A Boeing 747-228F was scheduled to operate a flight from Brussels (EBBR, Belgium) to Campinas, Sao Paulo (SBKP, Brazil). With a scheduled stop at Dakar (GOOY, Senegal).
The damaged tail section with parts of the APU doors missing (Source & © AAIU Belgium)
The crew for the flight consisted of three pilots (a third pilot as a relief pilot), two engineers (an additional engineer for a routine check of the operating engineer) and a loadmaster. The co-pilot was to be the Pilot Flying (PF) for the first flight to Dakar. The commander delayed the departure for approximately 30 minutes, as the crew was only complete in the briefing room approximately 30 minutes before the scheduled departure time.
Once at the aircraft the co-pilot started programming the FMS (Flight Management System) for the flight while the commander checked the ATIS information. The relief pilot did the performance computation. During this computation, the Zero Fuel Weight (ZFW) (265.621 kg) was entered as the Take-off weight (363.721 kg). This error went unnoticed by the commander who checked the performance calculations.
Extract of the load sheet showing the actual ZFW, TOFW and taxi-weight (TW)
(Source & © AAIU Belgium)
The pre-flight preparations were completed, although interrupted on several occasions).
At one point the first officer noticed an error in the Take-Off performance, where the ZFW was noted as TOW. Subsequently, the Take-Off performance card was amended, but the take-off speeds were not corrected. After completing all pre-flight preparations the aircraft was pushed back and the engines were started. After receiving the taxi clearance the aircraft taxied to runway 25R.
After receiving the take-off clearance take-off was initiated at 14.59 lt (local time). The necessary call-outs were made as per standard procedures. When VR was called the PF pulled back on the stick however, rotation was not perceived as normal, and the controls felt sluggish, with the aircraft not climbing. The PF pulled back more on the control column, without noticeable results. At that time during the take-off the tail struck the runway, this was not heard by the crew as they were wearing their headsets.
The stick shaker was activated two times during the take-off roll. The commander ordered full thrust, followed by the flight engineer. The throttles were advanced up to the forward stop. At that point, the airplane had accelerated sufficiently to get airborne.
The damaged tail section with parts of the APU doors missing (Source & © AAIU Belgium)
The ATC noticed the tail strike. and alerted the departure controller as well as the fire brigade. Departures from runway 25R were interrupted awaiting an inspection of the runway.
The crew of the aircraft had in the meantime contacted the approach frequency who informed the crew of the tailstrike that had occurred during take-off. The crew was instructed to hold at ANT VOR, first at FL060, then later at FL080. The crew then reported they needed to dump fuel before returning to land in EBBR.
After about 1 hour and 20 minutes of flight, the aircraft landed on 25R, which had in the meantime been swept and brought back into operation. At 16:20 the aircraft landed at the touch-down aiming point and used the full runway length for deceleration. The fire brigade was in the meantime also deployed along the runway and followed the aircraft after landing. The airplane taxied on its own power to stand 906. After all traffic had vacated the runway, it was swept again. The tail section of the aircraft showed severe scraping damage. There were no injuries to the crew, the aircraft sustained substantial damage to the tail structure, with parts departing the aircraft.
Take-off sequence (Source & © AAIU Belgium)
An investigation was launched by the Belgium Federal Public Service Mobility and Transport, Air Accident Investigation Unit (AAIU Belgium). They conclude that the accident was caused by an inadequate take-off performance calculation, due to a wrong gross weight data input error in the software used for the computation of the take-off performance parameters and the failure to comply with the operator’s SOP for checking the validity of the data. Contributing factor(s) were determined to be. inadequate pairing of crew members with low experience and a lack of distraction management.
The full (and extensive) investigation report (which served as the source for this blog) can be accessed by clicking on the .pdf file below;
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