Narrative:At 15:50 the engines of DC-8 ZK-NZB were started in preparation for a routine crew training flight within the Auckland terminal zone, which was scheduled to last two hours. The aircraft taxied to runway 23 for departure. At 15:59 the flight was cleared for takeoff when ready. The aircraft made an apparently normal takeoff roll. Rotation appeared more rapidly achieved and steeper than usual and the aircrafts tail passed unusually close to the runway surface. Almost immediately, the starboard wing dropped and the aircraft began turning to starboard while still in a nose-up attitude. The aircraft lost height by sideslipping inward and the starboard wing tip then struck a grassed area close to the edge of the runway. The aircraft pivoted about its nose at a fuselage-to-ground angle of about 50 degrees. Fire broke out in the vicinity of the starboard wing root and the aircraft rapidly began to disintegrate. Following nose impact, the entire flight deck section broke loose and eventually came to rest inverted.
Probable Cause:
PROBABLE CAUSE: "The incurrance of reverse thrust during simulated failure of no. 4 engine on takeoff. That condition arose when very rapid rearward movement of the power level generated an inertia force which caused the associated thrust brake lever to rise and enter the reverse idle detent. After lift-off, the minimum control speed essentially required to overcome the prevailing state of thrust imbalance was never attained and an uncontrollable roll, accompanied by some degree of yaw and sideslip in the same direction, ensued. When the condition of reverse thrust was recognised and eliminated, insufficient time and height were available to allow the aircraft to recover from its precarious attitude before it struck the ground."
Classification:
Simulated engine failure
Engine reverse issue
Loss of control
Sources:
» Aircraft Accident Report No. 1647 Douglas DC-8-52 : ZK-NZB Auckland International Airport 4 July 1966
» ICAO Aircraft Accident Digest No.16 - Volume II, Circular 82-AN/69 (68-72)
Follow-up / safety actions
DCA NZ issued 2 Safety Recommendations
Issued: -- | To: | ZK-NZB (1) |
That engine handling technique be revised to ensure that the
rate at which any power lever is moved back is insufficient to create
inertia to cause its associated thrust brake lever to rise toward or enter
on
the reverse idle detent; additionally, that the power lever always be
held in such a manner that rearward movement of the hand does not
impart a rotary motion to :the thrust brake lever.
(2) That some form of mechanical protection be incorporated in the
power lever and associated thrust brake lever system so that, should the
measures recommended in (1) above not be adhered to, incurrence of
unwanted reverse thrust wiIl be rendered impossible. |
Issued: -- | To: | ZK-NZB (2) |
That some form of mechanical protection be incorporated in the
power lever and associated thrust brake lever system so that, should the
measures recommended in (1) above not be adhered to, incurrence of
unwanted reverse thrust wiIl be rendered impossible. |
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Photos
Map
This map shows the airport of departure and the intended destination of the flight. The line between the airports does
not display the exact flight path.
Distance from Auckland International Airport to Auckland International Airport as the crow flies is 19960 km (12475 miles).
This information is not presented as the Flight Safety Foundation or the Aviation Safety Network’s opinion as to the cause of the accident. It is preliminary and is based on the facts as they are known at this time.