Sikorsky SK-70 accident near Marathon, Florida, November 3, 1989
On November 3, 1989 at about 2:30 am local time, a Sikorsky SK-70 (helicopter), registered N23576, was destroyed in an accident near Marathon, Florida. It was a public-use flight under general aviation rules (Part 91). 1 person was killed and 2 people had minor injuries; 3 others were unhurt. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
FAILURE OF THE PILOT TO MAINTAIN THE PROPER ALTITUDE OVER THE OCEAN WATER. FACTORS RELATED TO THE ACCIDENT WERE: CONTINUED OPERATION OF THE HELICOPTER WITH A KNOWN PARTIAL DEFICIENCY OF THE RADIO ALTIMETER/WARNING SYSTEM, DARKNESS, THE PILOT'S LACK OF VISUAL PERCEPTION, FAILURE OF THE COPILOT TO ADEQUATELY MONITOR THE HELICOPTER'S ALTITUDE ABOVE THE WATER, AND INSUFFICIENT MANAGEMENT STANDARDS TO IDENTIFY INORDINATE FLIGHT RISKS.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- November 3, 1989 · about 2:30 am local time
- Place
- Marathon, Florida · map
- Type
- Accident
- Injuries
- 1 person was killed and 2 people had minor injuries; 3 others were unhurt.
- Weather
- visual conditions (good weather)
- Aircraft
- Sikorsky SK-70
- Registration
- N23576 · no longer on the register · serial 81-23576
- Damage
- Destroyed
- Flight
- Public-use flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE HELICOPTER WAS ON A NIGHT LAW ENFORCEMENT MISSION OVR THE OCEAN NR MARATHON, FL. AFTER TKOF, THE PIC NOTED THE RADARALTIMETER NEEDLE, WHICH ACTIVATED THE LOW ALT WARNING, WAS NOT FUNCTIONAL, THOUGH THE DIGITAL DISPLAY & COPLT'S RADAR ALTIMETER WERE OPERATING NORMALLY. AFTER ENTERING THE MISSION AREA, THE PIC BGN RANDOM MNVRS WITH THE ALT VARYING BTN 200 & 300 FT ABV THE WATER. THERE WAS AN ESTD 1000 FT OVC SKY COND WITH NO VISIBLE HRZN. BOTH PLTS WERE WEARING NIGHT VISION GOGGLES. THE COPLT OPERATED THE SEARCH LIGHT & WAS TO MONITOR THE INSTS. WHILE MNVRG TO KEEP A BOAT IN VIEW, THE HELICOPTER BGN DSCNDG & CONTACTED THE WATER. IMMEDIATELY, THE CABIN FILLED WITH WATER. ALL OF THE OCCUPANTS EGRESSED SUCCESSFULLY FM THE HELICOPTER, EXCEPT THE COPLT, WHO PRESUMABLY DROWNED. THE PIC & 2 OF THE OTR CREWMEMBERS WERE NOT INJURED; THE REMAINING 2 RCVD MINOR INJURIES. AN AGENCY OPNS HANDBOOK DISCUSSED HAZARDS/INCIDENTS, BUT NO MISSION RISK ASSESSMENT PROGRAM WAS IN PLACE FOR MANAGEMENT TO ADEQUATELY IDENTIFY THE LEVEL OF RISK ASSOCIATED WITH THE OPN.
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; instrument: helicopter; rotorcraft: helicopter
- Flight time: 4,758 hours in all; 490 in this make and model; 73 in the last 90 days; 31 in the last 30 days; 4,503 as pilot in command
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 2,016 hours
- Last inspection: continuous airworthiness programme, September 24, 1989; 2 hours since
- Maximum gross weight: 20,250 lb
- Seats: 7
- Landing gear: fixed
- Engine: Ge T700-GE-700 (turboshaft); 0 hours total
The flight
- Departed from: HST Homestead Afb FL
- Destination: HST
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: night, dark
- Wind: at 9 knots
- Visibility: 10 statute miles
- Sky: broken clouds at 1,000 ft; not recorded
- Temperature: 75°F (24°C), dew point 0°F (-18°C)
- Altimeter: 29.00 inHg
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | 2 | 3 |
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.