# NTSB MIA92IA020: Boeing 727-31, N839TW, Gulf Of Mexico, November 2, 1991

- Type: NTSB incident investigation
- Classification: Incident · No injuries · Incident investigation · Final report
- Date: November 2, 1991, 10:17 local (15:17 UTC)
- Place: Gulf Of Mexico
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 118 uninjured
- Status: Completed, report May 3, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 33001
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA92IA020
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/33001/pdf
- Page: https://openairdocs.org/ntsb/MIA92IA020

## Probable cause

THE OVERFILLING OF THE FORWARD LAVATORY DURING SERVICING AND THE FAILURE TO REPLACE THE FILL/RINSE LINE CAP AFTER SERVICING BY THE GROUND SERVICE PERSONNEL WHICH RESULTED IN THE LAVATORY VENTING FLUID THROUGH THE FILL/RINSE LINE DURING FLIGHT AND THE SUBSEQUENT ICE FORMATION AND INGESTION OF ICE INTO NUMBER THREE ENGINE.

## Sequence of events

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

- Loss of engine power(total) - mech failure/malf, cruise - normal
  - water and waste system - failure,partial
  - maintenance,service of aircraft/equipment - improper, ground personnel (cause)
  - complacency, ground personnel (cause)
  - water and waste system - missing
  - water and waste system - siphoning
  - water and waste system - ice
  - engine assembly - foreign object damage

## Analysis

GROUND PERSONNEL SERVICED FORWARD LAVATORY JUST BEFORE FLIGHT. FLIGHT ATTENDANT STATED FLUID WAS VISIBLE IN UPPER TOILET AREA OF FORWARD LAVATORY AFTER SERVICING INDICATING IT HAD BEEN OVERFILLED. ENROUTE NUMBER 3 ENGINE FAILED AND WAS SHUTDOWN. FLIGHT DIVERTED TO MIAMI. ON ARRIVAL A BLUE STREAK WAS FOUND ON THE RIGHT SIDE OF THE AIRCRAFT BEGINNING AT THE FORWARD LAVATORY SERVICE DOOR AND ENDING AT THE INLET TO NUMBER 3 ENGINE. THE FORWARD LAVATORY SERVICE DOOR WAS FOUND CLOSED AND THE FILL/RINSE LINE CAP WAS MISSING WHEN THE DOOR WAS OPENED. THE FILL/RINSE LINE CHECK VALVE WAS FOUND STUCK OPEN. WHEN A CAP WAS INSTALLED ON THE LINE NO LEAKAGE OCCURRED. THE LAVATORY DRAIN LINE DID NOT LEAK. NUMBER 3 ENGINE HAD SUSTAINED FAN DAMAGE DUE TO INGESTION OF SOFT MATTER.

## Aircraft

- Registration: [N839TW](https://openairdocs.org/deregistered/N839TW-2012-07-24), registration cancelled 2012-07-24, S/N 18904, built 1965 (OpenAirDocs)
- Reported make and model: BOEING 727-31
- Registry model: [Boeing 727-31](https://openairdocs.org/model/boeing-727-31) (registry code 1384010) (OpenAirDocs)
- Registry engine: [Pratt & Whitney JT8D-1](https://openairdocs.org/engine/pratt-whitney-jt8d-1) (registry code 52044, turbo-jet) (OpenAirDocs)
- Category: Airplane
- Serial number: 18904
- Engines: P&W JT8D 14000 lbs thrust turbo fan
- Damage: Minor damage
- Flight: Part 121
- Operator: Private Jet Expeditions
- Registered owner: Tran World Airlines
- Airworthiness certificate: Standard, Transport
- Last inspection: AAIP, January 2, 2000
- Departed: EWR, NEWARK, NJ
- Destination: MMUN, CANCUN, OF
- Flight plan: IFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 37; airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 8,700 total, 4,200 in this make and model, 6,800 as pilot in command, 150 in the last 90 days, 45 in the last 30 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 30 statute miles
- Lowest ceiling: none
- Temperature: -65 °F
- Altimeter: 29.00 inHg

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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