Aircraft Accident Brief Ntsb/aab-02/01 (Pb2002-910401): Egypt Air Flight 990, Boeing 767-366er, Su-Gap - National Transportation Safety Board Page 125
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160 The Egyptian Team attempted to have the bellcrank issue thoroughly investigated by the
NTSB Systems Group. Failing in this effort, the Egyptian Team took the unusual step of
preparing a safety recommendation letter from the Director General of the ECAA directly to the
FAA Administrator. The letter described the factual findings and the safety problems that had
been identified in the EgyptAir 990 accident investigation. The three recommendations, sent to
the FAA on June 4, 2000, stated:
1.
Require a cockpit indication in the Boeing 767 that would alert the flight crew to
abnormal PCA operation wherein a single fault in the elevator could result in
uncommanded elevator movement. Until such a cockpit indicator is installed,
require operators of Boeing 767 airplanes to perform daily -- rather than 400-hour
-- checks of the elevator system to identify faults in the elevator system;
2.
Review the Boeing 767 elevator control system design and conduct further
examination of the causes of the reported discrepancies found in the elevator
actuator bellcrank, and;
3.
In conjunction with Boeing, develop cockpit crew procedures to aid the flight
crew in identifying, isolating, and negating an uncommanded elevator hard-over
condition.
These safety issue recommendations prompted action by the FAA which requested that
Boeing undertake specific tests on the Boeing 767 elevator control system. The NTSB did not
participate in this testing even though the issues arose from the Flight 990 accident investigation
and appeared to be relevant to the accident. In any event, the identification and resolution of
these safety issues should have come through the NTSB to the FAA.
The tests initiated by the FAA resulted in dramatic safety findings. In a July 20, 2000,
Boeing message to all operators, Boeing stated that the test “ . . . results revealed that the
Elevator Power Control Actuator, Maintenance Planning Document Item Number 27-31-00-5B
test, which is required at a 400-hour interval, may not detect a failed hydraulic.” As a result, “. .
. the single system hydraulic test passed even though there was a sheared bellcrank in one
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