Narrative:

We were initially given the Ruudy5 SID. After reviewing the route I realized that this route was an RNAV SID and since our aircraft is unable to maintain RNP1 I called back and informed clearance about this fact. We then received TEB1 as our new clearance. About an hour later we loaded our passengers and got our clearance to taxi out to runway 24. After taxiing to 24 and we were cleared to take off and fly runway heading. All normal so far. After going through our normal takeoff procedures on a heading of 240 we were leveling off at 1500 ft MSL before making the turn to 280 as stated in the SID. Before making the turn the controller inquired as to whether or not we had already made the turn to 280. I replied that we were still on 240 as per the SID. After this is where I think things went awry. I heard the controller come back with turn left 270. This confused both me and my captain. I turned to him and asked him if heard the same thing that I did. He said that he did and I keyed back in to ask if the controller meant to say left. Again he came back with turn left 270. My captain keyed in and said something about seeing an aircraft to the left and not wanting to get that close. I believe he reiterated 270 and a left turn one more time but I can't be sure. Then a couple of moments later he came back with make an immediate right turn to 270 and climb to 6000 ft; which made more sense. My captain made the turn and began climbing and we continued on until about halfway through the flight and then we were asked to make a phone call after we landed. After landing my captain called the number and after the conversation with the controller's supervisor we were told that the controller was saying 'west' instead of 'left'. I'm not sure what any of us could have done different except the controller could have stuck to standard phraseology by saying turn left/right to 270 instead of saying 'west'.

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Original NASA ASRS Text

Title: Air taxi flight crew reported departing TEB and being given instructions by ATC to 'turn left' from 240 to a 270 heading which would put them in conflict with traffic during the turn. After querying ATC multiple times they were given a right turn. Later conversation with ATC revealed the Controller was using nonstandard phraseology by saying 'turn west' which the crew misinterpreted as 'turn left.'

Narrative: We were initially given the Ruudy5 SID. After reviewing the route I realized that this route was an RNAV SID and since our aircraft is unable to maintain RNP1 I called back and informed Clearance about this fact. We then received TEB1 as our new clearance. About an hour later we loaded our passengers and got our clearance to taxi out to Runway 24. After taxiing to 24 and we were cleared to take off and fly runway heading. All normal so far. After going through our normal takeoff procedures on a heading of 240 we were leveling off at 1500 ft MSL before making the turn to 280 as stated in the SID. Before making the turn the controller inquired as to whether or not we had already made the turn to 280. I replied that we were still on 240 as per the SID. After this is where I think things went awry. I heard the controller come back with turn Left 270. This confused both me and my captain. I turned to him and asked him if heard the same thing that I did. He said that he did and I keyed back in to ask if the controller meant to say left. Again he came back with turn Left 270. My captain keyed in and said something about seeing an aircraft to the left and not wanting to get that close. I believe he reiterated 270 and a left turn one more time but I can't be sure. Then a couple of moments later he came back with make an immediate right turn to 270 and climb to 6000 ft; which made more sense. My captain made the turn and began climbing and we continued on until about halfway through the flight and then we were asked to make a phone call after we landed. After landing my captain called the number and after the conversation with the controller's supervisor we were told that the controller was saying 'West' instead of 'Left'. I'm not sure what any of us could have done different except the controller could have stuck to standard phraseology by saying turn Left/Right to 270 instead of saying 'West'.

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.