A B757 descending in ZTL airspace got into a severe vibration that felt like aircraft was coming apa...

Attributes
ACN	429854
Time
Date	199903
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : atl
State Reference	GA
Altitude	msl bound lower : 13000 msl bound upper : 18000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Navigation In Use	Other
Flight Phase	descent other
Route In Use	arrival other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Experience	flight time last 90 days : 200 flight time total : 20000 flight time type : 3000
ASRS Report	429854
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Experience	flight time last 90 days : 200 flight time total : 3000 flight time type : 80
ASRS Report	429861
Events
Anomaly	aircraft equipment problem : critical altitude deviation : excursion from assigned altitude non adherence : far
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	none taken : insufficient time none taken : unable
Supplementary
Air Traffic Incident	Pilot Deviation other

Narrative:

On climb to FL310 from FL290, leg dca to atl, aircraft got into a severe harmonic vertical vibration that felt like aircraft was coming apart. Great anxiety of flight attendant and passenger. I had to go back to cabin after descent to FL240 and vibration ended. Visual inspection of wings, talked to scared passenger. Back in cockpit, flight attendant in cockpit asked me to make another PA from first class microphone. Came back in, talking to company and flight attendant when first officer said macey at 13000 ft. He was briefing the arrival. I thought he had received the clearance since we wanted to slow down and descend early in case vibration came back. I took control of aircraft, dialed in 13000 on mode control panel and began descent. Around 18000 ft, ZTL said 'understand you are going to cross macey at 13000 ft.' we said 'roger.' I do not believe we were cleared to descend as first officer was on ATC frequency while I was talking to company and flight attendant. We were on ATC priority handling and it was time to descend but I think we never received ATC clearance. Right elevator power control actuator bushing and bolt were worn, etc, which caused the severe vibration. Supplemental information from acn 429861: epilogue: after inspection of the elevator, maintenance found the right elevator bushing worn past limits, hence the vibration.

Original NASA ASRS Text

Title: A B757 DSNDING IN ZTL AIRSPACE GOT INTO A SEVERE VIBRATION THAT FELT LIKE ACFT WAS COMING APART. R ELEVATOR PWR CTL ACTUATOR BUSHING AND BOLT WERE WORN, WHICH CAUSED THE VIBRATION.

Narrative: ON CLB TO FL310 FROM FL290, LEG DCA TO ATL, ACFT GOT INTO A SEVERE HARMONIC VERT VIBRATION THAT FELT LIKE ACFT WAS COMING APART. GREAT ANXIETY OF FLT ATTENDANT AND PAX. I HAD TO GO BACK TO CABIN AFTER DSCNT TO FL240 AND VIBRATION ENDED. VISUAL INSPECTION OF WINGS, TALKED TO SCARED PAX. BACK IN COCKPIT, FLT ATTENDANT IN COCKPIT ASKED ME TO MAKE ANOTHER PA FROM FIRST CLASS MIKE. CAME BACK IN, TALKING TO COMPANY AND FLT ATTENDANT WHEN FO SAID MACEY AT 13000 FT. HE WAS BRIEFING THE ARR. I THOUGHT HE HAD RECEIVED THE CLRNC SINCE WE WANTED TO SLOW DOWN AND DSND EARLY IN CASE VIBRATION CAME BACK. I TOOK CTL OF ACFT, DIALED IN 13000 ON MODE CTL PANEL AND BEGAN DSCNT. AROUND 18000 FT, ZTL SAID 'UNDERSTAND YOU ARE GOING TO CROSS MACEY AT 13000 FT.' WE SAID 'ROGER.' I DO NOT BELIEVE WE WERE CLRED TO DSND AS FO WAS ON ATC FREQ WHILE I WAS TALKING TO COMPANY AND FLT ATTENDANT. WE WERE ON ATC PRIORITY HANDLING AND IT WAS TIME TO DSND BUT I THINK WE NEVER RECEIVED ATC CLRNC. R ELEVATOR PWR CTL ACTUATOR BUSHING AND BOLT WERE WORN, ETC, WHICH CAUSED THE SEVERE VIBRATION. SUPPLEMENTAL INFO FROM ACN 429861: EPILOGUE: AFTER INSPECTION OF THE ELEVATOR, MAINT FOUND THE R ELEVATOR BUSHING WORN PAST LIMITS, HENCE THE VIBRATION.

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.

A B757 descending in ZTL airspace got into a severe vibration that felt like aircraft was coming apart. Right elevator power control actuator bushing and bolt were worn, which caused the vibration.