A Brussels Airlines Airbus A320-200 returned to Brussels Airport (BRU) after declaring a PAN PAN emergency en route to the Costa del Sol on August 7. The aircraft, a 17-year-old Airbus A320-200 performing flight SN-3735, was cruising at an altitude of 39,000 feet about 20 nautical miles west of Limoges, France, when the pilots noticed a problem with the hydraulics.
Rather than diverting to Limoges International Airport (LIG), Lyon or Bordeaux, the crew decided to return to the Belgium capital landing safely some 105 minutes after departure. According to the Aviation website The Aviation Herald, a replacement, Airbus A320-200, was brought in to transport the passengers to Spain. The holidaymakers arrived at Málaga-Costa del Sol Airport (AGP) after a delay of 3:45 hours.
The aircraft in which the hydraulic problem occurred, registration OO-SNM returned to service after being back in Brussels for 23 hours.
The A320 hydraulic system
While we do not know the cause of flight SN-3735s hydraulic system, we can tell you that it comprises three fully independent circuits labeled as Green, Yellow, and Blue.
The users are shared between the three circuits to ensure the aircraft’s control, even when one system is not working. On the Blue hydraulic system, the primary hydraulic pressure source is the electrical pump, with the auxiliary source being the Ram Air Turbine (RAT). The Constant Speed Motor/ Generator (CSM/G) is used to provide the necessary electrical power in emergencies. In the Green and Yellow circuits, the energy source is the Engine Driven Pump (EDP), with its backup being the Power Transfer Unit (PTU). The PTU automatically transfers hydraulic power between the Green and Yellow systems without fluid transfer when the pressure differential between the two circuits reaches 500 PSI.
An amber light is triggered if the fluid is low
If the fluid level in either the Green or Yellow circuit is low, an amber light is triggered on the Electronic centralized aircraft monitor (ECAM). Should the yellow light come on, pilots are requested to switch off the PTU and EDP to avoid overheating and losing a properly functioning hydraulic system. The triggering of the hydraulic amber caution light is prohibited on Airbus aircraft when flying below 1,500 not to pressurize the crew during critical moments of flight.
About Brussels Airlines
Brussels Airlines is part of the Lufthansa Group of airlines that include Austrian Airlines, Eurowings, Air Dolomiti, Swiss, Lufthansa CityLine, and German national flag carrier Lufthansa. Based at Brussels Airport, Brussels Airlines is the biggest airline in Belgium, flying to more than 100 destinations in Europe, North America, and Africa.
The Star Alliance member was created in 2006 following the collapse of SABENA and the merger of SN Brussels Airlines and Virgin Express. Particularly important to Brussels Airlines and the Lufthansa Group are its lucrative West African routes.
Currently according to Planespotters.net Brussels Airlines operates a fleet of 52 aircraft comprised of the following:
- 12 Airbus A319-100s
- 16 Airbus A320-200s
- 2 Airbus A330-200s
- 12 Airbus A330-300s
Have you ever flown on Brussels Airlines? If so, please tell us what you thought of them in the comments.