Mcdonnell Douglas MD-83 accident near Miami, Florida, October 3, 1993
On October 3, 1993 at about 7:55 pm local time, a Mcdonnell Douglas MD-83, registered N9YTHR, was substantially damaged in an accident near Miami, Florida. It was a flight of an unrecorded kind under foreign airline rules (Part 129). 1 person was seriously injured and 1 person had minor injuries; 80 others were unhurt. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
THE FAILURE OF THE WATER HEATER RELAY AND THE OVERPRESSURE RELIEF VALVE TO OPERATE PROPERLY. IN ADDITION, THE DESIGN OF THE RELIEF VALVE WAS INADEQUATE IN THAT IT ALLOWED THE O-RING TO MIGRATE FROM ITS NORMAL POSITION PREVENTING THE VALVE FROM OPENING.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- October 3, 1993 · about 7:55 pm local time
- Place
- Miami, Florida
- Type
- Accident
- Injuries
- 1 person was seriously injured and 1 person had minor injuries; 80 others were unhurt.
- Weather
- visual conditions (good weather)
- Aircraft
- Mcdonnell Douglas MD-83
- Registration
- N9YTHR · no longer on the register · serial 49568
- Damage
- Substantial damage
- Flight
- Flight of an unrecorded kind · foreign airline rules (Part 129)
The NTSB's narrative final · quoted from the NTSB record
THE WATER HEATER IN THE FORWARD GALLEY EXPLODED. EXAMINATION REVEALED THAT THE CONTACTS OF THE WATER HEATER RELAY, WHICH, WHEN ENERGIZED, PROVIDES ELECTRICAL POWER TO THE 3 HEATER ELEMENTS, WERE ROUGH, RAGGED, DISCOLORED, AND SHOWED EXCESSIVE EROSION. ACCORDING TO THE MANUFACTURER, WHEN A RELAY EXCEEDS ITS LIFETIME, IT IS POSSIBLE FOR EROSION AND WEAR ON THE SURFACE TO CAUSE THE CONTACTS TO STICK IN THE CLOSED POSITION. IN ADDITION, THE PRESSURE RELIEF VALVE, WHICH IS DESIGNED TO CRACK AT 65 PSI, WAS TESTED TO 300 PSI WITHOUT CRACKING. UPON DISASSEMBLY, THE O-RING WAS FOUND TO HAVE MIGRATED FROM ITS NORMAL LOCATION INTO THE LOWER VALVE BODY WHERE IT LODGED BETWEEN THE INSIDE DIAMETER AND THE HEAD OF THE POPPET. IN THIS CONDITION, THE O-RING PRESENTED A COMPLETED FLOW BLOCKAGE AND PREVENTED THE PRESSURE RELIEF VALVE FROM OPENING.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
Pilot
- Certificate: airline transport pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 8,500 hours in all; 4,200 in this make and model; 200 in the last 90 days; 65 in the last 30 days; 220 as pilot in command
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 14,657 hours
- Last inspection: continuous airworthiness programme, September 12, 1993; 162 hours since
- Maximum gross weight: 160,000 lb
- Seats: 138
- Landing gear: retractable
- Engine: P&W JT8D-219 (turbojet); 0 hours total
The flight
- Destination: TBPB Barbados OF
- Flight plan: IFR
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 330° at 5 knots
- Visibility: 7 statute miles
- Sky: overcast at 14,000 ft; scat at 9,000 ft
- Temperature: 79°F (26°C), dew point 73°F (23°C)
- Altimeter: 30.00 inHg
- Observation at 7:50 pm from MIA, 100 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | 1 | 4 | |
| Passengers | 76 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.