Tuninter Flight 1153 was a scheduled flight from Bari-Palese Airport (BRI) in Italy to Djerba-Melita Airport (DJE) in Tunisia on August 6, 2005. The aircraft operating the flight on the given day was a 14 year old youngster. ATR 72–202 with the registration TS-LBB and the name Habib Bourguiba after a Tunisian lawyer and statesman.
The pilot of the aircraft was 45-year-old Captain Chafik Al Gharbi, a qualified and experienced pilot with a total of 7,182 flight hours, including 5,582 on the ATR-72. The flight’s first officer was Ali Kebaier Al-Aswad, 28, with 2,431 flight hours, including 2,130 on the ATR-72.
The road map. Image: GCmaps
Mechanics installed the wrong fuel gauge
The day before the flight, the aircraft underwent maintenance and had its fuel quantity indicator (FQI) replaced. Mechanics performing maintenance mistakenly installed an FQI designed for the ATR-42, a similar but smaller aircraft with smaller fuel tanks.
Ground crews refueling the aircraft rely on fuel readings to load the correct amount of fuel. The counters indicated that there were 3,050 kg of fuel on board the aircraft when there was only 790 kg of fuel. When fuel was added for the flight from Tunisia to Italy, 465 kg of fuel was added out of a total of 1,255, but counters showed the plane had 3,800 kg of fuel.
When the plane landed in Bari, it had less fuel than indicated
When the plane landed in Bari, there was only 305 kg of fuel in the tanks. Usually this would have triggered a low fuel warning light, but this is not the case because the fuel gauges indicated that the plane had 2,300 kg of fuel. As a result, only 256 kg of fuel was added for the return flight to Tunisia. When the flight took off from Bari, the fuel gauges indicated that the plane had 2,700 kg of fuel when in fact it only had 570 kg.
On Saturday August 6, 2005, while cruising over the Mediterranean Sea at 23,000 feet, the aircraft’s right engine failed. As the aircraft began to descend, the left engine failed at 21,900 feet. The captain and first officer had no idea they were out of fuel as the fuel gauges indicated that there was still fuel in the tanks.
Now desperate to restart the engines, the captain requested an emergency landing at Palermo Airport (PMO) on the Isle of Scilly. Without engines, the ATR-72 hovered for 16 minutes but was nowhere near the airport and sank in the sea 26 miles northeast of Palermo.
Despite breaking into three sections, the aircraft floated for some time. Search and rescue teams arrived approximately 46 minutes after the accident and began to retrieve survivors. Eight of the 39 passengers and crew died from the impact and eight others from drowning.
It was quickly determined that the plane had crashed due to fuel starvation in the engines. The cause of the starvation was the error of the mechanic to install fuel indicators designed for an ATR-42 and not for an ATR-72.
Investigators listed the following as contributing factors to the accident:
- Errors of mechanics when finding and fitting the fuel indicator.
- Errors made by the flight crew regarding operational procedures.
- Inadequate airline checks on crew compliance with operating procedures.
- Inaccuracy of information entered into the aircraft management and spare parts information system.
- Lack of a trained and responsible person to oversee the system.
- Maintenance and organization of the airline unsatisfactory.
- Lack of a quality assurance system.
- Insufficient supervision of the airline by a competent Tunisian authority.
- The installation features of the ATR-42 and ATR-72 allowed the wrong fuel indicator to be installed in the aircraft.
Following the accident, Italy banned Tuninter from flying in Italian airspace. In 2007, Tuninter renamed Sevenair and resumed flights between Italy and Tunisia. The airline changed its name again to Tunisair Express in 2011.