Accident Overview
On November 1, 2011, at 1735 eastern daylight time, a Cessna 172N, registration N739JN, was substantially damaged during a forced landing following a partial loss of engine power while on final approach to Pompano Beach Airpark (PMP), Pompano Beach, Florida. The certificated commercial pilot and one passenger reported minor injuries. The personal flight was conducted under Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed. The flight originated from Fort Lauderdale Executive Airport (FXE), Fort Lauderdale, Florida, at 1730.
Sequence of Events
The pilot reported that during descent on final approach, the throttle control became unresponsive. Attempts to change the engine power setting yielded no response, and the engine remained at idle speed. The pilot executed a forced landing on a road, during which the airplane collided with a light post.
Post-Accident Examination
Post-accident examination by a Federal Aviation Administration inspector revealed that the fuselage collided with a light post and separated from the cabin section. The left wing outboard section broke away from the wing assembly at the wing strut. The wreckage was recovered, and a cursory engine examination found no mechanical anomalies that would have precluded normal operation. Further inspection identified that the outer throttle cable housing had separated. Movement of the throttle control did not actuate the carburetor throttle control. A review of maintenance records indicated no recent maintenance to the cable, and no anomalies were noted during the last annual inspection.
Maintenance History
Review of the aircraft and engine logbooks showed that the throttle cable had not been replaced or inspected within the preceding 2,512.9 hours. The Cessna model 172 service manual specifies on page 2-42, item J: “Engine controls and linkage—check general condition, freedom of movement through full range. Check for proper travel, security of attachment, and evidence of wear. Check friction locks for proper operation (every 50 hours).” Page 2-48 of the manual, under special inspections legends, part E, states: “Lubricate each 50 hours, these controls are not repairable and should be replaced every 1,500 hours or whenever maximum linear movement exceeds .050 inches.”