# NTSB NYC96IA022: Boeing 737-3B7, N373US, Portland, ME, November 2, 1995 - Type: NTSB incident investigation - Classification: Incident · No injuries · Incident investigation · Final report - Date: November 2, 1995, 18:28 local (23:28 UTC) - Place: Portland, ME - Location: 43.6456° N, 70.3086° W: Placed by OpenAirDocs at PORTLAND INTL JETPORT (PWM), within about a mile (OpenAirDocs) - Nearby events: https://openairdocs.org/map.md?lat=43.6456&lon=-70.3086&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 62 uninjured - Status: Completed, report March 21, 1996 - Report: Approved by Office Director - NTSB case key (mKey): 39100 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC96IA022 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/39100/pdf - Page: https://openairdocs.org/ntsb/NYC96IA022 ## Probable cause a bird strike during takeoff, which resulted in failure of several fan blades in the right engine and a partial loss of engine power. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with object, takeoff - initial climb - object - bird(s) (cause) - Loss of engine power(partial) - mech failure/malf, takeoff - initial climb - 1 engine - compressor assembly,forward fan - overload ## Analysis During rotation, on the takeoff roll, the right engine of a Boeing 737-3B7, ingested a bird. Several fan blades broke; however, there was no uncontained failure of the blades. There was no fire and the engine continued to run until shut down by the flight crew, after which the pilot returned for a single-engine landing. Feathers recovered from the engine belonged to a bird with a weight between 2.7 to 6.4 pounds, and a average weight of 3.8 pounds. The engine performed within the limits of its certification criteria. ## Factual narrative On November 2, 1995, at 1828 eastern standard time, a Boeing 737-3B7, N373US, operated by USAir as flight 1669, struck a bird in the number 2 engine, during takeoff from the Portland International Jetport, Portland, Maine. The occupants were not injured, and the airplane received minor damage. Instrument meteorological conditions prevailed, and the scheduled, domestic, passenger/cargo flight was operated on an Instrument Flight Rules (IFR) flight plan under 14 CFR 121. The CAPTAIN'S REPORT OF NON-STANDARD OR IRREGULAR OPERATION stated: At takeoff rotation we experienced an apparent bird strike in the #2 engine followed by a loud bang & excessive engine vibration. #2 engine was shut down, an emergency was declared & emergency procedures were followed ending with an uneventful single engine landing. According to the Powerplant Group Chairman Report, conducted by a Safety Board Investigator from RE-40, Aviation Engineering Services: ...The fuselage adjacent to the No. 2 engine did not have any apparent damage from engine debris. An inspection of the entire airplane did not show any indications of other bird impacts or damage...There were no penetrations through any of the engine casings...Feathers and other organic debris identified to be bird remains were found in the fan, compressor, and combustor. There was no indication of any preexisting engine damage...Feather pieces...[were identified] as a female Common Eider (Somateria mollissima). The weight of the female Common Eider can range from 42 to 103 ounces (2.7 to 6.4 pound) with the average weight being 61 ounces (3.8 pounds)...The airworthiness certification requirements for bird ingestion into a turbine engine...states, in part that the engine must demonstrate that the ingestion of a 4- pound bird may not cause the engine to catch fire, burst or release hazardous fragments through the engine case, generate loads greater than the engine mount attachment ultimate load limits, or lose the capability of being shut down...the fractured fan blades, and the gearbox mount pad adapter were returned to the NTSB Materials laboratory to determine the mod of fracture. Examination showed all the fractures were due to overstress, with no evidence of progressive cracking... ## Aircraft - Registration: [N373US](https://openairdocs.org/deregistered/N373US-2006-07-03), registration cancelled 2006-07-03, S/N 22952, built 1985 (OpenAirDocs) - Reported make and model: BOEING 737-3B7 - Registry model: [Boeing 737-3B7](https://openairdocs.org/model/boeing-737-3b7) (registry code 138447F) (OpenAirDocs) - Registry engine: [CFM International CFM56 series](https://openairdocs.org/engine/cfm-international-cfm56-series) (registry code 13802, turbo-fan) (OpenAirDocs) - Category: Airplane - Serial number: 22952 - Engines: CFM CFM56-3B2 22300 horsepower turbo fan - Damage: Minor damage - Flight: Part 121 - Registered owner: Usair - Airworthiness certificate: Standard, Transport - Departed: PWM - Destination: PHL, PHILADELPHIA, PA - Flight plan: IFR - Airport: PWM, Portland Int'L Jetport, runway 11, 6,800 × 150 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 43; airline transport; airplane ratings: multi-engine land, single-engine land, single-engine sea; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 13,140 total, 271 in this make and model ## Weather - Conditions: Instrument (IMC), Night/dark - Wind: 350° at 9 knots - Visibility: 1.75 statute miles - Lowest ceiling: 300 ft broken - Temperature: 50 °F, dew point 50 °F - Altimeter: 29.00 inHg - Observed at: PWM ## 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 19951102038739I](https://openairdocs.org/incident/19951102038739I), Nov 2, 1995: Boeing 7373B7, Portland, ME, Substantial damage. Loud bang right engine on takeoff. Vibration. Shutdown. Vectored low over ocean to clear runway. Injested ducks. ## Other investigations on N373US (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 MIA95IA214](https://openairdocs.org/ntsb/MIA95IA214), Aug 25, 1995: Boeing 737-3B7 (N373US), Fort Lauderdale, FL, incident, no damage. Probable cause: LOW ELECTRICAL RESISTANCE OF THE AUTOPILOT AILERON ACTUATOR FOR UNSPECIFIED REASONS WHICH RESULTED IN AN UNCOMMANDED ROLL TO THE RIGHT. 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.