# NTSB FTW86MA030: Boeing 737-2H4, N86SW, Dallas, TX, January 3, 1986

- Type: NTSB incident investigation
- Classification: Incident · No injuries · Major investigation · Final report
- Date: January 3, 1986, 07:22 local (13:22 UTC)
- Place: Dallas, TX
- Coordinates: 32.830432, -96.850929 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=32.8304&lon=-96.8509&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 44 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 22165
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW86MA030
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/22165/pdf
- Page: https://openairdocs.org/ntsb/FTW86MA030

## Sequence of events

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

- Airframe/component/system failure/malfunction, takeoff - roll/run
  - engine installation,suspension mounts - failure,partial (cause)
  - engine installation,suspension mounts - fatigue (cause)
  - engine installation,suspension mounts - separation (cause)
  - engine installation,suspension mounts - overload (cause)
  - engine installation,suspension mounts - undertorqued (cause)
  - maintenance,installation - improper, company maintenance personnel (cause)
  - airport facilities,runway/landing area condition - rough/uneven (contributing factor)

## Analysis

THIS INCIDENT OCCURRED WHEN THE NO. 2 ENGINE EXPERIENCED AN AFT ENGINE MOUNT CONE BOLT FAILURE AND THE SUBSEQUENT FAILURE OF THE SECONDARY SUPPORT LINK (STAINLESS STEEL CABLE). THE FAILURE OF BOTH AFT ENGINE SUPPORT ASSEMBLIES DURING THE TAKEOFF ROLL ALLOWED THE AFT SECTION OF THE ENG TO HANG DOWN TO WITHIN 4' OF THE GROUND. AS A RESULT, THE NO.2 THRUST REVERSER ACTUATOR ASSEMBLY DRUG THE RUNWAY ON ROTATION. IN ADDITION, ONE LEADING EDGE FLAP AND THE FORWARD ENGINE FAIRING WERE SLIGHTLY DAMAGED. THE ACFT SUBSEQUENTLY RETURNED TO THE ARPT AND LANDED WITHOUT FURTHER INCIDENT. METALLURGICAL EXAMINATION OF THE CONE BOLT REVEALED THAT IT FAILED AS A RESULT OF FATIGUE, MOST PROBABLY DUE TO IMPROPER INSTALLATION OF THE BOLT, SPECIFICALLY, THAT IT WAS UNDER TORQUED WHEN THE OPERATOR RE-INSTALLED THE ENG. THE SAFETY CABLE FAILED AS A RESULT OF OVERSTRESS, PROBABLY INDUCED WHEN THE ACFT ENCOUNTERED A ROUGH STRETCH OF RUNWAY DURING THE TAKEOFF ROLL.

## Aircraft

- Registration: [N86SW](https://openairdocs.org/deregistered/N86SW-2013-03-19), registration cancelled 2013-03-19, S/N 22827, built 1982 (OpenAirDocs)
- Reported make and model: BOEING 737-2H4
- Registry model: [Boeing 737-2H4](https://openairdocs.org/model/boeing-737-2h4) (registry code 138448C) (OpenAirDocs)
- Registry engine: [Pratt & Whitney JT8D-17 series](https://openairdocs.org/engine/pratt-whitney-jt8d-17-series) (registry code 52049, turbo-jet) (OpenAirDocs)
- Category: Airplane
- Serial number: 22827
- Airframe hours: 12341
- Engines: P&W JT-8D-9A 14500 lbs thrust turbo fan
- Damage: Minor damage
- Flight: Part 121
- Registered owner: Southwest Airlines Co.
- Airworthiness certificate: Standard, Transport
- Last inspection: AAIP, December 28, 1985, 77 hours before
- Departed: DAL
- Destination: AUS, AUSTIN, TX
- Flight plan: IFR
- Airport: DAL, Love Field, runway 31R, 7,753 × 150 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 45; airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 13,050 total, 8,550 in this make and model, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 37 °F, dew point 30 °F
- Altimeter: 30.00 inHg
- Observed at: DAL

## 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 19860103068529I](https://openairdocs.org/incident/19860103068529I), Jan 3, 1986: Boeing 7372H4, Dallas, TX, Substantial damage. NR2 engine aft mount cone bolt broke on rotation. Aft portion of engine dropped down. Safe landing.

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.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.