Bangalore Airbus Accident Report

Several aspects of the Bangalore crash are of particular interest because they have been suggested as contributing factors. Much has been said about the fact that Bangalore Airport is not ILS equipped, and it has been suggested that this could have caused problems. Indeed, the preliminary report of the investigating committee did criticise AeroFormation for not fully appreciating flight operation conditions in India and the lack of such installations when devising its training program. This claim is, however, refuted by Airbus and AeroFormation who stress that training programs are carefully designed to cater for a customer’s specific needs. In any case, on the day of the accident Bangalore weather conditions were very good. The A320 crew had been cleared to perform a visual approach into Runway 09, and there appears no apparent reason why the crew could not have done so safely. The lack of ILS equipment should not be a major concern to trained airline pilots, as the A320 flight crew were.

An important feature of the flight was that it was in fact a route check flight. The flight crew consisted of a Trainee Captain who flew the aircraft for most of the flight, and a Check Captain monitoring his progress. During the final thirty minutes of the flight, the aircraft was being flown by the Check Captain who was asking questions of the TraineeCaptain for educational and training purposes. It has been suggested in the media that the Check Captain had not even passed the AeroFormation A320 training program. AeroFormation have refuted this claim, showing that the captain did pass the standard A320 course and therefore was well able to fly the aircraft. He was an experienced airline pilot with some 10,000 hours airline flying time, mainly on turboprop and 737 aircraft; some 68 hours had been flown on the A320. Similarly, the Training Captain also was an experienced airline pilot with a similar number of flight hours, needing only to be checked out on the A320. The Check Captain, however, was not authorised as such by Airbus/AeroFormation – he was one of at least five such Indian Airlines Check Captains in this situation. Despite this, the fact remains that the aircraft was flown by an experienced pilot who, for reasons not known, was able to crash the A320 in relatively fine conditions.

Full details of the flight were not available from Airbus, either because they had not yet been released by the Indian investigating committee, or for legal reasons could not be announced before the final report is released. From what information is readily available, however, Airbus have been able to assert that the crash was solely the result of pilot error. It is known, for instance, that the crew was definitely not landing the aircraft as the Airbus manual specifies. The landing approach was being made in Open Descent Idle Mode (ODIM), this being in direct contravention of the Airbus lndustrie A320 aircraft flight manual. In ODIM, the autothrottle was fixed to full idle so the aircraft was not being properly controlled for landing. The aircraft was losing speed so could only lose height at a rapid rate. The situation was exacerbated by the lowering of undercarriage and the flaps to stage 3 position for approach. The aircraft could in effect only go down, its angle of attack controlled by the A320’s computer.

The Check Captain thus failed during the engine idle approach to monitor the safety of the aircraft’s approach as required by the Flight Crew Operating Manual. Neither crew member monitored the aircraft’s speed, nor properly its height. There is definitely no possibility that thecrew were ‘frazzled’ by the A320’s fly-by-wire technology so that they did not realise they were in Open Descent Idle Mode. Airbus point out that at one stage the Check Captain acknowledged that the aircraft was in ODIM (confirmed on the yet to be released Cockpit Voice Recorder tape), while later the Training Captain even suggested that vertical speed be used for the approach, this being the standard method of approach according to the Operating Manual. For some unknown reason the pilot appears simply to have continued his approach regardless of what he had been taught.

The aircraft was descending rapidly and it should by this stage have been obvious that it would not reach the runway. At about 500ft the aircraft’s speed went below the standard recommended approach speed and continuously decreased down to 25kts below the nominal approach speed. This situation lasted for about 30 seconds. Cockpit warnings were apparently ignored by both flight crew and a recovery procedure was not applied. Only at about 140ft, with the aircraft at minimum speed/ maximum angle of attack and with a very high flight path angle, is it obvious that the crew fully realised their situation when the captain stated “Hey! We are going down. ” Crew reaction was to push the throttles full forward, though the Alpha Floor activation (automatic go around) had already occurred 3-4 seconds earlier. Acceleration of both engines, as initiated by the Alpha Floor, was actually slightly better than the certified values.

Both crew members instinctively pulled their sidesticks to full nose up elevator order. Airbus point out that in any other aircraft type this action would have stalled the aircraft, the consequence being that there would have been no crash survivors. Only the electronic flight control system maintained the maximum angle of attack and prevented a stall. However, at this late stage of crew reaction there was no chance of the crash being avoided.

The above crash details have been revealed to Airbus primarily from the CVR transcript. Obviously without all details of the flight Airbus are unable to fully ascertain the cause of the accident. It is expected, however, that the findings of the Indian investigating committee will reach a similar conclusion – that the Bangalore crash was the result of pilot error. Airbus do not believe that blame should be directed at their organisation. The A320 has proven to be a safe and reliable aircraft (the only other crash – Habsheim on 26th June 1988 – was the result of human error in similar circumstances where the aircraft was flown well beyond its flight envelope) and the AeroFormation training program has not in the past proven to be deficient in operation with more than a thousand pilots being trained for both Airbus and ATR aircraft.