Small aircraft encounters wake turbulence following an small transport in the traffic pattern.

Attributes
ACN	312879
Time
Date	199507
Day	Mon
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : ane
State Reference	MN
Altitude	msl bound lower : 1800 msl bound upper : 1800
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Operator	general aviation : instructional
Make Model Name	PA-28 Cherokee/Archer II/Dakota/Pillan/Warrior
Operating Under FAR Part	Part 91
Flight Phase	other ground : preflight
Flight Plan	None
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	other : unknown
Flight Phase	descent : approach landing other other
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Experience	flight time last 90 days : 25 flight time total : 350 flight time type : 50
ASRS Report	312879
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private pilot : instrument
Events
Anomaly	inflight encounter other
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted
Consequence	Other
Supplementary
Air Traffic Incident	other

Narrative:

My aircraft was a rented piper warrior (PA-28-161). Before dark that evening I had stopped at ane in blaine, mn, to drop off a passenger, and at the time of my story I was doing 3 full-stop night lndgs prior to continuation of the flight into the nighttime hours with one remaining passenger (which I am glad I did -- the runways look different at night and I have not done enough night flying to feel proficient enough to carry passenger without the practice). As I did one of my takeoff's another aircraft entered the pattern, and as I turned around onto downwind I estimate I was 1/2 mi behind him. I did not make note of the type of the other aircraft, but it carried the proliferation of flashing lights characteristic of a king air or similar model. I held an airspeed of about 80 KTS, and I had planned to extend my downwind to lengthen the distance between us so that there would be no conflict during the landing. However, I was apparently too close during the downwind because as I flew my downwind I experienced a sudden roll to the left of about 30 degrees which I was able to counteract with a strong (less than full deflection) aileron input, and then after correcting the roll the same thing happened one more time. It was a calm night and the only explanation for the sudden roll is wake turbulence. The situation was neither life-threatening nor even frightening, but it taught me respect for pattern spacing. In the future, I will space myself further back. I learn something every time I fly, and this is not the only thing I learned on this trip. Every pilot is taught in ground school about wake turbulence, and it is valuable training, making us aware of a very real hazard which can occur not just during landing but any time we follow another aircraft. Callback conversation with reporter revealed the following information: reporter was contacted for the structured callback of the wake turbulence study. He was amazed that even though he was taking precaution to remain well behind the twin, he still encountered the wake. He feels he learned a great deal through this experience.

Original NASA ASRS Text

Title: SMA ENCOUNTERS WAKE TURB FOLLOWING AN SMT IN THE TFC PATTERN.

Narrative: MY ACFT WAS A RENTED PIPER WARRIOR (PA-28-161). BEFORE DARK THAT EVENING I HAD STOPPED AT ANE IN BLAINE, MN, TO DROP OFF A PAX, AND AT THE TIME OF MY STORY I WAS DOING 3 FULL-STOP NIGHT LNDGS PRIOR TO CONTINUATION OF THE FLT INTO THE NIGHTTIME HRS WITH ONE REMAINING PAX (WHICH I AM GLAD I DID -- THE RWYS LOOK DIFFERENT AT NIGHT AND I HAVE NOT DONE ENOUGH NIGHT FLYING TO FEEL PROFICIENT ENOUGH TO CARRY PAX WITHOUT THE PRACTICE). AS I DID ONE OF MY TKOF'S ANOTHER ACFT ENTERED THE PATTERN, AND AS I TURNED AROUND ONTO DOWNWIND I ESTIMATE I WAS 1/2 MI BEHIND HIM. I DID NOT MAKE NOTE OF THE TYPE OF THE OTHER ACFT, BUT IT CARRIED THE PROLIFERATION OF FLASHING LIGHTS CHARACTERISTIC OF A KING AIR OR SIMILAR MODEL. I HELD AN AIRSPD OF ABOUT 80 KTS, AND I HAD PLANNED TO EXTEND MY DOWNWIND TO LENGTHEN THE DISTANCE BTWN US SO THAT THERE WOULD BE NO CONFLICT DURING THE LNDG. HOWEVER, I WAS APPARENTLY TOO CLOSE DURING THE DOWNWIND BECAUSE AS I FLEW MY DOWNWIND I EXPERIENCED A SUDDEN ROLL TO THE L OF ABOUT 30 DEGS WHICH I WAS ABLE TO COUNTERACT WITH A STRONG (LESS THAN FULL DEFLECTION) AILERON INPUT, AND THEN AFTER CORRECTING THE ROLL THE SAME THING HAPPENED ONE MORE TIME. IT WAS A CALM NIGHT AND THE ONLY EXPLANATION FOR THE SUDDEN ROLL IS WAKE TURB. THE SIT WAS NEITHER LIFE-THREATENING NOR EVEN FRIGHTENING, BUT IT TAUGHT ME RESPECT FOR PATTERN SPACING. IN THE FUTURE, I WILL SPACE MYSELF FURTHER BACK. I LEARN SOMETHING EVERY TIME I FLY, AND THIS IS NOT THE ONLY THING I LEARNED ON THIS TRIP. EVERY PLT IS TAUGHT IN GND SCHOOL ABOUT WAKE TURB, AND IT IS VALUABLE TRAINING, MAKING US AWARE OF A VERY REAL HAZARD WHICH CAN OCCUR NOT JUST DURING LNDG BUT ANY TIME WE FOLLOW ANOTHER ACFT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR WAS CONTACTED FOR THE STRUCTURED CALLBACK OF THE WAKE TURB STUDY. HE WAS AMAZED THAT EVEN THOUGH HE WAS TAKING PRECAUTION TO REMAIN WELL BEHIND THE TWIN, HE STILL ENCOUNTERED THE WAKE. HE FEELS HE LEARNED A GREAT DEAL THROUGH THIS EXPERIENCE.

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.