Narrative:

2 yrs ago I should have written to you for your requested wake turbulence report. I find the reports very useful. This is my payback, I hope our experience will help others. My wife had recently earned her single engine license to fly our cherokee 160. She was in the left seat while I worked the radios, both boys were in the back. It was a pleasant ride home from the cabin up north and we had been with flight following the 200 mi trip down. The wind was blowing out of the southeast at 10 KTS giving us a headwind for our 170 degree direction of flight. ATC had us descend to 3500 ft from our cruising altitude to stay below the TCA. We complied and after a short time canceled service because flying cloud airport was in sight, 15 mi away. We changed frequency and were cleared for landing runway 18. Simultaneously a B747 passed in front of us for a runway 11R landing into msp: full flaps and landing gear in sight. We estimated the airplane to be 3-5 mi out and above us, a good setup for wake turbulence. She initiated a descent and was coming out of 2500 ft when the turbulence hit several mins later. Boom! It sounded like we hit a solid wall and it was over that just as quickly. The impact jarred my headset loose and we all strained against our seatbelts hitting the ceiling. The strain jarred the door open! Fortunately for us we made a safe landing and 'learned' first hand to take aggressive actions to avoid wake turbulence. Callback conversation with reporter revealed the following information: the reporter was acting as the radio operator and generally assisting his wife who was flying a piper cherokee 160 with a total of 4 people on board. He said that as they were approaching fcm from the north they saw a B747 on approach to msp's runway 11R. He said that he and his wife discussed the possibility of hitting the B747's wake as they passed below it on their approach to runway 18. His wife started a descent out of 3500 ft to get well below the B747, but as they departed 2500 ft they felt a sudden increase of pressure and heard a 'boom' and all of the occupants hit their heads against the cabin ceiling even though everyone was wearing their seat belts. Also he said that the cabin door flew open. He said that he closed the cabin door and informed the controller about the encounter and assured that everyone was uninjured. He attempted to talk to a TRACON supervisor later, he said, but the supervisor seemed to be busy so he decided not to bother him. The reporter mentioned that he did not have the aircraft inspected and he only checked the door to insure proper operation. Apparently, the door would open quite easily because he mentioned that on a later flight a passenger bumped it and it opened although it had been latched.

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Original NASA ASRS Text

Title: A PA28 HIT THE WAKE OF A B747 AS THE 2 ACFT CROSSED PATHS WHILE ON APCH TO 2 DIFFERENT ARPTS. THE PA28'S DOOR POPPED OPEN UNDER THE SHOCK OF THE VIOLENT ENCOUNTER.

Narrative: 2 YRS AGO I SHOULD HAVE WRITTEN TO YOU FOR YOUR REQUESTED WAKE TURB RPT. I FIND THE RPTS VERY USEFUL. THIS IS MY PAYBACK, I HOPE OUR EXPERIENCE WILL HELP OTHERS. MY WIFE HAD RECENTLY EARNED HER SINGLE ENG LICENSE TO FLY OUR CHEROKEE 160. SHE WAS IN THE L SEAT WHILE I WORKED THE RADIOS, BOTH BOYS WERE IN THE BACK. IT WAS A PLEASANT RIDE HOME FROM THE CABIN UP N AND WE HAD BEEN WITH FLT FOLLOWING THE 200 MI TRIP DOWN. THE WIND WAS BLOWING OUT OF THE SE AT 10 KTS GIVING US A HEADWIND FOR OUR 170 DEG DIRECTION OF FLT. ATC HAD US DSND TO 3500 FT FROM OUR CRUISING ALT TO STAY BELOW THE TCA. WE COMPLIED AND AFTER A SHORT TIME CANCELED SVC BECAUSE FLYING CLOUD ARPT WAS IN SIGHT, 15 MI AWAY. WE CHANGED FREQ AND WERE CLRED FOR LNDG RWY 18. SIMULTANEOUSLY A B747 PASSED IN FRONT OF US FOR A RWY 11R LNDG INTO MSP: FULL FLAPS AND LNDG GEAR IN SIGHT. WE ESTIMATED THE AIRPLANE TO BE 3-5 MI OUT AND ABOVE US, A GOOD SETUP FOR WAKE TURB. SHE INITIATED A DSCNT AND WAS COMING OUT OF 2500 FT WHEN THE TURB HIT SEVERAL MINS LATER. BOOM! IT SOUNDED LIKE WE HIT A SOLID WALL AND IT WAS OVER THAT JUST AS QUICKLY. THE IMPACT JARRED MY HEADSET LOOSE AND WE ALL STRAINED AGAINST OUR SEATBELTS HITTING THE CEILING. THE STRAIN JARRED THE DOOR OPEN! FORTUNATELY FOR US WE MADE A SAFE LNDG AND 'LEARNED' FIRST HAND TO TAKE AGGRESSIVE ACTIONS TO AVOID WAKE TURB. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR WAS ACTING AS THE RADIO OPERATOR AND GENERALLY ASSISTING HIS WIFE WHO WAS FLYING A PIPER CHEROKEE 160 WITH A TOTAL OF 4 PEOPLE ON BOARD. HE SAID THAT AS THEY WERE APCHING FCM FROM THE N THEY SAW A B747 ON APCH TO MSP'S RWY 11R. HE SAID THAT HE AND HIS WIFE DISCUSSED THE POSSIBILITY OF HITTING THE B747'S WAKE AS THEY PASSED BELOW IT ON THEIR APCH TO RWY 18. HIS WIFE STARTED A DSCNT OUT OF 3500 FT TO GET WELL BELOW THE B747, BUT AS THEY DEPARTED 2500 FT THEY FELT A SUDDEN INCREASE OF PRESSURE AND HEARD A 'BOOM' AND ALL OF THE OCCUPANTS HIT THEIR HEADS AGAINST THE CABIN CEILING EVEN THOUGH EVERYONE WAS WEARING THEIR SEAT BELTS. ALSO HE SAID THAT THE CABIN DOOR FLEW OPEN. HE SAID THAT HE CLOSED THE CABIN DOOR AND INFORMED THE CTLR ABOUT THE ENCOUNTER AND ASSURED THAT EVERYONE WAS UNINJURED. HE ATTEMPTED TO TALK TO A TRACON SUPVR LATER, HE SAID, BUT THE SUPVR SEEMED TO BE BUSY SO HE DECIDED NOT TO BOTHER HIM. THE RPTR MENTIONED THAT HE DID NOT HAVE THE ACFT INSPECTED AND HE ONLY CHKED THE DOOR TO INSURE PROPER OP. APPARENTLY, THE DOOR WOULD OPEN QUITE EASILY BECAUSE HE MENTIONED THAT ON A LATER FLT A PAX BUMPED IT AND IT OPENED ALTHOUGH IT HAD BEEN LATCHED.

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.