A SAAB 340 CREW FAILED TO CHECK BLOCK TIME FOR A FIVE LEG DAY THAT MAY EXCEED EIGHT BLOCK HOURS BECAUSE OF THE ACFT'S RUDDER LIMITED CONDITION.

Narrative

WE ACCEPTED ACFT IN ZZZ AT XA12 LCL FOR A 5 LEG DAY TRIP. THE ORIGINAL BLOCK TIME WAS 7:51 FOR THIS PARTICULAR DAY TRIP. ACFT WAS RUDDER LIMITED AND HAD ARRIVED THE PREVIOUS EVENING IN ZZZ WITH THIS DEFERRED ITEM. UPON ACCEPTING THE ACFT; THE FO AND I DID THE RUDDER TEST AND VERIFIED THE PROPER MEL ITEMS WERE FOLLOWED; BUT IT NEVER OCCURRED TO ME TO CALL SCHEDULING TO DETERMINE IF OUR BLOCK TIMES HAD BEEN CHANGED TO REFLECT THIS RUDDER LIMITED ACFT. AS IT TURNED OUT; WE HAD KEPT THIS ACFT ALL DAY FOR THE 5 LEGS AND DURING THE LAST LEG THE FO BROUGHT UP A PASSAGE IN THE POM ABOUT RUDDER LIMITED ACFT AND THE FACT SCHEDULING NEEDS TO CHANGE BLOCK TIME FOR RUDDER LIMITED ACFT AND WE HAD A REVELATION THAT PERHAPS I SHOULD HAVE CALLED ABOUT THIS EARLIER IN THE DAY. I SUPPOSE INFORMING CREWS OF THE PASSAGE IN THE POM IN RECURRENT OR INITIAL GND SCHOOLS MIGHT HELP AND ADDING A PASSAGE IN THE MEL-CDL BOOK THAT DIRECTS CREW TO THE PASSAGE IN THE POM (OPS MANUAL) REFLECTING THE CHANGE IN BLOCK TIME THAT NEEDS TO BE DONE BY CREW SCHEDULING.