Originally Posted by
FrequentSLF
Understood, however I do wonder if what you say is correct, why such topic is being discussed so widely in this thread. I have seen so many different figures of estimated weight.
that's because everyone in this thread is (unless they are privy to the investigation and breaking the rules by posting here)
guessing. None of us know what Spanair's policy on weight calculations is. Or what the empty weight of that specific aircraft was (aircraft are weighed as part of maintenance every so often). Or what fuel load was on board. But it's safe to say that the crew had ONE figure for their takeoff weight, not a bunch of guesses. Was it precisely the weight of the aircraft - no. Was it close enough to be good enough - almost certainly.
You are confirming what I was thinking however I am still puzzled because the cost of load cell weighing system will be a few tens of thousand of Euro. The measured weight could be compared with the estimated weight adding an additional layer of safety. If the system is broken or in error the estimated weight could be used.
Why would I, as an airline, pay even that amount of money for a system which could only ever reduce my payload - since you're proposing using the estimated method as well. Such a system really only becomes attractive if I can add cargo or passengers when I use it. Yet by then it's too late, in all likelihood - once everyone is on board, I can't suddenly try to add more cargo without incurring delays.
snowfalcon has also noted a couple of the technical issues with such a system; they can be overcome, but its not simple.