Journal of Accident Investigation

Investigative Techniques
Materials Examination of the Vertical Stabilizer from
American Airlines Flight 87
Matthew R. Fox and Carl R. Schultheisz, National Transportation Safety Board
James R. Reeder and Brian J. Jensen, NASA Langley Research Center
ABSTRACT
The first in-flight failure of a primary structural component made from composite material
on a commercial airplane led to the crash of American Airlines flight 87. As part of the
National Transportation Safety Board investigation of the accident, the composite materials
of the vertical stabilizer were tested, microstructure was analyzed, and fractured composite
lugs that attached the vertical stabilizer to the aircraft tail were examined. This paper
discusses the materials testing and analysis, the composite fractures, and resulting clues to
the failure events.
INTRODUCTION
On November 12, 2001, shortly after American Airlines flight 87 took off from Kennedy
International Airport, the composite vertical stabilizer and rudder separated from the
fuselage, rendering the airplane uncontrollable. The Airbus A300-600 airplane crashed into
a neighborhood in Belle Harbor, New York, killing all 260 persons aboard the airplane and
persons on the ground. This accident was unique in part because it was the first time
a primary structural component fabricated from composite materials failed in flight on a
commercial airplane.
As a result of its nearly 3-year-long investigation of the accident, the National Transportation
Safety Board determined that the probable cause of the accident was “the in-flight separation
of the vertical stabilizer as a result of the loads beyond ultimate design that were created
by the first officer’s unnecessary and excessive rudder pedal inputs. Contributing to these
rudder pedal inputs were characteristics of the Airbus A300-600 rudder system design and
elements of the American Airlines Advanced Aircraft Maneuvering Program.” 1
1 National Transportation Safety Board, In-Flight Separation of Vertical Stabilizer, American Airlines Flight 587,
Airbus Industrie A300-605R, Belle Harbor, New York, November 12, 2001, Aircraft Accident Report
NTSB/AAR-04/04 (NTSB Public Docket, 2004).
NTSB JOURNAL OF ACCIDENT INVESTIGATION, SPRING 2006; VOLUME 2, ISSUE 1 9