Narrative:

We departed runway 28 from bwi on the SWANN3 departure. The departure has you hold runway heading to 3 DME then turn left to 150. At 2.4 DME we were given direct to swann from potomac departure. We programmed the FMS with direct swann and the FMS commanded a right turn. Since we were not given a direction to turn; we turned to the shortest route. While in the turn; we were asked by a second controller to verify why we had turned right and we explained we had not reached the 3 DME fix and therefore turned the shortest route as displayed by the FMS.upon arrival we called potomac approach to verify the ambiguity and they said the tower should have issued us a turn. I believe there is some misunderstanding regarding the SID and tower instructions. Had we reached the 3 DME fix we would have initiated the turn to the left. In the future I suggest approach confirm the direction of turn for aircraft not turning and; I will be more skeptical of clearances that don't fit the SID narrative.

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Original NASA ASRS Text

Title: Corporate jet flight crew departing on the SWANN3 departure from BWI reported being issued a direct to SWANN from Potomac departure before the 3 DME fix where the SID calls for a left turn to 150. The crew reported programming the FMS for direct SWANN and the FMS commanded a right turn; which they followed.

Narrative: We departed RWY 28 from BWI on the SWANN3 departure. The departure has you hold runway heading to 3 DME then turn left to 150. At 2.4 DME we were given direct to SWANN from POTOMAC Departure. We programmed the FMS with direct SWANN and the FMS commanded a right turn. Since we were not given a direction to turn; we turned to the shortest route. While in the turn; we were asked by a second controller to verify why we had turned right and we explained we had not reached the 3 DME fix and therefore turned the shortest route as displayed by the FMS.Upon arrival we called POTOMAC approach to verify the ambiguity and they said the tower should have issued us a turn. I believe there is some misunderstanding regarding the SID and tower instructions. Had we reached the 3 DME fix we would have initiated the turn to the left. In the future I suggest approach confirm the direction of turn for aircraft not turning and; I will be more skeptical of clearances that don't fit the SID narrative.

Data retrieved from NASA's ASRS site 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.