Aircraft Accident Brief Ntsb/aab-02/01 (Pb2002-910401): Egypt Air Flight 990, Boeing 767-366er, Su-Gap - National Transportation Safety Board Page 126
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160 system.” The Boeing document further advised that “a representative of the FAA witnessed the
sheared bellcrank test and advised that an Immediate (emergency) Adopt Airworthiness
Directive will be released concerning this issue. . . .” The Emergency Airworthiness Directive
was issued in August 2000.
As a result of the findings of this Emergency Airworthiness Directive which required the
prompt inspection of elevator bellcrank rivets, a second Airworthiness Directive was issued on
March 20, 2001 which imposed a more comprehensive and frequent inspection of elevator
components. This AD called for “. . . repetitive testing of the elevator control system to
determine if an elevator power control actuator (PCA) is rigged incorrectly due to yielded or
failed shear rivets in a bellcrank assembly for the elevator PCA, and follow-on actions, if
necessary. This action is necessary to prevent continued operation with yielded or failed shear
rivets in a bellcrank assembly for the elevator PCA, which could result in reduced controllability
of the airplane. This action is intended to address the identified unsafe condition.”
Finally, Boeing has announced that it is in the process of evaluating design changes to the
Boeing 767 elevator control system related to the bellcrank.
Clearly, a thorough and objective investigation by the NTSB would have identified this
safety issue. Instead, the issue was addressed only after the NTSB refused to do the requisite
analysis and after the Director General of the ECAA went directly to the FAA. Of primary
significance to the accident investigation is that the dual elevator PCA failure identified by the
Egyptian Team in January 2000 produces a flight profile very similar to that of the EgyptAir
Flight 990 accident.
Finally, the NTSB’s decision to include raw, unverified U.S. Federal Bureau of
Investigation (FBI) reports in the EgyptAir accident docket illustrated the NTSB’s preoccupation
with a deliberate act theory to the exclusion of a thorough consideration of the potential
mechanical deficiencies acknowledged by Boeing. The FBI had conducted an investigation of
the First Officer’s background and had concluded that there was no evidence of a criminal act –
no evidence of a deliberate act or a suicide – by the First Officer. The anonymous FBI reports
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