Narrative:

We pushed back from the gate at bwi with a quick turnaround. Behind schedule, we were already behind the power curve. The INS was not put in align and therefore became immediately unusable. Looking at the charts, it was apparent that short range navigation could be used on this short north/south trip to the caribbean. Headed out from ilm with the ADF as primary reference. 8 to 10 mins later, ATC called and said we were 10 mi to the east of course. Corrected to the right and saw traffic overhead, headed same direction so we then played follow the leader southward. About 250 mi south, I was able to get another x-nav check and to my dismay, just when I found we were 10 mi off track (apparently following an aircraft on a parallel but diverging route,. ATC called and asked what route had we been cleared on, and did you know you were 20 mi off course?

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Original NASA ASRS Text

Title: WDB FLC NEGLECTS TO ALIGN INS PRIOR TO DEP. NAV ERROR.

Narrative: WE PUSHED BACK FROM THE GATE AT BWI WITH A QUICK TURNAROUND. BEHIND SCHEDULE, WE WERE ALREADY BEHIND THE PWR CURVE. THE INS WAS NOT PUT IN ALIGN AND THEREFORE BECAME IMMEDIATELY UNUSABLE. LOOKING AT THE CHARTS, IT WAS APPARENT THAT SHORT RANGE NAV COULD BE USED ON THIS SHORT N/S TRIP TO THE CARIBBEAN. HEADED OUT FROM ILM WITH THE ADF AS PRIMARY REF. 8 TO 10 MINS LATER, ATC CALLED AND SAID WE WERE 10 MI TO THE E OF COURSE. CORRECTED TO THE R AND SAW TFC OVERHEAD, HEADED SAME DIRECTION SO WE THEN PLAYED FOLLOW THE LEADER SOUTHWARD. ABOUT 250 MI S, I WAS ABLE TO GET ANOTHER X-NAV CHK AND TO MY DISMAY, JUST WHEN I FOUND WE WERE 10 MI OFF TRACK (APPARENTLY FOLLOWING AN ACFT ON A PARALLEL BUT DIVERGING RTE,. ATC CALLED AND ASKED WHAT RTE HAD WE BEEN CLRED ON, AND DID YOU KNOW YOU WERE 20 MI OFF COURSE?

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.