disclaimer for fellow chaps showing up for free ride
 

in some countries they are generally accepted as "extra crew" but as it is obvious problems would arise for next of skin of captain after a crash I would like to let them sign a disclaimer and make a remark on the loadsheet to be sure it will not be lost in case...
who can help with a waterproof wording?

Normally noted as extra crew member or additional crew member...if you give details, may be able to help...maybe.