Skywise wrote:

Knowing the weight of your passengers
and cargo is part of your duty as pilot in command, is it not?

Not necessarily. Knowing that the aircraft is at or below MGW and within the
envelope is part of your duty as PIC. If you have enough passengers and luggage
to be close to MGW, then, yes, you need to know the weights. If not, you don't.

For example, my Maule would carry 560 pounds with full tanks. Going up with a
single passenger, I never had to ask that person what they weighed. I simply
don't know people who weigh well over 350 pounds. I know that putting more than
210 pounds in the back seat will put me out of the envelope. If the EAA brings
me two typical 10 year olds, I know I can put them in the back seat with no
problems for a Young Eagles flight, and I can tell that by looking at them.

The only time I needed to know exact weights were when I took my family on
vacations.

George Patterson
Why do men's hearts beat faster, knees get weak, throats become dry,
and they think irrationally when a woman wears leather clothing?
Because she smells like a new truck.