Narrative:

On jan/thu/99, at approximately XA00 local time the captain and I were called to report for duty at bradley, ct, to fly a trip to philadelphia, PA, to pick up cargo and deliver it to columbus, oh. The flight was to be conducted under part 91, then part 135 on the second leg. The WX was IMC with mixed slushy snow. A WX briefing was obtained and an IFR flight plan was filed with an alternate airport. The aircraft was brushed clean of all snow, no ice was present on the aircraft. All checklists were performed and all indications were normal. We departed the field and all anti and deice equipment was used. All indications were normal and flight controls normal until at 5000 ft MSL and 210 KIAS. At that point the aircraft began to shake violently (mostly elevator) and aircraft control became an issue. We declared an emergency about 20 seconds into the shaking after checking engine instruments and pressurization (both were normal). Vector for an ILS back to bradley were given. Aircraft shaking ceased under 200 KIAS, although vibration was still present. ILS and landing were accomplished successfully and uneventfully. Upon landing it was noted that the aircraft had accumulated about 1/4 inch of clear ice on some unprotected areas (ie, nose and tip tanks). This is normal and does not affect aircraft controllability. Maintenance was performed on the aircraft and it was found that several 'bushings' in the tail were worn excessively giving the elevator play measured in excess of 3 inches. Why this was not caught on previous inspections is unknown.

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Original NASA ASRS Text

Title: HF20 HAD ELEVATOR FLUTTER ABOVE 200 KIAS.

Narrative: ON JAN/THU/99, AT APPROX XA00 LCL TIME THE CAPT AND I WERE CALLED TO RPT FOR DUTY AT BRADLEY, CT, TO FLY A TRIP TO PHILADELPHIA, PA, TO PICK UP CARGO AND DELIVER IT TO COLUMBUS, OH. THE FLT WAS TO BE CONDUCTED UNDER PART 91, THEN PART 135 ON THE SECOND LEG. THE WX WAS IMC WITH MIXED SLUSHY SNOW. A WX BRIEFING WAS OBTAINED AND AN IFR FLT PLAN WAS FILED WITH AN ALTERNATE ARPT. THE ACFT WAS BRUSHED CLEAN OF ALL SNOW, NO ICE WAS PRESENT ON THE ACFT. ALL CHKLISTS WERE PERFORMED AND ALL INDICATIONS WERE NORMAL. WE DEPARTED THE FIELD AND ALL ANTI AND DEICE EQUIP WAS USED. ALL INDICATIONS WERE NORMAL AND FLT CTLS NORMAL UNTIL AT 5000 FT MSL AND 210 KIAS. AT THAT POINT THE ACFT BEGAN TO SHAKE VIOLENTLY (MOSTLY ELEVATOR) AND ACFT CTL BECAME AN ISSUE. WE DECLARED AN EMER ABOUT 20 SECONDS INTO THE SHAKING AFTER CHKING ENG INSTS AND PRESSURIZATION (BOTH WERE NORMAL). VECTOR FOR AN ILS BACK TO BRADLEY WERE GIVEN. ACFT SHAKING CEASED UNDER 200 KIAS, ALTHOUGH VIBRATION WAS STILL PRESENT. ILS AND LNDG WERE ACCOMPLISHED SUCCESSFULLY AND UNEVENTFULLY. UPON LNDG IT WAS NOTED THAT THE ACFT HAD ACCUMULATED ABOUT 1/4 INCH OF CLR ICE ON SOME UNPROTECTED AREAS (IE, NOSE AND TIP TANKS). THIS IS NORMAL AND DOES NOT AFFECT ACFT CONTROLLABILITY. MAINT WAS PERFORMED ON THE ACFT AND IT WAS FOUND THAT SEVERAL 'BUSHINGS' IN THE TAIL WERE WORN EXCESSIVELY GIVING THE ELEVATOR PLAY MEASURED IN EXCESS OF 3 INCHES. WHY THIS WAS NOT CAUGHT ON PREVIOUS INSPECTIONS IS UNKNOWN.

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.