Narrative:

Approximately 30 NM north of fof VOR on airway UA555, FL350, aircraft suddenly encountered severe turbulence, the duration lasting approximately 5 seconds. Forecast and actual flight conditions prior to the incident were clear and smooth. Captain was flying the aircraft with the #1 autoplt engaged. The fasten seat belt sign had just been turned off along with the required PA to keep seat belts fastened while seated. Due to the darkness, both pilots were observing the WX radar with one set on the 120 NM range and the other on the 240 NM range. There was no WX observed on radar and no outside visual clues to indicate any in the vicinity. 2 hours prior, the aircraft and crew had passed over the same area at FL330 en route from sju to bgi on with a smooth ride and no WX in daylight conditions. During the incident the autoplt disengaged but no excessive gain or loss of altitude was recalled. The premium flight attendant reported there were some injuries to both cabin crew and passenger. A report was made to dispatch through flight support lima and to ATC. The decision was made to continue and land at sju due to the known availability of quality medical assistance and ground support personnel there.

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Original NASA ASRS Text

Title: INFLT TURB.

Narrative: APPROX 30 NM N OF FOF VOR ON AIRWAY UA555, FL350, ACFT SUDDENLY ENCOUNTERED SEVERE TURB, THE DURATION LASTING APPROX 5 SECONDS. FORECAST AND ACTUAL FLT CONDITIONS PRIOR TO THE INCIDENT WERE CLR AND SMOOTH. CAPT WAS FLYING THE ACFT WITH THE #1 AUTOPLT ENGAGED. THE FASTEN SEAT BELT SIGN HAD JUST BEEN TURNED OFF ALONG WITH THE REQUIRED PA TO KEEP SEAT BELTS FASTENED WHILE SEATED. DUE TO THE DARKNESS, BOTH PLTS WERE OBSERVING THE WX RADAR WITH ONE SET ON THE 120 NM RANGE AND THE OTHER ON THE 240 NM RANGE. THERE WAS NO WX OBSERVED ON RADAR AND NO OUTSIDE VISUAL CLUES TO INDICATE ANY IN THE VICINITY. 2 HRS PRIOR, THE ACFT AND CREW HAD PASSED OVER THE SAME AREA AT FL330 ENRTE FROM SJU TO BGI ON WITH A SMOOTH RIDE AND NO WX IN DAYLIGHT CONDITIONS. DURING THE INCIDENT THE AUTOPLT DISENGAGED BUT NO EXCESSIVE GAIN OR LOSS OF ALT WAS RECALLED. THE PREMIUM FLT ATTENDANT RPTED THERE WERE SOME INJURIES TO BOTH CABIN CREW AND PAX. A RPT WAS MADE TO DISPATCH THROUGH FLT SUPPORT LIMA AND TO ATC. THE DECISION WAS MADE TO CONTINUE AND LAND AT SJU DUE TO THE KNOWN AVAILABILITY OF QUALITY MEDICAL ASSISTANCE AND GND SUPPORT PERSONNEL THERE.

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.