# NTSB NYC06LA179: Cessna 172N, N4792D, Pompton Lakes, NJ, July 14, 2006 - Type: NTSB accident investigation - Classification: Accident · Fatal · Limited investigation · Final report - Date: July 14, 2006, 17:45 local (21:45 UTC) - Place: Pompton Lakes, NJ - Coordinates: 41.016666, -74.279998 - Nearby events: https://openairdocs.org/map.md?lat=41.0167&lon=-74.2800&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed, report July 25, 2007 - Report: Approved by Office Director - Parties: Lycoming Engines, Cessna Aircraft Company, FAA/FSDO - NTSB case key (mKey): 64112 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC06LA179 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/64112/pdf - Page: https://openairdocs.org/ntsb/NYC06LA179 ## Probable cause Improper maintenance of the throttle shaft, which resulted in a partial loss of engine power during cruise flight, and subsequent impact with trees during a forced landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - mech failure/malf, cruise - throttle/power lever,linkage - not secured - maintenance - improper, company maintenance personnel (cause) - Forced landing, descent - emergency - In flight collision with object, emergency descent/landing - object - tree(s) ## Analysis The accident flight was the first flight after the airplane's most recent annual inspection was completed. During the flight, the pilot reported that he had no throttle control. The pilot further stated that the engine rpm was 1,400, and the airplane was losing altitude. The pilot attempted to execute a forced landing to an access road; however, the airplane struck trees and a postcrash fire ensued. Examination of the wreckage revealed that the throttle body portion of the carburetor remained attached to the engine, and the cotter pin was missing from the throttle lever locknut. The throttle lever locknut was partially backed-off its stop. In addition, the throttle lever was loose, and the serrations on the throttle shaft stop were disengaged from the serrations on the throttle lever. Review of maintenance records revealed that during the annual inspection, the throttle shaft bushings and shaft assembly were noted as worn, and were subsequently removed and replaced. The mechanic that performed the work stated that he recalled installing a throttle shaft bushing and a throttle shaft, but did not recall a cotter pin missing. Review of a Cessna service manual revealed instructions and diagrams to secure the locknut with a cotter pin. No other preimpact mechanical malfunctions were observed. ## Factual narrative On July 14, 2006, about 1745 eastern daylight time, a Cessna 172N, N4792D, was destroyed during a forced landing and collision with trees, after experiencing a loss of engine power in cruise flight near Pompton Lakes, New Jersey. The certificated private pilot was fatally injured. Visual meteorological conditions prevailed for the flight that departed Essex County Airport (CDW), Caldwell, New Jersey, about 1700. No flight plan was filed for the local personal flight conducted under 14 CFR Part 91. According to recorded radio communications from the CDW air traffic control (ATC) tower, the pilot contacted the CDW tower prior to the accident. The pilot stated that the airplane was north of the Wanaque Reservoir, and that he had no throttle control. The pilot further stated that the engine rpm was 1,400, and that the airplane was losing altitude. The air traffic controller then asked the pilot if he was declaring an emergency, and the pilot replied yes. The controller asked the pilot his intentions, and the pilot replied that he was crossing Route 287, at 700 feet, and losing altitude. The pilot further stated that he was going to try and divert to Lincoln Park, New Jersey, but did not think that he would make it. The controller then stated that if the pilot could find an area large enough to land, to please advise him, and the controller would notify the police. No further communications were received from the pilot. The pilot attempted a forced landing to an access road; however, the airplane struck trees and a postcrash fire ensued. The accident occurred during the hours of daylight. The wreckage was located approximately 41 degrees, 01.00 minutes north latitude, and 74 degrees, 16.80 minutes west longitude. The pilot held a private pilot certificate, with a rating for airplane single engine land. His most recent Federal Aviation Administration (FAA) third class medical certificate was issued on April 12, 2005. The pilot's logbook was not recovered; however, review of FAA records and the airplane operator's rental history, revealed that the pilot had accumulated an estimated total flight experience of approximately 340 hours. According to the rental history, the pilot had flown approximately 4 hours during the 30 days preceding the accident, and 9 hours during the 90 days preceding the accident. All of the pilot's flight experience, from January 2005, was