Keith,
Excellent answer! I've known, intuitively, that this was the way it worked for a long time (this isn't the first time this question has been asked!), but I've never been able to explain it scientifically, nor have I seen anyone else able to do it until now!
It's also interesting to compare to an open cockpit, in which case, if the parrots were to take off, the mass (and weight) of the aircraft would decrease. Your explaination, if extended to the open cockpit case, also desribes why this is so.
(Re. the mass vs weight argument: weight = mass x acceleration. So, assuming that the acceleration (read g. loading) of the aircraft is the same, weight and mass can be considered equivalent for this problem. Arguments that one changes and the other doesn't, therefore, are invalid.)
FFF
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Last edited by FlyingForFun; 12th September 2002 at 16:34.