Détails:The holiday charter flight landed at Larnaca (LCA) at 11:35 hrs after an uneventful flight from Manchester (MAN).
|Date:||lundi 26 mai 2003|
|Compagnie:||bmi British Midland|
|Numéro de série:|| 1045|
|Année de Fabrication:|| 1999|
|Moteurs:|| 2 IAE V2533-A5|
|Equipage:||victimes: 0 / à bord: 8|
|Passagers:||victimes: 0 / à bord: 213|
|Total:||victimes: 0 / à bord: 221 |
|Dégats de l'appareil:|| Substantiels|
|Lieu de l'accident:||70nm SE of Vienna, over Northeastern Hungary (Hongrie)
|Phase de vol:|| En vol (ENR)|
|Aéroport de départ:||Larnaca Airport (LCA/LCLK), Chypre|
|Aéroport de destination:||Manchester International Airport (MAN/EGCC), Royaume Uni|
|Numéro de vol:||8412|
The aircraft was refuelled to full tanks and, after a one hour 'turn-round', departed Cyprus for Manchester with the First Officer as the Pilot Flying. The commander's duties, as the Pilot Not Flying (PNF), were the management of the navigation and RT communications. The Standard Instrument Departure (SID) and climb to cruising altitude routed the aircraft to the west of the cloud building up on the north side of the island. The intensity and extent of this cloud was monitored by the crew on the weather radar. The aircraft was initially cleared to 8,000 feet but before reaching that altitude, a further clearance to a cruising level of FL340 was issued and the climb continued. The cabin crew were cleared to commence the cabin service and the aircraft levelled at FL340. The pilots had been monitoring Cb activity, on the weather radar, to the east of their track and approximately two hours into the flight they noted some isolated Cb activity ahead of the aircraft to the right and left of their track. The Cb activity to the right of track was minor and isolated. Cb activity to the left of track was less intense. The radar was set to a scale of 160 nm and with no significant returns ahead and no thunderstorm activity forecast the radar was switched OFF. The aircraft had been in clear skies above towering Cu for most of the flight and, in accordance with normal procedures, the radar had only been turned on when required.
As the flight progressed the aircraft entered some high Cirrus cloud. The FO, anticipating the possibility of turbulence, switched on the 'seat belt' signs and made a short public address (PA) informing the passengers and cabin crew that this was a precautionary measure. Shortly after the announcement the aircraft entered what the crew described as an area of 'light innocuous turbulence'.
Approximately 20 seconds later however, the turbulence increased through moderate to become severe. The autopilot (AP), which was selected ON in the 'Navigation Mode' at a speed of Mach 0.78 (M0.78), disconnected and the aircraft climbed rapidly above its assigned level. Intense hail then began to impact the aircraft. Both flight crew noted the master warning light illuminate as the autopilot disconnected but neither pilot heard the associated audio warning due to the noise of the hail. The FO flew the aircraft manually, selected engine ignition ON, set the speed to M.076 for the turbulence and turned on the cockpit dome light. The commander changed the range selector on Navigation Display (ND) to 40 nm to check for conflicting traffic on the Traffic Collision Avoidance System (TCAS), monitored the aircraft's speed on his Primary Flight Display (PFD), monitored the first officer's side stick inputs and cancelled the master caution light. Throughout, the PF attempted to regain FL340 and maintain track. The aircraft however, deviated 1,300 feet above to 300 feet below its assigned cruising level, rolling to angles of bank not exceeding 18 degrees. Indications on the Vertical Speed Indicator (VSI) confirmed that on at least one occasion the rates of climb or descent exceeded 5,900 feet per minute.
The commander of G-MIDJ transmitted to Budapest ATC informing them that they were unable to maintain FL340 due to severe turbulence. He was unable to hear the reply because of the hail. This also prevented the pilots from hearing each other for, although they were wearing headsets, it is normal practice for the intercom to be selected OFF and cross-cockpit conversation to be conducted without the use of intercom.
