Cathay Pacific pilots have had to deal with a series of in-flight incidents in recent months, two of them potentially hazardous. One has been widely reported but the other a month or so ago has not.
The report below is based on the website AeroInside and information supplied by aviation sources, active and retired. They did not want to be named.
In August a Cathay A330 flying from Taipei to Nagoya with 312 people on board was hit by hydraulic system problems. For safety the aircraft has three hydraulic systems, backing each other up. Two of them suffered loss of pressure with cockpit warnings alerting the pilots. The hydraulics operate the control systems: ailerons for banking, rudder for yawing and elevators for climbing and descending, among other equipment.
This happened 180nm southwest of Osaka. Just one hydraulic system was still operating normally. The Captain decided the safest course was to land the aircraft quickly and diverted to Osaka.
The pilots carried out a safe landing. Emergency services reported the aircraft was leaking hydraulic fluid, according to AeroInside.
A month earlier another serious incident occurred. Crew on a Cathay B777 flying from Hong Kong to Los Angeles reported smoke in the cabin. The aircraft was at 33,000ft 100nm south southwest of Shemya, a little-used USAF base on an island in the Aleutian chain. The female captain, apparently concerned the smoke could worsen, is reported to have warned the 294 people on board they might have to ditch. She banked the aircraft, headed straight for Shemya and landed 25 minutes later.
The airline said the cause of the smoke was a cooling fan near the cargo under the cabin floor.
In March this year another B777 enroute to London reported fire in the cabin. The Captain decided to divert to Amsterdam. On descent to the airfield the crew radioed that the galley fire had been extinguished.
Cathay Pacific operates 146 aircraft. Our aviation sources say this level of incidents is normal for such a large airline. The hydraulic system trouble described above was potentially serious. Another incident, which was pretty bad and could have been far worse, occurred four years ago.
Here is a summary of the Civil Aviation Department’s recent report: An A330 took off from Surabaya, Indonesia, after refueling there. The fuel was contaminated. Off Singapore, the pilots found they were having trouble with thrust control on both engines. They continued flying towards Hong Kong without taking the option of diverting to Singapore. The CAD report said both engines stalled about 45nm from Chek Lap Kok. With insufficient power to reach Hong Kong the pilots worked the engine flame-out checklist. This led to the left engine’s thrust increasing enough to get them to CLK.
About 45nm out of Hong Kong the right engine stalled. “This was now an emergency situation,” the CAD report said. “Flight crew workload had increased significantly.”
The crew radioed, “MAYDAY”. The report said this was appropriate. The left engine was performing strongly and it became clear to the crew that they would make CLK for an emergency landing. The captain flew a visual approach to the runway. On final descent he realised he could not reduce the thrust of the left engine. “The speed was not controllable,” the CAD said, going on to mention there was nothing the pilots could do other than continue the approach to landing.
The pilots deployed high-drag devices, speed-brakes and landing gear, to slow the aircraft.
Still, with the left engine’s power uncontrollable, they landed at about 231 knots, roughly 100 knots too fast. The Airbus bounced, slewed and the left engine’s cowling struck the runway.
The captain applied full braking force. The aircraft stopped about 300 metres from the end of the runway.
Five main-gear tyres deflated. Because of hot brakes, the captain ordered immediate evacuation. Fifty-seven people were hurt going down the slides, one seriously.
The CAD report praises the crew.