A lot has to do with the design of a trimsheet system. A well thought out design, with due consideration given to Murphy's Law, can go a long way to reducing the incidence of error. One of the neatest procedures I have come across involves the determination of loading by conventional trimsheet (by a load controller type) with an independent crosscheck using a mechanical trimwheel by the operating crew on the flight deck. This check is very quick to use in practice and reduces the risk of untrapped errors getting through quite dramatically.
Reminds me of an audit in which I was involved some years ago. A quick look at the (FAR25 aircraft) trimsheet indicated that it had been printed incorrectly ... which followed from the original being printed incorrectly in the AFM ... can you believe it ? The sheet could be used .. but with some nuisance difficulty. I took the opportunity to ask (over a coffee) a number of operating pilots how they used the sheet. I can't remember how many chaps were in on the discussion but I got a great many innovative (but all wrong) ways to run the sheet ... that aspect of the audit rapidly turned into a training exercise ....
Last edited by john_tullamarine; 17th Sep 2002 at 09:44.