After the aircraft cleared the area of turbulence and hail associated with the storm cell the pilots noticed that the left front (commander's) windscreen and the right (first officer's) Direct Vision (DV) window had sustained severe hail damage. The commander felt his windscreen and noted that, although there were visible signs of damage to the outer layers and an increase in airflow noise, the inside layer was undamaged but the heating had failed. The only caption displayed on the Electronic Central Aircraft Monitoring (ECAM) system indicated that the aircraft's ILS status had been downgraded to Category (CAT) III single only. The commander therefore referred to the Quick Reference Handbook (QRH) for the procedure to deal with a 'cracked windshield'. This required a descent to FL230 or below and a maximum cabin differential pressure of 5 psi. Budapest ATC instructed the crew to contact Austrian Radar for their descent clearance and although only 'even' levels (FL240, FL220) are normally available for westbound flights on this route, the aircraft was cleared to the requested level of FL230. The aircraft descended gently at 1,500 feet per minute and, in accordance with the QRH procedure, the pressurisation was controlled manually. During the descent the Cabin Service Director (CSD) reported to the commander that everyone in the cabin was secure and that there were no injuries. The commander explained that the situation was still being assessed and an appropriate course of action considered.
The flight crew interrogated the system pages of the ECAM and noted that the engines appeared undamaged as individual engine vibration levels had not been affected as a result of the incident. The aircraft's fuel state had been checked approximately 20 minutes prior to the incident and at that time there had been an excess of 900 kg over the flight requirements. The aircraft appeared to have suffered only windscreen damage and the crew confirmed that at the lower cruising level of FL230 there was still sufficient fuel available to complete the flight. With sufficient fuel and no indication of the aircraft being unsafe the crew elected to continue to Manchester and informed ATC that they had damaged windscreens and would maintain FL230. Frequent monitoring of the fuel available against that required by the flight plan and the Flight Management Guidance System (FMGS) confirmed that sufficient fuel was available to land at Manchester with more than the minimum fuel required. When the crew contacted London ATCC they re-confirmed that the aircraft had damaged windscreens. They were radar vectored for a CAT I ILS approach to Runway 24R at Manchester where the PF was able to carry out a normal manual landing, having disconnected the AP at approximately 800 feet on finals. The commander was able to monitor the approach even though his windscreen was significantly crazed. The FO taxied the aircraft to the stand where, as was normal procedure for that stand, the commander was able to park the aircraft under the guidance of a marshaller. The passengers exited the aircraft normally using steps positioned at doors L2 and L4. It was not until the crew vacated the aircraft that they were aware of the extent and severity of the damage to other areas of the airframe. Even though the manufacturer later confirmed that the aircraft was in a safe condition to continue to its destination the commander stated that had he known the full extent of the damage he would have diverted after the incident to the nearest suitable airfield.
CONCLUSIONS: "This serious incident occurred when the aircraft, initially cruising in VMC, entered an area of cirrus cloud and penetrated an area of severe turbulence and hail. The weather radar, when used by the crew, did not show the severity of the weather ahead of the aircraft. This weather however, was observed by the crew of the B757 on their weather radar display. The apparent lack of significant weather returns resulted in the crew of the G-MIGJ turning off their weather radar. Having entered the area of turbulence and hail associated with a storm cell, the PF made measured control inputs, monitored by the commander, which reduced the excursions of the aircraft without imposing large load factors on the airframe or those onboard. The absence of injuries sustained by the passengers and crew was solely attributable to the timely illumination of the fasten seat belt signs and the fact that most passengers were seated with their seat belts secure. The actions by the cabin crew, in not attempting to move about the cabin but remaining on the floor during the worst of the turbulence, probably assisted in avoiding injury. The maintenance of communication between the flight deck and cabin crew throughout the flight meant that all crew were fully aware of the resulting course of action decided upon by the commander. Having made an assessment of the damage to the aircraft caused by the hail and the serviceability of the aircraft systems the flight deck crew continued to the planned destination of Manchester, monitoring the fuel situation to ensure adequate fuel was available to safely complete the flight.
It was not until the crew vacated the aircraft that they were aware of the extent and severity of the damage to other areas of the airframe. Even though the manufacturer later confirmed that the aircraft was in a safe condition to continue to its destination the commander stated that had he known the full extent of the damage he would have diverted after the incident to the nearest suitable airfield.
Official accident investigation report
|investigating agency: ||Air Accidents Investigation Branch (AAIB) - U.K. |
|report status: ||Final|
|report number: ||AAIB Bulletin 6/2004|
|duration of investigation:||372 days (1 year )|
|download report: ||
Airbus A321-231, G-MIDJ
(AAIB Bulletin 6/2004)
Ce plan montre l'aéroport de départ ainsi que la supposé destination du vol. La ligne fixe reliant les deux aéroports n'est pas le plan de vol exact.
La distance entre Larnaca Airport et Manchester International Airport est de 3446 km (2154 miles).