Composites and American Airlines Flight 587
On November 12, 2001, American Airlines flight 587 crashed into a residential neigborhood shortly after takeoff from Kennedy International Airport in New York. Within a day or two of the crash, the vertical tail of the Airbus A-300 was found nearly intact in nearby Jamaica Bay. The investigation began to focus on this composite structure, and what role if any the materials may have played in the crash.
The study of composites is a highly specialized discipline. Although aircraft manufacturers have been using these materials for many years, the National Transportation Safety Board (NTSB) does not have any composite experts on staff. The resources on this page provide both the novice and the expert with background information on composites as they relate to aircraft design and this crash in particular.
Glossary | ||
| Definitions of some of the more common technical terms appearing in the news. Check these pages over the next several days for expanded definitions and more detailed background information. | ||
| Composite: The A-300 tail is a laminated carbon fiber/epoxy matrix composite. It is also referred to as carbon composite, carbon plastic composite, and other similar variations. |
Delamination: The type of flaw most commonly cited in news articles. Delaminations are evident in the NTSB photos, but many of these would have formed when the tail broke off. |
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| Fatigue Failure: Most articles state that composites don't fatigue like aluminum. But what is a fatigue failure? |
Nondestructive Inspection: Tap tests, ultrasonic probing and other methods are used to detect flaws in composites without damaging the material. |
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NTSB Investigation |
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| Event Page: The main page from the NTSB related to this event. Contains basic facts about the crash, a list of primary team members, and a list of other parties involved in the investigation. General information about NTSB procedures is also available. |
Tail Photos: A collection of pictures from the NTSB showing the recovered tail and the attach points on the fuselage. Composite lugs on the tail attach to pinned joints on the fuselage. Failure occured at the composite lugs; the pin joints are intact. |
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New York Times Coverage | ||
| Articles from The New York Times that discuss the composite tail in detail. Free site registration is required. Articles more than seven days old are available on a fee basis. | ||
| November
15, 2001: Investigators begin to focus on the tail. This is the first major commercial crash involving composites. One of the tail fittings had been repaired for delaminations when the plane was originally delivered in 1988. |
November
16, 2001: Flight 587 encountered severe wake turbulence just before its breakup. The tail remained in place through that encounter and at least several seconds into the violent shaking of the plane. |
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| November
17, 2001: FAA orders inspections of other Airbus A-300 tails. Delaminations are suspected; visual signs might include cracked paint or surface distortions. Ultrasonic methods are available but not commonly used. |
November
19, 2001: If composites did contribute to the breakup of Flight 587, it could have implications for other planes such as the Boeing 777. At a minimum, new inspection requirements might be issued by the FAA. |
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