Narrative:

We were making an approach in VMC, on profile and speed. We were visually following a B757. We tried to stay 4-5 mi behind the B757. The only evidence of any wake was at about 500 ft AGL. It was minor and momentary. At about 20 ft AGL, on speed and spooled approximately, the speed dropped off from a normal speed of 'reference +5 KTS' to 'reference -2 KTS.' I was the PNF. I called out 'reference.' the first officer immediately added power and attempted to pitch down the airplane and not respond as we would have expected, but pitched up instead. More power was added. Aircraft touched down, ballooned back up about 5 ft, then touched down again. Neither touchdown was with excessive force. The rest of the rollout and taxi to gate was uneventful. Upon postflt walkaround, evidence of a tail strike was seen. Mechanics took the aircraft OTS. We submitted to drug and alcohol tests and were removed from duty. Because the approach was a textbook approach to 20 ft, then fell apart so quickly, I believe some residual wake may have been causal.

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Original NASA ASRS Text

Title: B737-300 FO LOST AIRSPD DURING LNDG TOUCHDOWN AND BOUNCED INTO THE AIR FOR ANOTHER LNDG RESULTING IN A TAIL STRIKE AND MAINT REMOVING IT FROM SVC. FLC BELIEVE THAT THE ACFT WAS CAUGHT IN WAKE TURB OF A PRECEDING B757.

Narrative: WE WERE MAKING AN APCH IN VMC, ON PROFILE AND SPD. WE WERE VISUALLY FOLLOWING A B757. WE TRIED TO STAY 4-5 MI BEHIND THE B757. THE ONLY EVIDENCE OF ANY WAKE WAS AT ABOUT 500 FT AGL. IT WAS MINOR AND MOMENTARY. AT ABOUT 20 FT AGL, ON SPD AND SPOOLED APPROX, THE SPD DROPPED OFF FROM A NORMAL SPD OF 'REF +5 KTS' TO 'REF -2 KTS.' I WAS THE PNF. I CALLED OUT 'REF.' THE FO IMMEDIATELY ADDED PWR AND ATTEMPTED TO PITCH DOWN THE AIRPLANE AND NOT RESPOND AS WE WOULD HAVE EXPECTED, BUT PITCHED UP INSTEAD. MORE PWR WAS ADDED. ACFT TOUCHED DOWN, BALLOONED BACK UP ABOUT 5 FT, THEN TOUCHED DOWN AGAIN. NEITHER TOUCHDOWN WAS WITH EXCESSIVE FORCE. THE REST OF THE ROLLOUT AND TAXI TO GATE WAS UNEVENTFUL. UPON POSTFLT WALKAROUND, EVIDENCE OF A TAIL STRIKE WAS SEEN. MECHS TOOK THE ACFT OTS. WE SUBMITTED TO DRUG AND ALCOHOL TESTS AND WERE REMOVED FROM DUTY. BECAUSE THE APCH WAS A TEXTBOOK APCH TO 20 FT, THEN FELL APART SO QUICKLY, I BELIEVE SOME RESIDUAL WAKE MAY HAVE BEEN CAUSAL.

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.