2nd UPDATE: Both Engines On Cathay Pacific Jet Malfunctioned

Both engines on the Cathay Pacific Airways Ltd. (0293.HK) jet that made an emergency landing in Hong Kong on Tuesday malfunctioned during the approach to the airport, according to Hong Kong's civil aviation department, in a rare incident that ended without serious injury to the hundreds on board.

After the pilots of the A330-300 plane shut off one malfunctioning engine, the aircraft's remaining engine suffered technical problems and wasn't producing the thrust needed to properly operate the plane, Director-General of Civil Aviation Norman Lo said Wednesday.

"The engine was stuck at a certain thrust level and the pilots weren't able to adjust it with their power settings," Lo said in an interview with Radio Television Hong Kong. The crew had trouble controlling the aircraft's speed, and as a result, the plane touched down at a much faster than normal speed for landing, he said.

"Based on the preliminary data we've seen, the emergency situation was very intense and the crew responded appropriately...there were just 20 minutes to react," said Lo, adding the cause of the incident is still under investigation.

In a news conference Wednesday, Cathay Pacific said at no time were both the aircraft's engines inoperative. As the plane made its approach into Hong Kong, one of its engines was reduced to "idle power" while the remaining one was stuck at 70% of maximum power, it said.

"This higher-than-normal power setting led to a higher-than-normal approach speed," said Dennis Hui, manager of maintenance and support at Cathay Pacific's engineering department. He said the aircraft touched down at around 230 knots, compared with the normal 135 knots.

As flight CX780 from Surabaya, Indonesia landed, a small fire broke out on its main landing gear as tires overheated when the pilots attempted to slow the plane using its brakes. The aircraft's 322 passengers and crew were evacuated via emergency slides, with eight passengers injured during the evacuation process.

While modern twin-engine jets are designed to function normally with only one engine operating, a malfunction in both engines is more problematic.

Paul Hayes, director of safety at London-based air transport consultancy Ascend, said the likelihood of two engines malfunctioning simultaneously is extremely rare. But he said, "if both engines did malfunction in some way, this suggests there is a common cause."

However, Hayes said it is far too early to speculate on the causes of the incident without further information about the flight, and urged the government to publish a preliminary report as soon as possible.

The Civil Aviation Department said Wednesday it had retrieved the aircraft's flight data recorders for analysis, and said it plans to invite Airbus, Rolls-Royce Group PLC (RR.LN), as well as French and U.K. air-crash investigators to join the investigation. The Airbus aircraft was manufactured in France, while its Trent 700 engines were made by Rolls-Royce in the U.K.

Airbus, a unit of European Aeronautic Defence & Space Co. NV (EAD.FR), and Rolls-Royce separately said that they would work closely with the airline and authorities to assist their investigations. A spokesman for the U.K.'s Air Accident Investigation Branch said it was sending two investigators to Hong Kong to help.

Cathay Pacific and its China-focused unit, Hong Kong Dragon Airlines Ltd., have nearly 50 A330-300s in service. The carrier said Wednesday it has no plans to ground the fleet.

This incident wasn't the first time Cathay Pacific has experienced a major problem with the A330 aircraft.

In 1997, Cathay Pacific and Dragonair grounded their entire A330 fleet for nearly two weeks because of problems with the planes' Rolls-Royce Trent 700 engines. Trouble with the gearboxes of the Rolls-Royce engines caused several in-flight engine shutdowns, prompting the carriers to take the planes out of service for modifications.

-By Jeffrey Ng, Dow Jones Newswires; 852-2802-7002; [e-mail]