Originally Posted by
PENKO
Ouch!
Sorry, PENKO, I didn't mean to hurt ...
Originally Posted by
PENKO
Let's keep it simple, I'm no scientist. If a newly pressurized scuba tank weighs more than one that has been used for a one hour dive then for sure any airplane being pressurized will weigh more than an unpressurized one in otherwise equal circumstances.
I do think this answers the original question very well in non-technical terms.
In summary, when the cabin is pressurised, of course there is more air in the cabin and so there will be more mass (i.e. it will weigh more). However, the increase in mass in proportion to the total mass of the aircraft is proportionately so small as to be negligible.
JD
