A332, vicinity Tripoli Libya, 2010
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On 12 May 2010, an Airbus A330-200 being operated by Libyan airline Afriqiyah Airways on a scheduled passenger flight from Johannesburg to Tripoli with a cruise relief First Officer on board and observing in the flight deck for the approach, commenced a go around in day Instrument Meteorological Conditions (IMC) after failing to obtain the required visual reference to land following a non precision approach to runway 09. However, soon afterwards, it crashed short of the intended landing runway just outside the aerodrome perimeter and was destroyed by the impact and subsequent fire with all but one of the 104 occupants being killed.
An Investigation was carried out by the Libyan Civil Aviation Authority. Flight Data Recorder (FDR) and Cockpit Voice Recorder (CVR) data was successfully downloaded from the recovered recorders. It was noted that both pilots and the observing relief First Officer had recorded exactly the same A330 flying hours total of 516 since qualifying on type at the manufacturer’s training facility the previous year and had all been previously rated on the Airbus A320.
The impact site was located 1200 metres from the threshold of the runway to which the approach had been made and 150 metres to the right of its extended centreline just outside the airport perimeter - see the diagram below taken from the Official Report. It was noted that the time of sunrise was ten minutes after the accident occurred, a time of day and year when fog and / or low Stratus cloud was not unusual, although not forecast on the day of the accident.
It was established that the First Officer had been PF and had flown a L/DME approach - see the chart below. Prior to commencement of this approach, the surface weather report had been given as ‘visibility 6km, sky clear’ and the applicable TAF was showing a ‘PROB 40’ of 5000 metres visibility in mist. Whilst the aircraft was on the approach and below 1200 ft Altimeter Pressure Settings, an aircraft which had just landed advised of fog patches beginning to form on the approach. As the aircraft passed 1000 feet QNH, the crew confirmed to ATC that they would report the runway in sight to obtain landing clearance.
With no response by the Captain to the automatic annunciation ‘MINMUM’ as the applicable MDA of 620 feet QNH (410 feet agl) was passed, the PF had then asked the Captain if the approach should be abandoned and followed this with a repeat of the automatic ‘THREE HUNDRED’ computer callout which had, by then, just occurred, the GPWS/TAWS “TOO LOW TERRAIN” alert activated and this appeared to have prompted the Captain to call a go around. This call was acknowledged and the go around initiated by the PF from 490 feet QNH (280 feet agl) with AP disconnection, TOGA selection, and landing gear retracted.
Although the go around was initiated promptly and positively by the PF, only four seconds later, he had begun to apply nose-down inputs on his side stick, resulting in a decrease in the pitch attitude of the aircraft until it became negative. The maximum altitude reached was only 670 feet QNH (450 feet agl). It was considered that these continued inputs had been “consistent with the high pitch attitude he could have perceived (and) typical of a somatogravic perceptual illusion occurring in the absence of outside visual references and (a failure to monitor) the artificial horizon”. It was noted that the PF “would have maintained nose-down inputs as long as he was feeling this effect, the pitch attitude perceived being relatively constant and greater than the theoretical pitch attitude during a go-around”. link to Appendix 6
It was surmised that the PFs successive callouts of ‘Flaps’ at this point may well have been “due to his detection of the red and black stripe on the speed tape and the very high speed trend due to acceleration”. It was further considered that this apparent ‘tunnel vision’ of the speed trend at the expense of the more central indication of the increasingly unfavourable aircraft attitude was indicative of a desire to avoid replicating what had happened during a go around from an unstable approach to the same runway with the same crew two weeks earlier during which the over speed warning had been was activated. This event had been identified by the Operator OFDM system but no follow up action had been taken by the time of the accident approach.
As the aircraft had begun to descend from 450 ft agl, it was noted that “neither crew member seemed to be aware of the flight path of the aircraft”. The Captain had responded to the PFs ‘Flaps’ calls and spoken to TWR but was not monitoring the flight path. As the aircraft descended again through the MDA equivalent 410 feet agl and the automatic ‘MINMIMUM’ Call activated again, there was no recorded response from either pilot.