Small aircraft has wake turbulence encounter with jet aircraft.

Attributes
ACN	299676
Time
Date	199503
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : dfw
State Reference	TX
Altitude	msl bound lower : 6000 msl bound upper : 8000
Environment
Flight Conditions	VMC
Aircraft 1
Controlling Facilities	tracon : dfw tower : sfo
Make Model Name	M-20 F Executive 21
Operating Under FAR Part	Part 91
Flight Phase	cruise other
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : private
ASRS Report	299676
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	inflight encounter other
Independent Detector	other flight crewa
Resolutory Action	none taken : unable
Consequence	Other
Supplementary
Air Traffic Incident	other

Narrative:

Roughly 10-12 yrs ago I was transiting the dfw terminal area on an IFR flight to sat in a mooney 201. As I recall I was at 6000-8000 ft. Numerous aircraft, many of them heavy, were climbing to altitude and I was being routed under some of them, but more or less at right angles to their departure paths. I did not to my knowledge pass in any immediate proximity to any of the departing or climbing aircraft. In clear air we experienced a tremendous but extremely brief bump accompanied by a loud noise, almost as if the aircraft had been hit by the proverbial '2 by 4.' the flight proceeded without incident. There was no visible damage to the aircraft or change in flight characteristics. In retrospect, I have to wonder if we did not cross an area of wake turbulence at either the top or the bottom of the vortex. If the forward speed of a mooney at roughly 150 KTS were added to the opposing velocity at either the top or the bottom of the vortex as it penetrated at a 90 degree angle, I can imagine that the instantaneous resulting airspeed might be extremely high. Subsequently, I have tried to make sure that I don't get vectored directly under aircraft unless separated by several thousand ft, and have not experienced this phenomenon again.

Original NASA ASRS Text

Title: SMA HAS WAKE TURB ENCOUNTER WITH JET ACFT.

Narrative: ROUGHLY 10-12 YRS AGO I WAS TRANSITING THE DFW TERMINAL AREA ON AN IFR FLT TO SAT IN A MOONEY 201. AS I RECALL I WAS AT 6000-8000 FT. NUMEROUS ACFT, MANY OF THEM HVY, WERE CLBING TO ALT AND I WAS BEING ROUTED UNDER SOME OF THEM, BUT MORE OR LESS AT R ANGLES TO THEIR DEP PATHS. I DID NOT TO MY KNOWLEDGE PASS IN ANY IMMEDIATE PROX TO ANY OF THE DEPARTING OR CLBING ACFT. IN CLR AIR WE EXPERIENCED A TREMENDOUS BUT EXTREMELY BRIEF BUMP ACCOMPANIED BY A LOUD NOISE, ALMOST AS IF THE ACFT HAD BEEN HIT BY THE PROVERBIAL '2 BY 4.' THE FLT PROCEEDED WITHOUT INCIDENT. THERE WAS NO VISIBLE DAMAGE TO THE ACFT OR CHANGE IN FLT CHARACTERISTICS. IN RETROSPECT, I HAVE TO WONDER IF WE DID NOT CROSS AN AREA OF WAKE TURB AT EITHER THE TOP OR THE BOTTOM OF THE VORTEX. IF THE FORWARD SPD OF A MOONEY AT ROUGHLY 150 KTS WERE ADDED TO THE OPPOSING VELOCITY AT EITHER THE TOP OR THE BOTTOM OF THE VORTEX AS IT PENETRATED AT A 90 DEG ANGLE, I CAN IMAGINE THAT THE INSTANTANEOUS RESULTING AIRSPD MIGHT BE EXTREMELY HIGH. SUBSEQUENTLY, I HAVE TRIED TO MAKE SURE THAT I DON'T GET VECTORED DIRECTLY UNDER ACFT UNLESS SEPARATED BY SEVERAL THOUSAND FT, AND HAVE NOT EXPERIENCED THIS PHENOMENON AGAIN.

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.