Narrative:

Smooth flight from islip, ny, to orlando, fl, on feb/xx/98. Approach control vectored us to localizer runway 17 (mco) to follow a company B757 on a visual approach. Due to hazy conditions we advised that we had the runway environment for runway 17 mco, but did not see the B757 preceding us clearly enough to maintain wake separation. Approach cleared us on a visual approach, but did not tell us to follow the B757 visually. I noted on TCASII that our separation was 4 1/2 mi from the B757. Approach had directed us to maintain 170 KIAS until glosi intersection. I was slowing to 165 KIAS to provide 5 mi separation when we hit a short cycle (1-2 seconds) moderate to almost severe wake turbulence. It felt like a hard landing. There was an almost simultaneous upwash and downwash, with little sustained positive or negative accelerations either laterally or horizontally. I reduced speed further to approach reference speed and flew above GS to a normal landing. Aircraft and passenger were not hurt or damaged. Callback conversation with reporter revealed the following information: reporter participated in the structured callback program. Reporter was surprised to encounter any wake as the descending aircraft in front of his was in sight, crossing his flight path, and was in a steep descent. Because he was in a steep descent his wake was stronger because full flaps had to be used for such a steep approach. Turbulence was short lived, but felt like a hard landing. No damage or passenger complaints. Next time the reporter would take a delay vector or slow down if he thought the B757 were to be a threat with wake turbulence.

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Original NASA ASRS Text

Title: A B737-200 FOLLOWING A B757-200 ENCOUNTERS WAKE TURB WHILE DSNDING INTO MCO, FL.

Narrative: SMOOTH FLT FROM ISLIP, NY, TO ORLANDO, FL, ON FEB/XX/98. APCH CTL VECTORED US TO LOC RWY 17 (MCO) TO FOLLOW A COMPANY B757 ON A VISUAL APCH. DUE TO HAZY CONDITIONS WE ADVISED THAT WE HAD THE RWY ENVIRONMENT FOR RWY 17 MCO, BUT DID NOT SEE THE B757 PRECEDING US CLRLY ENOUGH TO MAINTAIN WAKE SEPARATION. APCH CLRED US ON A VISUAL APCH, BUT DID NOT TELL US TO FOLLOW THE B757 VISUALLY. I NOTED ON TCASII THAT OUR SEPARATION WAS 4 1/2 MI FROM THE B757. APCH HAD DIRECTED US TO MAINTAIN 170 KIAS UNTIL GLOSI INTXN. I WAS SLOWING TO 165 KIAS TO PROVIDE 5 MI SEPARATION WHEN WE HIT A SHORT CYCLE (1-2 SECONDS) MODERATE TO ALMOST SEVERE WAKE TURB. IT FELT LIKE A HARD LNDG. THERE WAS AN ALMOST SIMULTANEOUS UPWASH AND DOWNWASH, WITH LITTLE SUSTAINED POSITIVE OR NEGATIVE ACCELERATIONS EITHER LATERALLY OR HORIZLY. I REDUCED SPD FURTHER TO APCH REF SPD AND FLEW ABOVE GS TO A NORMAL LNDG. ACFT AND PAX WERE NOT HURT OR DAMAGED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR PARTICIPATED IN THE STRUCTURED CALLBACK PROGRAM. RPTR WAS SURPRISED TO ENCOUNTER ANY WAKE AS THE DSNDING ACFT IN FRONT OF HIS WAS IN SIGHT, XING HIS FLT PATH, AND WAS IN A STEEP DSCNT. BECAUSE HE WAS IN A STEEP DSCNT HIS WAKE WAS STRONGER BECAUSE FULL FLAPS HAD TO BE USED FOR SUCH A STEEP APCH. TURB WAS SHORT LIVED, BUT FELT LIKE A HARD LNDG. NO DAMAGE OR PAX COMPLAINTS. NEXT TIME THE RPTR WOULD TAKE A DELAY VECTOR OR SLOW DOWN IF HE THOUGHT THE B757 WERE TO BE A THREAT WITH WAKE TURB.

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.