Narrative:

We were on the mrlin 4 arrival to fll. We were heading easterly, instead of southeasterly as is normal on the omn-tripl segment. This was due to a line of thunderstorms off our right (south) of us. We were paralleling the line. There was a small opportunity to turn south in between 2 cells, which was missed. I requested a 60 degree right turn, but ATC kept saying 'you are cleared to deviation east,' direct tripl when able. We thought they might let us take a shortcut to dubbl -- we both thought they had said direct dubbl when able. But with this confusion we continued east. If we had turned south to go between the 2 cells, we would have had to turn north to get back up to tripl. When we were approaching the last cell off our right and were getting ready to go around it and head southwest, ATC asked if we were overwater equipped. We said no, and he said that he showed us more than 50 mi offshore, and that he didn't think that we could do that. I said that we couldn't fly into thunderstorms. At that time we were turning right to go around the last cell and head back to land. I believe we took the safest course of action -- avoiding the thunderstorms. I knew that we could exceed the 50 mi limit for WX, but I didn't remember until later the part about declaring an emergency. As it is, the arrival has you 35 mi out to sea, and with any WX on the arrival, there is not much distance to work with. As I don't want to have to declare an emergency in the first place, in the future I will query ATC about our distance from shore, to wake them up to the potential problem, and say something like 'if we continue on this heading for 20 more mi, will that keep us within 50 NM off shore? If not, can we turn west and try another arrival route?

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Original NASA ASRS Text

Title: A B737, NOT EQUIPPED FOR OVERWATER FLT, DEVIATES MORE THAN 50 NM OFFSHORE WHILE AVOIDING TSTM ACTIVITY ON THE MRLIN 4 ARR INTO FLL, FL.

Narrative: WE WERE ON THE MRLIN 4 ARR TO FLL. WE WERE HEADING EASTERLY, INSTEAD OF SOUTHEASTERLY AS IS NORMAL ON THE OMN-TRIPL SEGMENT. THIS WAS DUE TO A LINE OF TSTMS OFF OUR R (S) OF US. WE WERE PARALLELING THE LINE. THERE WAS A SMALL OPPORTUNITY TO TURN S IN BTWN 2 CELLS, WHICH WAS MISSED. I REQUESTED A 60 DEG R TURN, BUT ATC KEPT SAYING 'YOU ARE CLRED TO DEV E,' DIRECT TRIPL WHEN ABLE. WE THOUGHT THEY MIGHT LET US TAKE A SHORTCUT TO DUBBL -- WE BOTH THOUGHT THEY HAD SAID DIRECT DUBBL WHEN ABLE. BUT WITH THIS CONFUSION WE CONTINUED E. IF WE HAD TURNED S TO GO BTWN THE 2 CELLS, WE WOULD HAVE HAD TO TURN N TO GET BACK UP TO TRIPL. WHEN WE WERE APCHING THE LAST CELL OFF OUR R AND WERE GETTING READY TO GO AROUND IT AND HEAD SW, ATC ASKED IF WE WERE OVERWATER EQUIPPED. WE SAID NO, AND HE SAID THAT HE SHOWED US MORE THAN 50 MI OFFSHORE, AND THAT HE DIDN'T THINK THAT WE COULD DO THAT. I SAID THAT WE COULDN'T FLY INTO TSTMS. AT THAT TIME WE WERE TURNING R TO GO AROUND THE LAST CELL AND HEAD BACK TO LAND. I BELIEVE WE TOOK THE SAFEST COURSE OF ACTION -- AVOIDING THE TSTMS. I KNEW THAT WE COULD EXCEED THE 50 MI LIMIT FOR WX, BUT I DIDN'T REMEMBER UNTIL LATER THE PART ABOUT DECLARING AN EMER. AS IT IS, THE ARR HAS YOU 35 MI OUT TO SEA, AND WITH ANY WX ON THE ARR, THERE IS NOT MUCH DISTANCE TO WORK WITH. AS I DON'T WANT TO HAVE TO DECLARE AN EMER IN THE FIRST PLACE, IN THE FUTURE I WILL QUERY ATC ABOUT OUR DISTANCE FROM SHORE, TO WAKE THEM UP TO THE POTENTIAL PROB, AND SAY SOMETHING LIKE 'IF WE CONTINUE ON THIS HDG FOR 20 MORE MI, WILL THAT KEEP US WITHIN 50 NM OFF SHORE? IF NOT, CAN WE TURN W AND TRY ANOTHER ARR RTE?

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.