Serious incident Lockheed L-1011 TriStar N31013, Tuesday 11 June 1985

You can contribute by submitting additional or updated information.

Date:	Tuesday 11 June 1985
Time:	11:04 LT
Type:	Lockheed L-1011 TriStar
Owner/operator:	Trans World Airlines - TWA
Registration:	N31013
MSN:	193B-1035
Total airframe hrs:	31195 hours
Engine model:	Rolls-Royce RB-211-22
Fatalities:	Fatalities: 0 / Occupants: 219
Other fatalities:	0
Aircraft damage:	Minor
Category:	Serious incident
Location:	St. Louis, MO - United States of America
Phase:	Approach
Nature:	Passenger - Scheduled
Departure airport:	Boston, MA (KBOS)
Destination airport:	St.louis, MO (KSTL)
Investigating agency:	NTSB
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
WHILE ON AN IFR APPROACH TO LAND AT STL AND THE PLT INITIATED FLAPS. THE NO.3 OUTBOARD FLAP VANE SEPARATED FROM ITS MOUNTING AND FELL TO THE GROUND. UPON SEPARATION THE FLAP VANE STRUCK THE LEADING EDGE OF THE TRAILING EDGE FLAP KNOCKING A HOLE IN THE SKIN. THE SUBSEQUENT LANDING WAS UNEVENTFUL. EXAMINATION OF THE FLAP VANE ATTACH FITTING REVEALED IT FAILED IN FATIGUE FOLLOWED BY AN OVERLOAD SEPARATION. THERE HAVE BEEN 14 RECORDED CASES OF FAILURE OF THE FLAP VANE ATTACH FITTINGS WITH 9 REPORTED SEPARATIONS FROM THE AIRCRAFT.

Probable Cause:

Accident investigation: