Narrative:

We were sbound, on AR1, en route to ft. Lauderdale. We were navigating on the 197 degree bearing from carolina beach ADF. Reaching hobee intersection the arrival has you fly via 187 degree bearing to dimnd intersection. You ask yourself, the 187 degree bearing of what? Carolina beach? Hobee intersection is nearly 300 NM from carolina beach and the ADF pointer is always pointing 5 degrees one side or the other. I thought it odd to have to correct left to intercept the 187 degree bearing off carolina beach. It was at the end of a long day and I figured if we got off course ATC would advise as you hear them doing it constantly on those airways. It appears we did get off course. ATC at first said we were west of course. A moment later he corrected himself and gave us a heading of 240 degrees to correct. Part of the problem is that you are following a bearing from a station than a bearing from an intersection. Fine print at the top of the arrival chart says radar or RNAV required. We were in radar contact but I should have asked for a heading to dimnd. Trying to intercept a bearing 10 degrees to my left was too far. It's obviously incorrect, instead of saying 'radar or RNAV required' the chart may serve better by saying 'heading by ATC or RNAV required.' the bottom line here however is that I should have asked ATC for some direction when I first had doubts about the clearance.

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Original NASA ASRS Text

Title: FLC OF AN LGT FAILED TO FOLLOW ASSIGNED ARR TRACK DUE TO INADEQUATE ACFT NAV EQUIP. FAILED TO REQUEST RADAR VECTORS.

Narrative: WE WERE SBOUND, ON AR1, ENRTE TO FT. LAUDERDALE. WE WERE NAVING ON THE 197 DEG BEARING FROM CAROLINA BEACH ADF. REACHING HOBEE INTXN THE ARR HAS YOU FLY VIA 187 DEG BEARING TO DIMND INTXN. YOU ASK YOURSELF, THE 187 DEG BEARING OF WHAT? CAROLINA BEACH? HOBEE INTXN IS NEARLY 300 NM FROM CAROLINA BEACH AND THE ADF POINTER IS ALWAYS POINTING 5 DEGS ONE SIDE OR THE OTHER. I THOUGHT IT ODD TO HAVE TO CORRECT L TO INTERCEPT THE 187 DEG BEARING OFF CAROLINA BEACH. IT WAS AT THE END OF A LONG DAY AND I FIGURED IF WE GOT OFF COURSE ATC WOULD ADVISE AS YOU HEAR THEM DOING IT CONSTANTLY ON THOSE AIRWAYS. IT APPEARS WE DID GET OFF COURSE. ATC AT FIRST SAID WE WERE W OF COURSE. A MOMENT LATER HE CORRECTED HIMSELF AND GAVE US A HDG OF 240 DEGS TO CORRECT. PART OF THE PROB IS THAT YOU ARE FOLLOWING A BEARING FROM A STATION THAN A BEARING FROM AN INTXN. FINE PRINT AT THE TOP OF THE ARR CHART SAYS RADAR OR RNAV REQUIRED. WE WERE IN RADAR CONTACT BUT I SHOULD HAVE ASKED FOR A HDG TO DIMND. TRYING TO INTERCEPT A BEARING 10 DEGS TO MY L WAS TOO FAR. IT'S OBVIOUSLY INCORRECT, INSTEAD OF SAYING 'RADAR OR RNAV REQUIRED' THE CHART MAY SERVE BETTER BY SAYING 'HDG BY ATC OR RNAV REQUIRED.' THE BOTTOM LINE HERE HOWEVER IS THAT I SHOULD HAVE ASKED ATC FOR SOME DIRECTION WHEN I FIRST HAD DOUBTS ABOUT THE CLRNC.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.