Cessna 550 accident near Marathon, Florida, July 22, 2006
On July 22, 2006 at about 4:30 pm local time, a Cessna 550, registered N466SS, was substantially damaged in an accident near Marathon, Florida (The Florida Keys Marathon Arpt airport). It was an executive or corporate flight under general aviation rules (Part 91). No one was hurt; 4 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The separation for undetermined reasons of the stud (P/N 6541204-5) which secures the main landing gear actuator assembly side brace to the main landing gear outer cylinder, allowing partial collapse of the right main landing gear while taxiing after landing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 22, 2006 · about 4:30 pm local time
- Place
- Marathon, Florida · The Florida Keys Marathon Arpt · map
- Type
- Accident
- Injuries
- No one was hurt; 4 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 550 · all 550s on the register
- Registration
- N466SS · no longer on the register · serial 550-0626
- Damage
- Substantial damage
- Flight
- Executive or corporate flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
After takeoff the landing gear retracted normally and the flight proceeded to the destination airport. While descending from 19,000 to 15,000 feet near the destination airport, a sound was heard that a passenger thought was a lightning strike. The flight leveled off at 15,000 feet, and the only discrepancy the pilot noted was the failure of the No. 1 communication transceiver to transmit. The flight continued to the destination airport and during normal extension of the landing gear, the pilot "noticed an extra clunk" sound. All landing gears were indicating down and locked and the airplane was landed uneventfully. While taxiing to the ramp, the right wing dropped. He secured the airplane, and noted the right main landing gear was displaced outboard. Marks from the right main landing gear tire were noted leading off the runway onto the taxiway, and a stud (P/N 6541204-5), which secures the main landing gear actuator assembly side brace to the main landing gear outer cylinder, was not in position and was not located for the right main landing gear. Examination of the actuator assembly attach stud tapered hole of the right main landing gear outer cylinder (P/N 5541320-6) revealed no unusual markings and the inside diameter was within limits.
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: commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 8,475 hours in all; 75 in the last 90 days; 40 in the last 30 days
- Last flight review: July 1, 2006
- Medical certificate: Class 1 (without waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 3,676 hours
- Last inspection: continuous airworthiness programme, May 1, 2006
- Maximum gross weight: 13,300 lb
- Seats: 11
- Landing gear: retractable
- Engine: Pratt & Whitney JT15D-4 (turbofan); 0 hours total
The flight
- Departed from: KCWS Conway AR at 2:30 pm
- Destination: KMTH Marathon FL
- Flight plan: IFR
- Runway 25, 5,008 ft by 100 ft
Weather at the time
- Light: daylight
- Wind: from 200° at 8 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 90°F (32°C), dew point 73°F (23°C)
- Altimeter: 30.03 inHg
- Observation at 4:53 pm from KMTH
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 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.