Narrative:

I was notified yesterday (10/90) of a deviation from a published SID. The departure winds were 110 degrees at 14 KTS. The letter, from the toronto supervisor for noise management, stated that the aircraft flew on course to 1000' and then drifted 9 degrees to the right of course. A ground track diagram shows a course correction at approximately 2/3 of the distance to the NDB which stopped the right drift and paralleled the correct course. The resultant fix was just over 1/2 mi south of the NDB. This is less than 1/2 mi off the southwest ot the northeast course line. This departure track is consistent with a decreasing right crosswind or a change to the wind from the left. Since the aircraft had no wind or drift display deviation to the right of course is countered by a turn back to the ADF needle plus a reduced correction to the right for drift. By the time it was determined that this second heading was not far enough to the left, station passage would have occurred. The time involved from noticing the first deviation until station passage would be less than 1 min. During that min aircraft flap confign was changed 3 times and engine power settings changed once. A 1/2 mi deviation would be insignificant except for the noise sensitive nature of the departure. I was not aware that I had passed that far from the fix. It is very difficult to fly direct to a close in NDB during a changing wind condition. I would suggest a dp that depicts flying a localizer course if greater precision is required.

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Original NASA ASRS Text

Title: HEADING TRACK DEVIATION ON SID NOISE ABATEMENT DEP.

Narrative: I WAS NOTIFIED YESTERDAY (10/90) OF A DEVIATION FROM A PUBLISHED SID. THE DEP WINDS WERE 110 DEGS AT 14 KTS. THE LETTER, FROM THE TORONTO SUPVR FOR NOISE MGMNT, STATED THAT THE ACFT FLEW ON COURSE TO 1000' AND THEN DRIFTED 9 DEGS TO THE RIGHT OF COURSE. A GND TRACK DIAGRAM SHOWS A COURSE CORRECTION AT APPROX 2/3 OF THE DISTANCE TO THE NDB WHICH STOPPED THE RIGHT DRIFT AND PARALLELED THE CORRECT COURSE. THE RESULTANT FIX WAS JUST OVER 1/2 MI S OF THE NDB. THIS IS LESS THAN 1/2 MI OFF THE SW OT THE NE COURSE LINE. THIS DEP TRACK IS CONSISTENT WITH A DECREASING RIGHT XWIND OR A CHANGE TO THE WIND FROM THE LEFT. SINCE THE ACFT HAD NO WIND OR DRIFT DISPLAY DEVIATION TO THE RIGHT OF COURSE IS COUNTERED BY A TURN BACK TO THE ADF NEEDLE PLUS A REDUCED CORRECTION TO THE RIGHT FOR DRIFT. BY THE TIME IT WAS DETERMINED THAT THIS SECOND HDG WAS NOT FAR ENOUGH TO THE LEFT, STATION PASSAGE WOULD HAVE OCCURRED. THE TIME INVOLVED FROM NOTICING THE FIRST DEVIATION UNTIL STATION PASSAGE WOULD BE LESS THAN 1 MIN. DURING THAT MIN ACFT FLAP CONFIGN WAS CHANGED 3 TIMES AND ENG PWR SETTINGS CHANGED ONCE. A 1/2 MI DEVIATION WOULD BE INSIGNIFICANT EXCEPT FOR THE NOISE SENSITIVE NATURE OF THE DEP. I WAS NOT AWARE THAT I HAD PASSED THAT FAR FROM THE FIX. IT IS VERY DIFFICULT TO FLY DIRECT TO A CLOSE IN NDB DURING A CHANGING WIND CONDITION. I WOULD SUGGEST A DP THAT DEPICTS FLYING A LOC COURSE IF GREATER PRECISION IS REQUIRED.

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.