Originally Posted by
Hillbilly
FAR 117.19 states that the decision to extend is made jointly by the certificate holder (the company) and the PIC (the captain). From a technical standpoint, the FO never enters the equation unless he has been previously extended greater than 30 minutes and has not had the requisite 30 consecutive hours free from all duty.
Q-30. If the PIC concurs with the carrier for a 2-hour FDP extension, can the FO refuse the extension?
A-30. Yes. Each individual flightcrew member must “sign off”
that they are fit to fly before each segment, i.e., the PIC can
accept a 2-hour extension but the FO can independently
state he/she is not fit for further duty and could not under
the circumstances accept the extension.