# NTSB FTW99LA032: Piper PA32-300, N2881U, New Iberia, LA, November 20, 1998 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: November 20, 1998, 08:30 local (14:30 UTC) - Place: New Iberia, LA - Coordinates: 29.999727, -91.809928 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=29.9997&lon=-91.8099&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report February 16, 2001 - Report: Approved by Office Director - NTSB case key (mKey): 45349 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW99LA032 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/45349/pdf - Page: https://openairdocs.org/ntsb/FTW99LA032 ## Probable cause The mechanic's failure to properly torque the connecting rod's bolt and nut during engine overhaul. A factor was the lack of suitable terrain for the forced landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - mech failure/malf, climb - to cruise - engine assembly,connecting rod - failure - engine assembly,connecting rod bolt - undertorqued (cause) - maintenance,overhaul,major - improper, other maintenance personnel (cause) - Forced landing, emergency descent/landing - On ground/water collision with object, landing - roll - terrain condition - none suitable (contributing factor) - object - tree(s) - object - fence ## Analysis The airplane's engine experienced a catastrophic failure during cruise climb. The airplane impacted a tree and fence during the forced landing near a residential area. The airplane's maintenance records revealed that the engine had been overhauled on August 20, 1991, and had accumulated 1,423.49 hours since then. Examination of the engine revealed that the number 6 connecting rod had failed in 'overload' and was a 'secondary failure.' One of the connecting rod's bolt and nut assemblies was then examined. The nut was cut and split in the threaded area. The first two threads of the nut, adjacent to the contact surface, were found 'stripped.' Additionally, 'no scuff marks were observed' on the copper plating in the undamaged portion of the nut contact surface. It was determined that the two stripped threads were the result of the nut backing off during operation, and the lack of a scuff mark on the nut's contact surface was the result of it being improperly torqued during installation. ## Factual narrative On November 20, 1998, at 0830 central standard time, a Piper PA32-300 airplane, N2881U, owned and operated by the pilot, was substantially damaged during a forced landing following a loss of engine power near New Iberia, Louisiana. The non-instrument rated private pilot, who was the sole occupant, received minor injuries. Instrument meteorological conditions prevailed and a flight plan was not filed for the Title 14 CFR Part 91 personal flight. The flight originated from the Acadiana Regional Airport, New Iberia, Louisiana, at 0815, and was destined for New Orleans, Louisiana. During a telephone interview conducted by the NTSB investigator-in-charge (IIC), the pilot stated that he departed with a special VFR clearance and was climbing through 2,500 feet when he heard a "fairly loud explosion." The pilot stated that at first, he thought the engine noise sounded similar to a backfire. He noticed a power loss and turned back toward the Acadiana Regional Airport. A few minutes after the first explosion he heard a second "explosion that shook the airplane and sent a blanket of oil over the windshield." The pilot secured the engine and executed a forced landing to a field. During the landing roll, the aircraft crossed a road, impacted a tree with the left wing and the horizontal stabilizer, slid into a fence and came to a stop upright. An FAA inspector examined the airplane and reported that the right main landing gear, four feet of the left outboard wing, and the tip of the left horizontal stabilizer were separated from the airplane. The six seat, fixed landing gear airplane was powered by a Lycoming IO-540-K165 engine, S/N L-19502-48A. The airframe had accumulated a total of 3,392 hours at the time of the accident. The last annual inspection of the aircraft was completed on June 5, 1998. The last engine overhaul was completed on August 20, 1991. Since the last engine overhaul, the engine had accumulated 1,423.49 hours. Review of the maintenance records by the NTSB IIC did not reveal evidence of any uncorrected maintenance discrepancies. The Lycoming IO-540-K165 engine, S/N L-19502-48A, was inspected at the Textron Lycoming factory in Williamsport, Pennsylvania, under the supervision of an FAA inspector. Upon disassembly of the engine, the number 6 connecting rod was found fractured. After examining the connecting rod fracture surface, the failure was determined by the Lycoming metallurgist to be a "secondary failure resulting from overload." One of the number 6 connecting rod's bolt and nut assembly was then examined by the metallurgist. The nut was cut and split in the threaded area. Examination of the nut revealed that the first two threads, adjacent to the contact surface, were "stripped." Additionally, "no scuff marks were observed" on the copper plating in the undamaged portion of the nut contact surface. The metallurgist at the Lycoming factory determined that the two stripped threads indicated that the nut had backed off during operation of the engine, and that the lack of scuff marks on the contact surface copper plating indicated that the nut was not properly torqued during installation. See the enclosed metallurgist's report for details of the examination. ## Aircraft - Registration: [N2881U](https://openairdocs.org/deregistered/N2881U-2001-10-02), registration cancelled 2001-10-02, S/N 32-7940179 (OpenAirDocs) - Reported make and model: Piper PA32-300 - Registry model: [Piper PA-32-300](https://openairdocs.org/model/piper-pa-32-300) (registry code 7103212) (OpenAirDocs) - Category: Airplane - Serial number: 32-7940179 - Airframe hours: 3392 - Engines: Lycoming IO-540-K165 300 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Kenneth P. Daigle - Airworthiness certificate: Standard, Normal - Last inspection: Annual, June 5, 1998, 47 hours before - Departed: ARA, NEW IBERIA, LA - Destination: NEW, NEW ORLEANS, LA ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 46; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 1,550 total, 800 in this make and model, 1,550 as pilot in command, 50 in the last 90 days, 25 in the last 30 days ## Weather - Conditions: Instrument (IMC), Day - Wind: calm - Visibility: 1.25 statute miles - Lowest ceiling: 100 ft broken - Temperature: 66 °F, dew point 66 °F - Altimeter: 30.00 inHg - Observed at: ARA, 3 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 19981120031979A](https://openairdocs.org/incident/19981120031979A), Nov 20, 1998: Piper PA32300, Iberia, LA, Substantial damage. Pilot reported engine trouble and the acft mde an emergency landing. (-23) the pilot experienced total engine failure, accompanied by total oil loss, while in… 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.