# NTSB DFW08IA073: McDonnell Douglas MD-88, N935DL, Austin, TX, February 18, 2008 - Type: NTSB incident investigation - Classification: Incident · No injuries · Incident investigation · Final report - Date: February 18, 2008, 14:30 local (20:30 UTC) - Place: Austin, TX - Coordinates: 30.19, -97.668609 - Nearby events: https://openairdocs.org/map.md?lat=30.1900&lon=-97.6686&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470) - Highest injury: No injuries - Injuries: 148 uninjured - Status: Completed, report April 30, 2008 - Report: Approved by Office Director - Parties: San Antonio , Texas, Delta Airlines - NTSB case key (mKey): 67554 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DFW08IA073 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/67554/pdf - Page: https://openairdocs.org/ntsb/DFW08IA073 ## Probable cause The airplane struck a large bird while making a visual approach to the airport. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Object/animal/substance: animal(s)/bird(s)](https://openairdocs.org/ntsb-findings/03022045): Environmental issues › Physical environment · Not specified (probable cause); cases with it: [Mcdonnell Douglas MD-88, 1 case](https://openairdocs.org/ntsb-findings/03022045/cases.md?model=3023688), [All aircraft, 358 cases](https://openairdocs.org/ntsb-findings/03022045/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470) (defining event); cases with it: [Mcdonnell Douglas MD-88, 3 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=3023688), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis A commercial air carrier was on a visual approach to a FAR Part 139 airport when it struck a bird (Black Vulture) approximately 9 miles from the airport at an altitude of 1,800 feet above ground level. The impact resulted in airframe vibrations; however, both of the turbofan engine indications remained normal. The airplane landed uneventfully, and further examination revealed that the vulture struck the lower right hand corner of the radome. The impact resulted in damage to the glide slope antenna mount, the lower nose-web, and outer fuselage skin. In addition, the forward bulkhead (non-pressurized) fuselage rib was torn. Blood was also observed on the right engine's nacelle; however, an inspection of the first and second stage blades revealed no damage. A review of Federal Aviation Regulation (FAR) 139.337(a), titled Wildlife Hazard Management, revealed that a certificate holder is required to conduct an ecological study (Wildlife Hazard Assessment) if an air carrier aircraft experiences a multiple bird strike, an engine ingestion, or a damaging collision with wildlife other than birds. Part 139 also requires that an assessment be conducted if wildlife of a size or in numbers capable of causing one of these events is observed to have access to any airport flight pattern or movement area. According to a representative of the airport, they do not have an FAA approved Wildlife Management Plan since there had been no previous incidents that fit the criteria set aside by FAR 139.337(a) or Advisory Circular 150/5200-33B, titled Hazardous Wildlife Attractants on or Near Airports that required such a plan. ## Factual narrative On February 18, 2008, at 1430 central standard time, a McDonnell Douglas MD-88, N935DL, operating as Delta Air Lines flight 1877, sustained minor damage when it struck a large bird while on a visual approach to Runway 35R at Austin Bergstrom International Airport (AUS), Austin, Texas. None of the 5 crew members or 135 passengers were injured. A instrument flight rules flight plan was filed for the flight that departed Hartsfield-Jackson Atlanta International Airport (ATL), Atlanta, Georgia, at 1311, and was destined for Austin. Visual meteorological conditions prevailed for the schedule passenger flight conducted under 14 Code of Federal Regulations Part 121. The captain and first officer provided similar accounts of the incident. According to the captain's statements, the airplane was at an altitude of 1,800 feet above ground level (agl), approximately 4 to 5 miles from the airport, and at an airspeed of 210 knots, when he and the first officer saw two large birds in front of the airplane. Moments later one of the birds struck the bottom right side of the radome. The impact resulted in airframe vibrations; however, both engine indications remained normal. The first officer then declared an emergency and the captain informed the passengers about what had happened since it was "obvious we had collided with something." The airplane landed uneventfully, and once clear of the runway, the captain asked the airport's rescue and fire fighting (ARFF) personnel to assess the damage. They reported the impact area was "quite large with the bird imbedded into the radome." Federal Aviation Administration (FAA) safety inspectors performed an on-scene examination of the airplane. According to an inspector, the bird struck the lower right hand corner of the radome (as viewed from the cockpit). As a result, the glide slope antenna mount, the lower nose-web, and outer fuselage skin was damaged. In addition, the forward bulkhead (non-pressurized) fuselage rib was torn. Blood was also observed on the right engine's nacelle; however, an inspection of the first and second stage blades revealed no damage. Austin airport operations personnel sent photographs and feathers of the deceased bird to the Feather Identification Laboratory at the Smithsonian Institution, Museum of Natural History, who identified the bird as a Black Vulture. Airport operations personnel also produced several Airport Noise and Operations Monitoring System (ANOMS) plots, which showed that when the airplane was at a 1,800 agl, it was approximately 9 miles from the airport. A review of Federal Aviation Regulation (FAR) 139.337(a), titled Wildlife Hazard Management, revealed that a certificate holder is required to conduct an ecological study (Wildlife Hazard Assessment) if an air carrier aircraft experiences a multiple bird strike, an engine ingestion, or a damaging collision with wildlife other than birds. Part 139 also requires that an assessment be conducted if wildlife of a size or in numbers capable of causing one of these events is observed to have access to any airport flight pattern or movement area. According to a representative of Austin Airport, he said the airport "...does not have an FAA approved Wildlife Management Plan. To date there have been no incidents here at [AUS] that fits the criteria set aside by FAR 139.337(a) or [Advisory Circular 150/5200-33B, titled Hazardous Wildlife Attractants on or Near Airports] requiring such a plan." ## Aircraft - Registration: [N935DL](https://openairdocs.org/deregistered/N935DL-2020-11-09), registration cancelled 2020-11-09, S/N 49722, built 1989 (OpenAirDocs) - Reported make and model: McDonnell Douglas MD-88 - Registry model: [Mcdonnell Douglas MD-88](https://openairdocs.org/model/mcdonnell-douglas-md-88) (registry code 3023688) (OpenAirDocs) - Registry engine: [Pratt & Whitney JT8D series](https://openairdocs.org/engine/pratt-whitney-jt8d-series) (registry code 52053, turbo-jet) (OpenAirDocs) - Category: Airplane - Serial number: 49722 - Airframe hours: 51051 - Engines: Pratt & Whitney JT8D-219 21000 lbs thrust turbo fan - Damage: Minor damage - Flight: Part 121 - Registered owner: Delta Air Lines Inc - Airworthiness certificate: Standard, Transport - Last inspection: Continuous airworthiness, February 1, 2008 - Departed: ATL, Atlanta, GA - Destination: AUS, Austin, TX - Flight plan: IFR - Airport: AUS, Austin Bergstrom International, runway 35R, 9,000 × 150 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 47; injuries: none; airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review August 1, 2007; seat: left; flight hours: 10,586 total, 5,302 in this make and model - Co-pilot; age 53; injuries: none; airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review January 1, 2008; seat: right; flight hours: 5,453 total, 4,420 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 20° at 9 knots - Visibility: 10 statute miles - Lowest ceiling: 6,500 ft broken - Temperature: 61 °F, dew point 28 °F - Altimeter: 30.14 inHg - Observed at: AUS, 5 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). - [Incident 20080218011489I](https://openairdocs.org/incident/20080218011489I), Feb 18, 2008: Doug MD88, Austin, TX, Minor damage. (-23) On Monday, February 18, 2008 at approx 5:30PM, delta airlines flt #1877 (MD-88/N935DL/S#49733) struck an American black vulture at approx 2000' MSL. The… 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.