# NTSB CHI95LA097: Piper PA-32RT, N1978J, Joliet, IL, March 1, 1995 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: March 1, 1995, 17:30 local (23:30 UTC) - Place: Joliet, IL - Coordinates: 41.52008, -88.120254 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=41.5201&lon=-88.1203&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report June 29, 1995 - Report: Approved by Office Director - NTSB case key (mKey): 9846 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI95LA097 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/9846/pdf - Page: https://openairdocs.org/ntsb/CHI95LA097 ## Probable cause the failure of the number four cylinder due to a loose cylinder hold down stud. A factor in the accident was the embankment. ## 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,cylinder - failure,total (cause) - engine assembly,cylinder - loose (cause) - Forced landing, descent - emergency - On ground/water encounter with terrain/water, landing - terrain condition - drop-off/descending embankment (contributing factor) ## Analysis ACCORDING TO THE PILOT, APPROXIMATELY TEN MINUTES INTO THE FLIGHT, THE ENGINE BEGAN TO RUN ROUGH. THE PILOT STATED HE BEGAN TO TROUBLESHOOT AND EVERYTHING APPEARED NORMAL EXCEPT THE FUEL FLOW WAS LOW. AT THIS TIME HE ADVANCED THE THROTTLE, SWITCHED FUEL TANKS, AND TURNED THE FUEL BOOST PUMP ON. THE PILOT STATED HE THEN HEARD A 'BANG' FROM THE ENGINE AND ALL ENGINE POWER WAS LOST. THE PILOT MADE A FORCED LANDING ON AN ACCESS ROAD ADJACENT TO A HIGHWAY. POSTACCIDENT EXAMINATION REVEALED THE NUMBER FOUR CYLINDER HAD SEPARATED FROM THE CRANKCASE. FRACTURES OF THE CYLINDER HOLD DOWN STUDS SHOWED NO CLEAR EVIDENCE OF FATIGUE CRACKING. FRACTURES ARE REPRESENTATIVE OF OVERSTRESS SEPARATIONS. FRETTING DAMAGE WAS OBSERVED ON THE MATING CYLINDER FLANGE, CRANKCASE BOSS, AND METAL FOLDS ON THE CYLINDER FLANGE/HOLE WALL CORNERS. ## Factual narrative On March 1, 1995, at 1730 central standard time, a Piper PA-R, N1978J, registered to Lowe Automotive, St. Louis, Missouri, was substantially damaged following a loss of engine power and subsequent off-airport forced landing near Joliet, Illinois. The private pilot and one passenger reported minor injuries. The 14 CFR Part 91 flight originated in West Chicago, Illinois, at 1710 with an intended destination of Bloomington, Illinois. An IFR flight plan was filed and visual meteorological conditions prevailed at the time. According to the pilot, approximately ten minutes after departing DuPage County Airport, West Chicago, Illinois, the engine began to run rough. The pilot stated he began to troubleshoot and "everything appeared good except [the] fuel flow was low." At this time, he advanced the throttle, switched fuel tanks, and turned the fuel boost pump on. The pilot stated he then heard a "bang" from the engine and all engine power was lost. The pilot made a forced landing on an access road adjacent to a highway. While landing, the airplane hit an embankment before coming to rest. Postaccident examination revealed the number four cylinder was separated from the crankcase but still attached to the exhaust stack and ignition wires. The base of the cylinder was substantially damaged but there was no obvious damage to the inside walls of the cylinder. The bottom skirt of the number four piston was also substantially damaged. The lower left cylinder hold down stud was found completely out of the crankcase, but still in the hole of the cylinder base flange with the nut attached. Another stud, which was found at the accident site, was fractured nearly flush with the underside of the assembled nut. Both studs were sent to the NTSB Materials Laboratory, Washington, D.C., for further examination. Examination revealed the threads of the intact stud were damaged between the underside of the nut to a position corresponding to the plane of the crankcase cylinder boss when the stud is assembled to the crankcase. The Metallurgist Factual Report stated "the thread damage was as if the thread crowns had been flattened by the cylinder flange moving against this area." Examination of the other stud disclosed features indicative of an overstress separation with no evidence of preexisting cracking. A second postaccident examination of the cylinder and crankcase was done by an NTSB Metallurgist at DuPage Airport where the airplane was being stored. Examination showed no clear evidence of fatigue cracking. All fractures appeared to be representative of overstress separations. No welding repair to the crankcase was observed. Fretting damage was observed on the mating cylinder flange, crankcase boss, and metal folds on the cylinder flange/hole wall corners. (See attached Metallurgist Factual Report) ## Aircraft - Registration: [N1978J](https://openairdocs.org/deregistered/N1978J-1996-01-31), registration cancelled 1996-01-31, S/N 32R7885223 (OpenAirDocs) - Reported make and model: PIPER PA-32RT - Registry model: [Piper PA-32RT-300](https://openairdocs.org/model/piper-pa-32rt-300) (registry code 7103215) (OpenAirDocs) - Category: Airplane - Serial number: 32R-7885223 - Airframe hours: 1450 - Engines: LYCOMING IO-540-K1G5D 300 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Lowe Automotive - Airworthiness certificate: Standard, Normal - Last inspection: Annual, September 9, 1994, 72 hours before - Departed: DPA, WEST CHICAGO, IL - Destination: BMI, BLOOMINGTON, IL - Flight plan: IFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 34; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 823 total, 415 in this make and model, 724 as pilot in command, 38 in the last 90 days, 11 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Visibility: 15 statute miles - Lowest ceiling: none - Temperature: 25 °F ## 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 19950301002899A](https://openairdocs.org/incident/19950301002899A), Mar 1, 1995: Piper PA32RT300, Joliet, IL, Substantial damage. Low fuel pressure and power loss. Landed on a road. Struck embankment. NR4 cylinder separated studs had broken. (-23) aircraft was on an IFR flight plan on… 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.