Yeah OK. But if our poor sod is writing to Qantas, Ansett, National Jet, Virgin etc, surely Dear Sir is acceptable? And if the airlines find Dear Sir as acceptable, then perhaps you should too. After all, if our PS has to make all these discreet phone calls to the switchboards of these operators, merely to obtain the gender of the Chief Honcho to whom to write, then he may be regarded as a nutter.