Yet, such FMCs?, do not have the available obstacle data for the airport. so the info can only be taken with a grain of salt
... without the obstacle data, what use is the calculation ? .. unless you are taking off out over a flat desert or ocean ? I wouldn't even waste my salt on the numbers ...
Most biz jet operators are not as serious about their performance as commerical airline operators
.. then, are they as serious about the consequences of CFIT ?
what about the LPC or the glamorous lap top with performance calculation
.. the computer is not the problem .. any fool can put a set of AFM performance calculations into a software engine of one sort or another .. the problem is the boundary data for the day .. especially obstacle data ... GIGO never was truer than here ...