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|
Attributes | |
ACN | 1448940 |
Time | |
Date | 201705 |
Local Time Of Day | 1201-1800 |
Place | |
Locale Reference | DAL.Airport |
State Reference | TX |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Make Model Name | PC-12 |
Operating Under FAR Part | Part 135 |
Flight Phase | Climb |
Route In Use | SID HUBB9 |
Flight Plan | IFR |
Aircraft 2 | |
Make Model Name | B737 Undifferentiated or Other Model |
Operating Under FAR Part | Part 121 |
Flight Phase | Climb |
Flight Plan | IFR |
Person 1 | |
Function | Single Pilot |
Qualification | Flight Crew Air Transport Pilot (ATP) |
Events | |
Anomaly | ATC Issue All Types Deviation - Track / Heading All Types Inflight Event / Encounter Wake Vortex Encounter Inflight Event / Encounter Loss Of Aircraft Control |
Narrative:
Cleared for takeoff runway 13L at dal; with clearance to after departure turn left to 100 degrees; expect radar vectors to join the hubbard 9 SID and climb to 3000 ft. ATC issued caution for prior departing air carrier (aircraft Y) from that runway. Takeoff; initial left turn and initial climb were uneventful; but I kept my flaps at 15 for a steeper climb until retraction at about 2000 feet altitude. I was hand-flying with the yaw dampers (yd) on. Shortly after retracting my flaps; I sensed a strong; steady; smooth roll to the left. I instinctively countered with increasing right aileron input until I was at the limits of my physical arm strength. I initially suspected some sort of flight control/automation/yd/aileron trim malfunction; and deselected the yd. At this point; I was gradually yawing and rolling to the left. I could not stop that movement despite my strongest effort.suddenly; the left rolling force diminished; and my countering inputs turned me substantially to the right. I naturally decreased my inputs; and scanned my panel to see if there were any unusual annunciations (there were none). I looked out at my left wing to see if there were any unusual flight control indications (there were none). At this point I was just happy to be wings level and in control. ATC then issued an urgent left turn instruction; I am sure to mitigate reduced separation from the traffic departing from the parallel runway 13R. I complied immediately; and eventually resumed the SID.after the fact; I realized that I had encountered the wingtip vortex from aircraft Y in front of me. Having given (as a [check pilot]) and received (as a line pilot) hundreds of such events in decades of simulator flying; it was unlike any event I had experienced before. The simulator events were far more abrupt and violent; this real experience was smoother and built more gradually to an overpowering force level. I was sure I could avoid any vortices from the preceding aircraft Y by a steep climb and our initial left turn. That was obviously not the case. Perhaps insisting on increased separation in the takeoff interval would have been wise. Not sure that the pc-12 simulators can be programmed for such an event; but it would be helpful to experience it in that environment. What happened to me reminded me of previous simulator aileron trim runaway malfunctions; not wake turbulence encounters.
Original NASA ASRS Text
Title: PC-12 pilot reported encountering wake turbulence departing DAL in trail of B737 that produced an 'overpowering' roll.
Narrative: Cleared for takeoff Runway 13L at DAL; with clearance to after departure turn left to 100 degrees; expect radar vectors to join the Hubbard 9 SID and climb to 3000 ft. ATC issued caution for prior departing air carrier (Aircraft Y) from that runway. Takeoff; initial left turn and initial climb were uneventful; but I kept my flaps at 15 for a steeper climb until retraction at about 2000 feet altitude. I was hand-flying with the yaw dampers (YD) on. Shortly after retracting my flaps; I sensed a strong; steady; smooth roll to the left. I instinctively countered with increasing right aileron input until I was at the limits of my physical arm strength. I initially suspected some sort of flight control/automation/YD/aileron trim malfunction; and deselected the YD. At this point; I was gradually yawing and rolling to the left. I could not stop that movement despite my strongest effort.Suddenly; the left rolling force diminished; and my countering inputs turned me substantially to the right. I naturally decreased my inputs; and scanned my panel to see if there were any unusual annunciations (there were none). I looked out at my left wing to see if there were any unusual flight control indications (there were none). At this point I was just happy to be wings level and in control. ATC then issued an urgent left turn instruction; I am sure to mitigate reduced separation from the traffic departing from the parallel runway 13R. I complied immediately; and eventually resumed the SID.After the fact; I realized that I had encountered the wingtip vortex from Aircraft Y in front of me. Having given (as a [check pilot]) and received (as a line pilot) hundreds of such events in decades of simulator flying; it was unlike any event I had experienced before. The simulator events were far more abrupt and violent; this real experience was smoother and built more gradually to an overpowering force level. I was sure I could avoid any vortices from the preceding Aircraft Y by a steep climb and our initial left turn. That was obviously not the case. Perhaps insisting on increased separation in the takeoff interval would have been wise. Not sure that the PC-12 simulators can be programmed for such an event; but it would be helpful to experience it in that environment. What happened to me reminded me of previous simulator aileron trim runaway malfunctions; not wake turbulence encounters.
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.