in the same make and model as the accident airplane. The wreckage was examined at a salvage facility on July 26, 2006. The engine was found removed from the airframe. The throttle body portion of the carburetor remained attached to the engine, and the cotter pin was missing from the throttle lever locknut. The throttle lever locknut was partially backed-off its stop. In addition, the throttle lever was loose, and the serrations on the throttle shaft stop were disengaged from the serrations on the throttle lever. The starter, oil pump, magneto drive, oil filter, baffling, propeller, exhaust system, and firewall were removed from the engine. The magnetos were destroyed by fire. The oil filter was opened, and no metallic contamination was observed. The valve covers were removed from the engine, and oil was observed throughout the engine. The top sparkplugs were removed, their electrodes were intact, and gray in color; except for the number one and three sparkplugs, which were oil soaked. The crankshaft was rotated via the oil pump accessory gear drive, using a socket wrench. Crankshaft, camshaft, and valve train continuity were confirmed throughout the engine, and thumb compression was attained on all cylinders. Flight control continuity was confirmed from the left and right wing aileron bellcranks, to the wing roots where the cables were cut during recovery. Continuity was also confirmed from the elevator and rudder, to where they were cut about the mid-cabin area, and then continued to the control "T" and rudder pedals. The elevator trim actuator jackscrew measured approximately 1.35 inches, which corresponded to 4 to 5 degrees nose-down pitch. Review of the maintenance records revealed that the accident flight was the first flight after the airplane's most recent annual inspection was completed. At the time of the inspection, the airplane had accumulated about 10,675 hours of operation. During the annual inspection, the throttle shaft bushings and shaft assembly were noted as worn, and were subsequently removed and replaced. After the accident, the mechanic that performed the annual inspection was interviewed via telephone. The mechanic stated that he recalled installing a throttle shaft bushing and a throttle shaft, but did not recall a cotter pin missing. Review of a Cessna "Model 172 Series Service Manual" revealed instructions and diagrams to secure the locknut with a cotter pin. An autopsy was performed on the pilot by the Passaic County Regional Medical Examiner's Office, Newark, New Jersey. Toxicological testing was conducted on the pilot at the FAA Toxicology Accident Research Laboratory, Oklahoma City, Oklahoma. Review of the toxicology report revealed: "...TRIAMTERENE present in Blood TRIAMTERENE present in Urine TRIAMTERENE present in Liver..." Review of the pilot's most recent application for an FAA third class medical certificate revealed that he reported using Triamterene for high blood pressure. The reported weather at CDW, at 1753, was: wind from 170 degrees at 8 knots; visibility 10 miles; scattered clouds at 6,500 feet; temperature 86 degrees F; dew point 66 degrees F; altimeter 29.96 inches/Hg. ## Aircraft - Registration: [N4792D](https://openairdocs.org/deregistered/N4792D-2008-09-16), registration cancelled 2008-09-16, S/N 17272361, built 1979 (OpenAirDocs) - Reported make and model: Cessna 172N - Registry model: [Cessna 172N](https://openairdocs.org/model/cessna-172n) (registry code 2072434) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 17272361 - Airframe hours: 10675 - Engines: Lycoming O-320 160 horsepower reciprocating - Damage: Destroyed - Fire: On-Ground - Flight: Personal, Part 91 - Operator: Mac Dan Aviation - Registered owner: M D Aeronautical Corp - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 1, 2006, 0 hours before - Departed: CDW, Caldwell, NJ - Destination: CDW - Airport: CDW, Essex County Airport ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 74; injuries: fatal; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; last flight review March 1, 2005; seat: left; toxicology performed; flight hours: 340 total, 9 in the last 90 days, 4 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 140° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 86 °F, dew point 66 °F - Altimeter: 29.95 inHg - Observed at: CDW, 10 nm away ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20060714022259A](https://openairdocs.org/incident/20060714022259A), Jul 14, 2006: Cessna 172N, Pompton Lakes, NJ, Destroyed, 1 fatal. (-23) At approx 1740 pilot called mayday, stating loss of engine power and that aircraft was losing altitude. Pilot attempted landing on road which is part of… ## Other investigations on N4792D (1) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB NYC87LA083](https://openairdocs.org/ntsb/NYC87LA083), Feb 7, 1987: Cessna 172 (N4792D), Caldwell, NJ, substantial damage From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.