# NTSB NYC06IA143: Cessna 172S, N2138W, Lawrence, MA, June 6, 2006 - Type: NTSB incident investigation - Classification: Incident · No injuries · Incident investigation · Final report - Date: June 6, 2006, 19:30 local (23:30 UTC) - Place: Lawrence, MA - Coordinates: 42.717224, -71.123336 - Nearby events: https://openairdocs.org/map.md?lat=42.7172&lon=-71.1233&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report August 30, 2007 - Report: Approved by Office Director - Parties: McCauley Textron, FAA/FSDO - NTSB case key (mKey): 63867 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC06IA143 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/63867/pdf - Page: https://openairdocs.org/ntsb/NYC06IA143 ## Probable cause Foreign object damage to the leading edge of the propeller blade, which resulted in fatigue cracking and subsequent blade failure. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Propeller failure/malfunction, missed approach (ifr) - propeller system/accessories,blade - foreign object damage (cause) - propeller system/accessories,blade - fatigue - propeller system/accessories,blade - fractured - Loss of engine power(total) - nonmechanical, missed approach (ifr) - engine shutdown - intentional, pilot in command(cfi) - Forced landing, emergency descent/landing - terrain condition - runway ## Analysis The commercial pilot was conducting a practice missed approach under instruction, when a propeller blade separated. The flight instructor took control of the airplane and shut down the engine to prevent further damage. He then made a Mayday call and glided the airplane to a successful runway landing. A postflight examination of the airplane revealed that the propeller blade was separated about 12 inches from the center of the hub. Metallurgical examination of the remaining fracture face revealed fatigue cracking that emanated from an indentation at the blade's leading edge. The fatigue crack propagated through approximately 50 percent of the fracture face, and beyond that, there was a band of overstress cracking. There was no evidence of corrosion, and a chemical analysis of the propeller blade revealed that the hardness and chemical composition of the blade met the requirements of the applicable engineering drawing. The flight instructor stated that during the airplane's preflight inspection, both he and the commercial pilot visually inspected the propeller blade, and ran their hands along the leading and trailing edges with no anomalies noted. The most recent maintenance inspection of the propeller occurred about 1 month before the incident. ## Factual narrative On June 6, 2006, about 1930 eastern daylight time, a Cessna 172S, N2138W, incurred minor damage when a propeller blade separated during a missed approach at Lawrence Municipal Airport (LWM), Lawrence, Massachusetts. The certificated flight instructor and the certificated commercial pilot (under instruction) were not injured. Visual meteorological conditions prevailed. The local flight was operated on an instrument flight rules flight plan from Mansfield Municipal Airport (1B9), Mansfield, Massachusetts, and was conducted under 14 CFR Part 91. According to the flight instructor, the flight was a proficiency check for the commercial pilot. The commercial pilot had just flown the VOR RWY 23 approach, and had initiated a missed approach 1/2 mile from the runway due to traffic landing in the opposite direction. Passing through 1,700 feet, a "loud pop" was heard and the airplane began to shake violently. The flight instructor immediately took control of the airplane and shut down the engine to prevent further damage. He then made a Mayday call with his intentions, and glided the airplane to a landing on runway 32. A postflight examination of the airplane revealed that a McCauley Propeller Systems fixed-pitch propeller blade, part number 1A170E/JHA7660, serial number XH23030, had separated about 12 inches from the center of the hub. The flight instructor also noted that during the airplane's preflight inspection, both he and the commercial pilot visually inspected the propeller blade, and ran their hands along the leading and trailing edges with no anomalies noted. According to maintenance records, the most recent 100-hour inspection of the propeller blade was on May 10, 2006, about 53 operating hours before the incident. No anomalies were noted. The remainder of the separated propeller blade was forwarded to the Safety Board for metallurgical examination. According to the Materials Laboratory Factual Report, the fracture was oriented in a chordwise direction, and there were crack arrest lines along the fracture face, typical of a fatigue crack, emanating from an indentation at the blade's leading edge. The crack propagated through approximately 50 percent of the fracture face. Another crack arrest band was noted beyond the first area, which had fibrous features typical of an overstress separation. There was no mention of corrosion in the report. A chemical analysis of the propeller blade at Cessna Aircraft Company revealed that the hardness and chemical composition of the blade met the requirements of the applicable engineering drawing. ## Aircraft - Registration: [N2138W](https://openairdocs.org/aircraft/N2138W), registered now, S/N 172S9561, built 2003 (OpenAirDocs) - Reported make and model: Cessna 172S - Registry model: [Cessna 172S](https://openairdocs.org/model/cessna-172s) (registry code 2072439) (OpenAirDocs) - Registry engine: [Lycoming IO-360-L2A](https://openairdocs.org/engine/lycoming-io-360-l2a) (registry code 41597, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 172S9561 - Airframe hours: 1623 - Engines: Lycoming IO-360 180 horsepower reciprocating - Damage: Minor damage - Flight: Instructional, Part 91 - Operator: King Aviation - Registered owner: Kelley B Dineen, LLC - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, May 1, 2007, 53 hours before - Departed: 1B9, Mansfield, MA - Destination: 1B9, Mans, MA - Flight plan: IFR - Airport: LWM, Lawrence Municipal, runway 32, 3,901 × 100 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Other flight crew; age 23; injuries: none; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; last flight review March 21, 2006; seat: right; flight hours: 1,070 total, 550 in this make and model, 974 as pilot in command, 220 in the last 90 days, 85 in the last 30 days, 7 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 90° at 7 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 64 °F, dew point 55 °F - Altimeter: 30.04 inHg - Observed at: LWM ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Incident 20060606011229I](https://openairdocs.org/incident/20060606011229I), Jun 6, 2006: Cessna 172S, Lawrence, MA, Minor damage. (-23) While practicing missed approaches at (lwm) N2138W, a CE-172-S had a propeller blade separation of one blade 12" from the center of the hub. The aircraft… ## Other investigations on N2138W (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 GAA18CA045](https://openairdocs.org/ntsb/GAA18CA045), Nov 9, 2017: Cessna 172 (N2138W), Trenton, NJ, substantial damage. Probable cause: The pilot’s improper landing flare, which resulted in a bounced landing. 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.