Narrative:

This was prompted by the recent request in callback for wake turbulence information. It occurred in 1988 and made a sufficiently significant impression that I noted it in my logbook. If it doesn't meet your recency requirements, please discard. 2 of my children and I were on route from bed to orf. Visibility was unlimited. There was a strong flow of air from the southwest. 1 daughter was in the right rear seat and the other was in the right front seat. About 10 mi southwest of jfk on V-1 at 8000 ft, the controller informed me of 747 traffic that would be climbing through my altitude, south of my position, and warned 'caution, wake turbulence.' I knew I would be below the path of the 747, was concerned with the flow of air from the southwest, but assumed any turbulence would be below my altitude when I crossed the area. Nonetheless, I tightened my seat belt and asked my daughters to do the same. Unbeknownst to me, my daughter in the rear was not wearing her headset and did not hear my request. The flight had been quite smooth. When we hit the wake turbulence, the plane experienced a dramatic downward motion -- the impact being a sudden, fierce jolt. No rolling tendency was experienced. My daughter in the rear seat hit the ceiling of the aircraft with sufficient force to cause a large scalp bruise. Both my front seat daughter and I were restrained by our seat belts. There is no doubt in my mind that the cause of this incident was wake turbulence. My heading at the time was about 220 degrees and I estimate the course of the 747 to have been about 280 degrees. In retrospect, it seems to me I was in a precarious position no matter what I did (except for a 180 degree turn). Better sensitivity to this situation by the controller might have resulted in climb instructions to the 747 which would have crossed my course below my altitude or behind me -- which would have avoided this incident.

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Original NASA ASRS Text

Title: SMA ENCOUNTERS WAKE TURB FROM B-747.

Narrative: THIS WAS PROMPTED BY THE RECENT REQUEST IN CALLBACK FOR WAKE TURB INFO. IT OCCURRED IN 1988 AND MADE A SUFFICIENTLY SIGNIFICANT IMPRESSION THAT I NOTED IT IN MY LOGBOOK. IF IT DOESN'T MEET YOUR RECENCY REQUIREMENTS, PLEASE DISCARD. 2 OF MY CHILDREN AND I WERE ON RTE FROM BED TO ORF. VISIBILITY WAS UNLIMITED. THERE WAS A STRONG FLOW OF AIR FROM THE SW. 1 DAUGHTER WAS IN THE R REAR SEAT AND THE OTHER WAS IN THE R FRONT SEAT. ABOUT 10 MI SW OF JFK ON V-1 AT 8000 FT, THE CTLR INFORMED ME OF 747 TFC THAT WOULD BE CLBING THROUGH MY ALT, S OF MY POS, AND WARNED 'CAUTION, WAKE TURB.' I KNEW I WOULD BE BELOW THE PATH OF THE 747, WAS CONCERNED WITH THE FLOW OF AIR FROM THE SW, BUT ASSUMED ANY TURB WOULD BE BELOW MY ALT WHEN I CROSSED THE AREA. NONETHELESS, I TIGHTENED MY SEAT BELT AND ASKED MY DAUGHTERS TO DO THE SAME. UNBEKNOWNST TO ME, MY DAUGHTER IN THE REAR WAS NOT WEARING HER HEADSET AND DID NOT HEAR MY REQUEST. THE FLT HAD BEEN QUITE SMOOTH. WHEN WE HIT THE WAKE TURB, THE PLANE EXPERIENCED A DRAMATIC DOWNWARD MOTION -- THE IMPACT BEING A SUDDEN, FIERCE JOLT. NO ROLLING TENDENCY WAS EXPERIENCED. MY DAUGHTER IN THE REAR SEAT HIT THE CEILING OF THE ACFT WITH SUFFICIENT FORCE TO CAUSE A LARGE SCALP BRUISE. BOTH MY FRONT SEAT DAUGHTER AND I WERE RESTRAINED BY OUR SEAT BELTS. THERE IS NO DOUBT IN MY MIND THAT THE CAUSE OF THIS INCIDENT WAS WAKE TURB. MY HDG AT THE TIME WAS ABOUT 220 DEGS AND I ESTIMATE THE COURSE OF THE 747 TO HAVE BEEN ABOUT 280 DEGS. IN RETROSPECT, IT SEEMS TO ME I WAS IN A PRECARIOUS POS NO MATTER WHAT I DID (EXCEPT FOR A 180 DEG TURN). BETTER SENSITIVITY TO THIS SIT BY THE CTLR MIGHT HAVE RESULTED IN CLB INSTRUCTIONS TO THE 747 WHICH WOULD HAVE CROSSED MY COURSE BELOW MY ALT OR BEHIND ME -- WHICH WOULD HAVE AVOIDED THIS INCIDENT.

Data retrieved from NASA's ASRS site as of August 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.