by a percentage, I think 20% was
thrown out there but not sure. Then again, on a hot day you might not
get any where near that. Is it determined by a standard temp?

The maximum weight is determined by the one of the following, roughly
speaking;

structural strength, nothing breaks before 6gs

climb rate at sea level in take off configuration

climb rate at sea level in landing configuration

stall speed, landing configuration

others that I am not aware of.


At some point adding more weight will cause an aircraft to fail one or more
of the FAAs minimum performance standards.

Changing parts of an aircraft can change the gross weight. Extra fuel can be
put in tip tanks, reducing flap travel can increase gross weight.


-ash
Cthulhu for President!
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