Narrative:

I was the PF/receiving training on this flight. After takeoff I experienced a sudden small roll to the left. I was hand flying and visually corrected back to wings level. We would penetrate clouds soon so I selected both pitot heat switches to the on position. The right pitot heat circuit breaker immediately blew. An attempted reset was unsuccessful. We were assigned a right turn to a 095 (I believe) heading. After turning to the assigned heading; I experienced another small but sudden left roll. I then switched on the auto pilot in heading mode as we continued to climb. I then noticed the airspeed seemed to be fluctuating. Not wanting to enter the clouds with system malfunctions; I started a turn to a right downwind leg while discontinuing the climb. I was reminded by the PNF/instructor that the auto pilot was on and I was inadvertently fighting it. As this was being discussed; I felt another small roll. I shut off the auto pilot and informed the PNF/instructor that I was having control problems and did not wish to continue. After the auto pilot was turned off; we still experienced intermittent rolls. The PNF then informed the tower that we wanted to return to [departure airport]. They started vectors for sequencing to follow other aircraft so I informed the PNF that the control issues were still continuing. He then told ATC that we requested immediate landing clearance. Airspeed was fluctuating wildly and I then found out that the copilot airspeed was also fluctuating. While selecting the landing gear to the down position; I noticed that all three gear lights were already on. The gear had apparently never retracted and I had not yet noticed due to the other distractions. We landed without further incident. We noticed the emergency trucks proceeding along the airport perimeter. After receiving taxi clearance and heading along the parallel; we informed ground that we seemed to be fine now and they could call off the trucks. Approximately 1000 feet from the FBO; we noticed white smoke billowing from the defrost ducts. We then informed ground to send the crash fire rescue equipment vehicles to the ramp; and that we had smoke in the cockpit. We parked away from the buildings by the grass; powered down and evacuated. After assuring the passengers were safe and well clear; I opened the left nose baggage door and white smoke billowed out. The fire crew inspected the aircraft and found no fire but did notice scorch marks and minor smoke on the bulkhead baggage compartment vertical wall. At the time of this writing; no further evaluation has been done to determine the exact cause of the seemingly unrelated events.

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Original NASA ASRS Text

Title: C414 pilot and flight instructor experienced several uncommanded wing rolling movements; possibly from wake turbulence; as well as electrical problems that resulted in a return to the field. After landing; smoke was observed in the cabin. Residual fuel from the cabin heater was reported to have been ignited by a shorted wire bundle which was likely also the source of the electrical problems.

Narrative: I was the PF/Receiving training on this flight. After takeoff I experienced a sudden small roll to the left. I was hand flying and visually corrected back to wings level. We would penetrate clouds soon so I selected both pitot heat switches to the ON position. The right pitot heat circuit breaker immediately blew. An attempted reset was unsuccessful. We were assigned a right turn to a 095 (I believe) heading. After turning to the assigned heading; I experienced another small but sudden left roll. I then switched on the auto pilot in HDG mode as we continued to climb. I then noticed the airspeed seemed to be fluctuating. Not wanting to enter the clouds with system malfunctions; I started a turn to a right downwind leg while discontinuing the climb. I was reminded by the PNF/Instructor that the auto pilot was ON and I was inadvertently fighting it. As this was being discussed; I felt another small roll. I shut off the auto pilot and informed the PNF/Instructor that I was having control problems and did not wish to continue. After the auto pilot was turned OFF; we still experienced intermittent rolls. The PNF then informed the tower that we wanted to return to [departure airport]. They started vectors for sequencing to follow other aircraft so I informed the PNF that the control issues were still continuing. He then told ATC that we requested immediate landing clearance. Airspeed was fluctuating wildly and I then found out that the copilot airspeed was also fluctuating. While selecting the landing gear to the DOWN position; I noticed that all three gear lights were already on. The gear had apparently never retracted and I had not yet noticed due to the other distractions. We landed without further incident. We noticed the emergency trucks proceeding along the airport perimeter. After receiving taxi clearance and heading along the parallel; we informed Ground that we seemed to be fine now and they could call off the trucks. Approximately 1000 feet from the FBO; we noticed white smoke billowing from the defrost ducts. We then informed Ground to send the CFR vehicles to the ramp; and that we had smoke in the cockpit. We parked away from the buildings by the grass; powered down and evacuated. After assuring the passengers were safe and well clear; I opened the left nose baggage door and white smoke billowed out. The fire crew inspected the aircraft and found no fire but did notice scorch marks and minor smoke on the bulkhead baggage compartment vertical wall. At the time of this writing; no further evaluation has been done to determine the exact cause of the seemingly unrelated events.

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.