GIVEN A DSCNT CLRNC WITH A RESTR; FATIGUED FLT CREW FAILS TO START DOWN UNTIL REMINDED BY ATC AND IS UNABLE TO MAKE THE RESTR.

Narrative

THE PURPOSE IS TO RPT FATIGUE WHILE FLYING. IT WAS MY 6TH STRAIGHT DAY OF FLYING ON RESERVE. WHILE LEVEL AT FL380; DCA-ORD; WE WERE GIVEN A CLRNC TO CROSS 30 MI E OF FWA AT FL340 WHICH WE ACKNOWLEDGED; BUT DID NOT START DOWN ON TIME. AT ABOUT 40 MI E; ATC QUERIED IF WE WOULD MAKE THE RESTR. I IMMEDIATELY BEGAN A DSCNT WHILE THE CAPT TOLD ATC WE WOULD BE CLOSE; BUT MISSED THE RESTR. ATC RESPONDED THAT IT WAS NO PROB AND TOLD US TO DISREGARD THE RESTR AND DSND TO FL340. WE LEVELED AT FL340 ABOUT 27 MI E OF FWA. THERE WERE NO TFC CONFLICTS TO MY KNOWLEDGE. THIS WAS JUST THE MOST BLATANT OF RED FLAGS IN MY RECENT FLYING. MISSED RADIO CALLS AND 'BREAKS' BY BOTH THE CAPT AND I HAVE BECOME MORE COMMON. THE GREATEST PROB IS THAT I DO NOT FEEL FATIGUED ENOUGH TO CLAIM 'TOO TIRED TO FLY' BEFORE A LEG. HOWEVER; ONCE AT ALT; I NOTICE SYMPTOMS/RED FLAGS OF FATIGUE. I BELIEVE THAT THE SCHEDULE DEMANDS CURRENTLY PLACED ON NARROW BODY RESERVES ARE A SAFETY OF FLT ISSUE AND WILL ULTIMATELY LEAD TO A FUTURE INCIDENT. PLEASE FILE NASA RPT WITH FULL TEXT ON MY BEHALF. THANK YOU.