# NTSB MKC85IA131: Lockheed L-1011, N31013, St. Louis, MO, June 11, 1985

- Type: NTSB incident investigation
- Classification: Incident · No injuries · Incident investigation · Final report
- Date: June 11, 1985, 11:04 local (16:04 UTC)
- Place: St. Louis, MO
- Coordinates: 38.740596, -90.350105 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=38.7406&lon=-90.3501&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 219 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 33872
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MKC85IA131
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/33872/pdf
- Page: https://openairdocs.org/ntsb/MKC85IA131

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Airframe/component/system failure/malfunction, approach - iaf to faf/outer marker (ifr)
  - flight control,flap attachment - fatigue (cause)
  - flight control,flap attachment - separation (cause)

## Analysis

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.

## Aircraft

- Registration: [N31013](https://openairdocs.org/deregistered/N31013-2013-06-27), registration cancelled 2013-06-27, S/N 193B-1035, built 1973 (OpenAirDocs)
- Reported make and model: LOCKHEED L-1011
- Registry model: [Lockheed L-1011-385-1](https://openairdocs.org/model/lockheed-l-1011-385-1) (registry code 5265010) (OpenAirDocs)
- Registry engine: [Rolls-Royce RB-211-22 series](https://openairdocs.org/engine/rolls-royce-rb-211-22-series) (registry code 54554, turbo-fan) (OpenAirDocs)
- Category: Airplane
- Serial number: 193B-1035
- Airframe hours: 31195
- Engines: Rolls-Royce RB-211-22 45000 lbs thrust turbo fan
- Damage: Minor damage
- Fire: In-Flight
- Flight: Part 121
- Registered owner: Trans World Airways
- Airworthiness certificate: Standard, Normal
- Departed: BOS, BOSTON, MA
- Destination: STL, ST.LOUIS, MO
- Flight plan: IFR
- Airport: STL, St. Louis

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; airline transport; airplane ratings: multi-engine land, single-engine land; medical: unknown, unknown; seat: left

## Weather

- Conditions: Instrument (IMC), Day
- Wind: 270° at 11 knots
- Visibility: 25 statute miles
- Lowest ceiling: 700 ft overcast
- Temperature: -0 °F, dew point -0 °F
- Altimeter: 29.00 inHg
- Observed at: STL, 5 nm away

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Incident 19850611027729I](https://openairdocs.org/incident/19850611027729I), Jun 11, 1985: Lkheed 1011385115, St Louis, MO, Minor damage. Aircraft lost the right outboard nr 3 flap vane on approach. Maintenance determining cause of failure.

## Other investigations on N31013 (4)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB LAX90IA101](https://openairdocs.org/ntsb/LAX90IA101), Feb 19, 1990: Lockheed L-1011-385-1 (N31013), Los Angeles, CA, incident, minor damage. Probable cause: THE FAILURE OF THE WELD HOLDING THE SLIP JOINT TO THE PNEUMATIC DUAL COMPENSATOR FROM THE NO. 2 ENGINE.
- [NTSB MKC83IA115](https://openairdocs.org/ntsb/MKC83IA115), May 25, 1983: Lockheed L-1011-385-1 (N31013), St. Louis, MO, incident, minor damage
- [NTSB MKC76AK058](https://openairdocs.org/ntsb/MKC76AK058), Jun 1, 1976: Lockheed L-1011 (N31013), Salina, KS, substantial damage
- [NTSB LAX76IL023](https://openairdocs.org/ntsb/LAX76IL023), Oct 2, 1975: Lockheed 1011 (N31013), Philadelphia, PA, incident, no damage

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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