Cessna 172M accident near San Juan, Puerto Rico, July 25, 2012
On July 25, 2012 at about 6:20 pm local time, a 1976 Cessna 172M, registered N73115, was substantially damaged in an accident during approach (VFR pattern final) near San Juan, Puerto Rico (Fernando Luis Ribas Dominicci airport). It was a personal flight under general aviation rules (Part 91). 1 person was killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
Maintenance personnel’s improper lubrication of the right direct aileron control cable and failure to detect the severe corrosion of the cable during a maintenance inspection, which resulted in the in-flight failure of the cable, the pilot’s subsequent inability to maintain aircraft control, and the airplane’s impact with terrain.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 25, 2012 · about 6:20 pm local time
- Place
- San Juan, Puerto Rico · Fernando Luis Ribas Dominicci · map
- Type
- Accident
- Injuries
- 1 person was killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 172M, built 1976 · all 172Ms on the register
- Registration
- N73115 · no longer on the register · serial 17267271
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
About 4 minutes before the accident, the pilot advised an air traffic controller that an aileron cable had broken but that he was continuing to the airport to land. Security video and eyewitness reports revealed that the airplane was at low altitude and appeared to be maintaining level flight until it banked right, descended, and impacted water near the airport in a right-wing-down attitude. A postaccident examination of the wreckage indicated that all of the airplane's flight control cables were lubricated except for a fractured section of aileron control direct cable near the doorpost pulley, which was likely not properly lubricated. Most of the cable strands and the doorpost pulley and bearing exhibited severe corrosion near the fracture. When manipulated by hand, the pulley bearing would not rotate due to the corrosion. Analysis of the cable, doorpost pulley, and an exemplar cable from a similar make and model aircraft that had been flown in similar atmospheric conditions (in what is considered a severe corrosion zone) revealed moderate to severe corrosion. It is likely that, during the airplane's maintenance inspection 6 months before the accident, the mechanic failed to detect the corroded cable due to the difficulty in visually seeing the cable. It is also likely that the doorpost pulley's failure to rotate resulted in tension on the right aileron control cable, which subsequently caused it to fail due to the severe corrosion. The aircraft manufacturer's maintenance manual for the airplane gives specific instructions for lubricating and inspecting flight control cables and pulleys every 600 hours or 12 months, whichever comes first, including, in part, examining the cables for corrosion and the pulleys to ensure smooth rotation. After the accident, the manufacturer produced a video emphasizing the importance of properly examining and lubricating the cables.
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
What happened, in order
- Sys/Comp malf/fail (non-power) during approach (VFR pattern final) defining event
- Loss of control in flight during approach (VFR pattern final)
- Collision with terrain or object (not controlled flight into terrain) during uncontrolled descent
The NTSB's findings
- cause Aircraft › Aircraft systems › Flight control system › Aileron control system › Fatigue/wear/corrosion
- cause Personnel issues › Task performance › Maintenance › Scheduled/routine maintenance › Maintenance personnel
- cause Aircraft › Aircraft systems › Flight control system › Aileron control system › Malfunction
- Environmental issues › Task environment › Physical workspace › Access to equipment/controls › Contributed to outcome
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › (general) › Attain/maintain not possible
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 1,175 hours in all; 500 in this make and model
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: left
- Injury: fatal
The aircraft
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-320-E2D (piston); 0 hours total
The flight
- Departed from: TJAB Arecibo PR at 5:50 pm
- Destination: TJIG San Juan PR
- Flight plan: VFR
- Runway 09, 5,542 ft by 100 ft
Weather at the time
- Light: daylight
- Wind: from 110° at 8 knots
- Visibility: 10 statute miles
- Sky: scat at 4,000 ft
- Temperature: 90°F (32°C), dew point 75°F (24°C)
- Altimeter: 30.03 inHg
- Observation at 5:22 pm from TJIG
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
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.