'Sawing sounds' on Tigerair flight alarm passengers

 An unusual "sawing sound" that persisted for about 30 minutes on board Tigerair's TR2105 caused some passengers to demand that they be allowed to disembark.

The noise was caused by a sensor fault that did not compromise safety, Tigerair later told Channel NewsAsia. The budget carrier also apologised for the inconvenience.

Upon boarding the Sep 3 flight from Bangkok to Singapore, one passenger, who identified himself as Mr C M Chan, said he was extremely worried by the "loud and continuous sound" that filled the plane as it taxied from the airway bridge. "I have been flying for years, and had never heard such a sound before," the 44-year-old consultant told Channel NewsAsia.

He said he asked a flight attendant to check with the pilot about the cause of the noise before take-off, and was then informed that it was due to the plane's hydraulic systems, but that the plane was safe to fly. Still concerned, Mr Chan said he asked to disembark, but the plane took off all the same.

Fellow passenger Ms Fong Weihui reported feeling strong vibrations from under the seats. "The sound from the faulty hydraulic pump roared loudly and the aircraft trembled violently as it was taking off," she said. She added that she found it "very shocking" when a flight attendant told her the plane had been experiencing this problem for three days.  

The pilot later made an announcement explaining the noise, but Mr Chan said he was not able to hear the message clearly. "I was really worried I would never land again. I only breathed a sigh of relief when I landed two hours later," he said. He added that a subsequent call to the airline's customer service department also did not yield any satisfactory answers.

Another passenger, Mr Faris Aziz, said he found the sounds “uncomfortable” and “irritating” and likened it to being in a "hell room, full of dogs' barking sounds". “I was so afraid that I almost had the feeling to get out of the plane if I could,” he recounted, but said the journey was otherwise a smooth one. He said he had heard similar sounds lasting just a few seconds on previous flights, and later found out through research that it is "pretty common on A320 planes".

A spokesman for the Singapore-based budget carrier Tigerair told Channel NewsAsia that the loud sound came from the aircraft’s Power Transfer Unit (PTU), which connects the aircraft’s hydraulic systems.

"The PTU is meant to be in operation only while the aircraft is on the ground. However, a sensor fault in the unit had caused it to continue running even after take-off," said the spokesman.

"At no time was the safety of the passengers and crew on board compromised, even though the sound might have caused disturbance. Nevertheless, we note that some passengers might have been troubled by the sound as the captain’s explanation over the PA system might have been partially masked by the noise. We apologise for any inconvenience caused, and would like to reiterate that safety is of utmost priority to Tigerair."

SOURCE