Bird Strike During Approach to Hamburg

Incident Overview and Flight Details On April 6, 2010, a Boeing 737-700 experienced a bird strike while on an Instrument Landing System (ILS) approach to runway 15 at Hamburg Airport. The aircraft, which had departed from Munich, was on a heading of approximately 297° at an altitude of about 2,150 feet and a calibrated airspeed of roughly 226 knots when the incident occurred around 09:43 local time. An unknown number of birds struck multiple parts of the aircraft, including the left front cockpit windshield. The impact caused the windshield to shatter and become smeared with blood, eliminating the captain's external view through that pane. The copilot continued the approach with the autopilot engaged, and the aircraft completed an automatic landing. After touchdown, the crew independently taxied the aircraft to its parking position on the apron. ## Personnel and Aircraft Information The responsible pilot was a 58-year-old captain holding an Airline Transport Pilot License (ATPL) under JAR-FCL German regulations. He was type-rated for the B737 300-900 series as a pilot-in-command and as a type-rating instructor (TRI). He held instrument flight rules (IFR) and Category III (CAT III) landing privileges, with a total flight experience of approximately 15,128 hours, including about 7,970 hours on the B737. His last simulator training was in March 2010, and his Class 1 medical certificate was valid until January 4, 2011. The second pilot was a 28-year-old copilot holding a Commercial Pilot License (CPL) under JAR-FCL German regulations. He was type-rated for the B737 300-900 series as a copilot and held IFR and CAT III landing privileges. His total flight experience was approximately 1,840 hours, including about 1,620 hours on the B737. His last simulator training was in October 2009, and his Class 1 medical certificate was valid until October 4, 2010. The aircraft was a Boeing 737-700, a low-wing, twin-engine jet with a tricycle landing gear configuration and 144 seats. Both engines were mounted under the wings and equipped with thrust reversers. The aircraft had a length of 33.60 meters, a wingspan of 35.79 meters, and a height of 12.50 meters. It was classified in Fire and Rescue Category 7 according to ICAO guidelines. The manufacturer was Boeing, with a model designation of B737-700, serial number 32,582, and a year of manufacture of 2001. The maximum takeoff weight was 70,068 kg, and the maximum landing weight was 65,317 kg. The airframe had a total flight time of 22,465:47 hours and 12,325 cycles. The engines were CFM56-7B22. The aircraft was certified for commercial operation in Germany on January 3, 2006, and had been operated by an airline since then. The Airworthiness Review Certificate was issued by the German Federal Aviation Office (LBA) on December 18, 2009, and was valid until December 21, 2010. ## Meteorological and Navigational Conditions Prior to the approach, the following routine weather report (METAR) was issued and available to the crew: issued at 09:20, wind from 170° at 7 knots, visibility 10 km or more, few clouds at 3,000 feet, broken clouds at 5,000 feet, temperature 8°C, dew point 4°C, QNH 1,026 hPa. The Instrument Landing System (ILS) for runway 15 was available and selected for the approach. The approach and landing were conducted using the autopilot. According to the crew, there were no restrictions for conducting the approach. ## Communications and Airport Information Radio communications were conducted in English with the relevant control authorities. The recordings of the radio communications were available for the investigation. Hamburg Airport is located at an elevation of 53 feet above sea level. It has two runways: 15/33 and 05/23. The asphalt runway 15/33 is 3,666 meters long and 45.80 meters wide, while the asphalt runway 05/23 is 3,250 meters long and 45.80 meters wide. The landing direction 15 is equipped with a Category I Instrument Landing System (ILS). Runway 15 was available for landing over its full length. The fire and rescue facilities met Category 9 standards. ## Flight Data and Aircraft Examination The aircraft was equipped with a Solid State Flight Data Recorder (SSFDR), P/N 9804700-042, manufactured by Honeywell. 971 parameters were available for the investigation. A Solid State Cockpit Voice Recorder (SSCVR), P/N 980-6022-001, manufactured by Allied Signal, was installed. The SSCVR had a recording capacity of two hours, and the entire recording duration was available for the investigation. The external examination revealed bird strike marks on the left and right sides of the nose section, as well as on each cockpit windshield. On the right engine, there were several larger blood stains (red) and in the area behind the fan, lower and upper right, nests of feathers (blue). Individual feathers were collected from these areas. Between the engine nacelle and the fuselage, there were multiple blood splatters on the underside of the wing, as well as in the area of the leading edge of the right horizontal stabilizer. On the left engine nacelle, the oil level check cover was open. Blood stains and tissue remnants were found both in front of the cover and inside the compartment behind the cover. The left horizontal stabilizer had a dent in the area of the leading edge. The left cockpit windshield was shattered but did not have a through-hole. The external view through this pane was no longer possible. The other left windshields were undamaged and clean. The right cockpit windshield was smeared with blood, but the external view was possible. The associated wiper was torn off. The other right windshields were undamaged. In the cockpit, large areas of glass fragments were found. No fire occurred. ## Research and Additional Information The feathers collected from the aircraft were sent to the German Committee for the Prevention of Bird Strikes in Air Traffic e.V. (DAVVL) for species identification. The investigation determined that the bird species was the Greylag Goose (Blässgans). These birds have a size of approximately 65–86 cm and a weight of approximately 1,700–3,100 g, corresponding to 3.75–6.83 lb. Excerpt from “Certification Specifications for Large Aeroplanes C-25”, Issue 4, November 2007, published by the European Aviation Safety Agency (EASA): “CS 25.631 Bird strike damage The aeroplane must be designed to assure capability of continued safe flight and landing of the aeroplane after impact with a 4 lb bird when the velocity of the aeroplane (relative to the bird along the aeroplane’s flight path) is equal to VC at sealevel or 0·85 VC at 2438 m (8000 ft), whichever is the more critical. …” “CS 25.775 Windshields and wipers … (b) Windshield panes directly in front of the pilots in the normal conduct of their duties, and the supporting structures for these panes, must withstand, without penetration, the bird impact conditions specified in CS 25.631. … (c) Unless it can be shown by analysis or tests that the probability of occurrence of a critical windshield fragmentation condition is of a low order, the aeroplane must have a means to minimise the danger to the pilots from flying windshield fragments due to bird impact. …” ## Investigation Team Lead Investigator: Andreas Bresky Contributors: Dieter Ritschel, Hans-Werner Hempelmann On-site Investigation: Axel Rokohl, Christian Blanke The investigation was conducted in accordance with the Act on the Investigation of Accidents and Incidents in the Operation of Civil Aircraft (Flugunfall-Untersuchungs-Gesetz - FlUUG) of August 26, 1998. The sole purpose of the investigation is the prevention of future accidents and incidents. The investigation does not serve to establish fault, liability, or claims.