Journal of Accident Investigation

ALICE PARK AND CHRISTY SPANGLER
restriction resulting from incorrect rigging of the elevator
control system caused the aircraft’s loss of pitch control.
In the flight path animation, it was important to focus on the
airplane motion. Therefore, the environment was simplified,
showing only the runway and the hangar that was hit by the
airplane. Similarly, only that part of the flight path that was
significant to the probable cause was included. The time,
altitude, speed, and selected cockpit communications were
also shown to place the animation in perspective (figure 7).
Because the elevator control system is quite complex, only
certain components were needed to effectively communicate
the functions and adjustments pertinent to this accident
(figure 8). These animations of the cable mechanical system and
the properly and improperly adjusted elevator control system
effectively presented its correlation with the airplane’s loss of
pitch control during takeoff.
CONCLUSION
To determine and analyze the motion of an aircraft and the
physical forces that produce that motion, accident investigators
gather a variety of data that may not be easy to visualize. These
data define aircraft position and orientation through the flight
and are used to determine aircraft response to control inputs,
system failures, external disturbances, or other factors that could
affect its flight. Although figures and still images can be used to
replicate this physical evidence, a concise and simple but detailed
animation can greatly enhance investigators’ ability to visualize
and analyze the accident sequence of events. Animations
also enable investigators to simultaneously depict individual
data points in real time so that they can draw conclusions
and identify probable cause based on that data. Similarly,
animation can greatly simplify the explanation of those findings
THE AUTHORS
for a nontechnical audience, enabling them to understand the
probable cause and any associated safety recommendations. For
these reasons, the animations used to convey complex accident
investigation data must incorporate simplicity, elegance, and
scale of design. Engineers and animators work closely to
achieve this result by carefully crafting a storyboard that lays
out the data to tell a clear and coherent story. It is important to
emphasize that such animations are worthwhile only if they are
based on data that has been scrupulously measured, recorded,
and calculated to ensure accuracy of results.
REFERENCES
AmericAn Airlines flight 587. Accident
information: http://www.ntsb.gov/events/2001/AA 87/
default.htm
AmericAn Airlines flight 587. Presentation with
Static Graphs: http://www.ntsb.gov/events/2001/
AA 87/presentations/02_airplane_perf.pdf
AmericAn Airlines flight 587. Animations and
videos: http://www.ntsb.gov/events/2001/AA 87/
board_mtg_anim.htm
Air midwest flight 5481. Accident information:
http://www.ntsb.gov/events/2003/AM 481/default.htm
Air midwest flight 5481. Animations: http://www.
ntsb.gov/events/2003/AM 481/board_meeting_
presentations/presentations.htm
ALICE PARK is an Electrical Engineer/Radar Specialist in the Vehicle Performance Division at the NTSB. Ms. Park provides
technical analysis of FAA radar data in support of aircraft accident investigations and creates 3-D animations for use in public
Board Meetings to illustrate complex vehicle and occupant motions that occur during an accident sequence. She also codes and
debugs computer programs for processing radar data; performs 3-D computer simulations to reconstruct flight path of accident
aircraft; performs radar data studies; and represents the Safety Board in updating and coordinating with the FAA Technical
Center regarding the National Airspace System.
CHRISTY L. SPANGLER is an Audio/Visual Information Specialist in the Information Products Division at the NTSB. Ms.
Spangler’s projects have included the Charlotte takeoff accident 3-D animation, the Academy Virtual Tour, and other 3-D
animation, graphic design, intranet, and website projects. Her other experience includes her work as a media specialist for
the Biomedical Communications Department, Quillen College of Medicine, East Tennessee State University, in Johnson City,
Tennessee.
30 NTSB JOURNAL OF ACCIDENT INVESTIGATION, SPRING 2006; VOLUME 2, ISSUE 1
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