Narrative:

While en route from ZZZ to cyhz; we're given our clearance as filed. We were given several shortcuts to various fixes as we naved over new york city. About 20-30 mi or so north of new york city; we were 'cleared direct destination.' this 'cleared direct' pretty much cleared out a page and a half of fixes on our route in the FMS. Both the captain and I were monitoring on the mfd with the terrain feature turned on to view our distance from shore as we were now heading over the water. However; at the moment we were cleared; we had to zoom way out the viewing scale to see our entire flight path. At that resolution; we were confident that we would be within 50 mi of shore. We then zoomed our mfd's back to 50 NM arc to monitor. As our flight progressed; I took my mfd off of the map page to view the status of all the system; spending a couple of mins on each page monitoring them and watching for abnormalities. When I cycled back to the map page; both the captain and I realized there was only a small speck of land in the 50 mi arc and it was disappearing fast. The captain told me to make an immediate left turn towards shore at the same time he advised ATC of the situation. They cleared us to deviate left as necessary and that we could return direct cyhz when able. Because the shoreline recessed westerly; it took a few mins to get within 50 mi of shoreline. And this; of course; is estimated on the accuracy of the terrain feature on the map page. If I had to guess; I would say we were no more than 55 mi from shore while deviating west of course. After about 5 mins; we had plenty of shoreline to our left and the right; and we proceeded back to direct cyhz and landed uneventfully.

Google
 

Original NASA ASRS Text

Title: E170 FLT CREW ACCEPTS ROUTING DIRECT TO CYHZ. THEY LATER DISCOVER THE ROUTE TAKES THEM BEYOND 50 MILES OFF SHORE.

Narrative: WHILE ENRTE FROM ZZZ TO CYHZ; WE'RE GIVEN OUR CLRNC AS FILED. WE WERE GIVEN SEVERAL SHORTCUTS TO VARIOUS FIXES AS WE NAVED OVER NEW YORK CITY. ABOUT 20-30 MI OR SO N OF NEW YORK CITY; WE WERE 'CLRED DIRECT DEST.' THIS 'CLRED DIRECT' PRETTY MUCH CLRED OUT A PAGE AND A HALF OF FIXES ON OUR RTE IN THE FMS. BOTH THE CAPT AND I WERE MONITORING ON THE MFD WITH THE TERRAIN FEATURE TURNED ON TO VIEW OUR DISTANCE FROM SHORE AS WE WERE NOW HEADING OVER THE WATER. HOWEVER; AT THE MOMENT WE WERE CLRED; WE HAD TO ZOOM WAY OUT THE VIEWING SCALE TO SEE OUR ENTIRE FLT PATH. AT THAT RESOLUTION; WE WERE CONFIDENT THAT WE WOULD BE WITHIN 50 MI OF SHORE. WE THEN ZOOMED OUR MFD'S BACK TO 50 NM ARC TO MONITOR. AS OUR FLT PROGRESSED; I TOOK MY MFD OFF OF THE MAP PAGE TO VIEW THE STATUS OF ALL THE SYS; SPENDING A COUPLE OF MINS ON EACH PAGE MONITORING THEM AND WATCHING FOR ABNORMALITIES. WHEN I CYCLED BACK TO THE MAP PAGE; BOTH THE CAPT AND I REALIZED THERE WAS ONLY A SMALL SPECK OF LAND IN THE 50 MI ARC AND IT WAS DISAPPEARING FAST. THE CAPT TOLD ME TO MAKE AN IMMEDIATE L TURN TOWARDS SHORE AT THE SAME TIME HE ADVISED ATC OF THE SIT. THEY CLRED US TO DEVIATE L AS NECESSARY AND THAT WE COULD RETURN DIRECT CYHZ WHEN ABLE. BECAUSE THE SHORELINE RECESSED WESTERLY; IT TOOK A FEW MINS TO GET WITHIN 50 MI OF SHORELINE. AND THIS; OF COURSE; IS ESTIMATED ON THE ACCURACY OF THE TERRAIN FEATURE ON THE MAP PAGE. IF I HAD TO GUESS; I WOULD SAY WE WERE NO MORE THAN 55 MI FROM SHORE WHILE DEVIATING W OF COURSE. AFTER ABOUT 5 MINS; WE HAD PLENTY OF SHORELINE TO OUR L AND THE R; AND WE PROCEEDED BACK TO DIRECT CYHZ AND LANDED UNEVENTFULLY.

Data retrieved from NASA's ASRS site as of May 2009 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.