AN SMA PLT HANDED OVER HIS NAV CHORES TO A FATIGUED PLT.

Narrative

I WAS ASKED BY A FRIEND (PLT) IF I WOULD GO WITH HIM TO JOHNSTOWN; PA; IMMEDIATELY TO DROP OFF A FRIEND. MY FRIEND HAD HAD ONLY 3 HRS OF SLEEP IN THE PAST 48 HRS AND SAID HE WAS UNSAFE TO FLY WITHOUT A BACKUP PLT. I AGREED TO BE PIC AND SOON LEFT IN MY PA 28-180. LEAVING VPZ ON A LORAN COURSE SET FOR CAK; WE CLBED TO 7500 FT WITH MY BACKUP PLT AS NAVIGATOR. ABOUT 10 MI W OF CAK MY LORAN BLANKED OUT. I ASKED MY BACKUP PLT TO TAKE OVER THE CTLS DUE TO HAZE CONDITIONS OF 3-5; WHICH WOULD ALLOW ME TO REPROGRAM THE LORAN . I TUNED IN THE BSV VOR; SET THE 360 DEG RADIAL IN AND ASKED THE PLT TO FLY 120 DEGS AND INFORM ME WHEN WE WERE ON THE RADIAL. UPON PASSING IT I REQUESTED A COURSE OF 125 DEGS AND 10 E OF CAK I TOOK CTL AND DSNDED TO 3500 FT TO REMAIN CLR OF THE UPPER LIMITS OF PIT CLASS B AIRSPACE. I AGAIN GAVE THE CTLS TO THE PLT AND COMPLETED PROGRAMMING AND ACTIVATING THE LORAN. IT SHOWED A COURSE OF 110 DEGS NEEDED TO DEST. WE CONTINUED THAT COURSE UNTIL ARRIVING JST. UPON ARR I WAS ASKED TO RPT TO TWR AND WAS INFORMED OF MY INFRACTION OF ENTERING PIT AIRSPACE WITHOUT APPROVAL. UPON FURTHER ANALYSIS OF THEIR INPUT AND EVALUATION OF MY SECTIONAL; I RECOGNIZED THEY WERE CORRECT. MY ERROR WAS RELYING UPON A TIRED NAVIGATOR. IF HE WAS TOO TIRED TO PLT THEN HE SURELY WAS TOO TIRED TO NAV. I'M SURE HE SAW WE WERE OFF COURSE BUT IT JUST DID NOT REGISTER IN HIS MIND. IF I HAD HAD THE SECTIONAL IN MY LAP; I WOULD HAVE INTERPRETED IT CORRECTLY AND NAVIGATED AS NEEDED. WHEN WE WERE LOOKING TO THE L; WHERE WE THOUGHT THE ARPT WAS; IT WAS ACTUALLY TO THE R: WE WERE 25 MI OFF COURSE.