Filepix of KD Tunku Abdul Rahman, a Scorpene-class submarine.
PETALING JAYA: The Royal Malaysian Navy (RMN) is not using submarines in search-and-rescue (SAR) operations for the missing Malaysian Airlines MH370 flight as its sonar is not designed to conduct sea-bed searches.
"It is only good for detecting and searching for moving underwater contacts that produce sound, such as the sound of engines, movement, and radio or sonar transmissions," said RMN chief Laksamana Tan Sri Abdul Aziz Jaafar, in a statement issued Tuesday, in response to questions raised by certain quarters why RMN submarines had not been deployed.
He said submarines were not suitable for detecting contacts on the sea bed, adding that there were better options, including sonars fitted on hydrographic vessels, submarine rescue vessels, specialised rescue vessels and minehunters.
Among the ships participating in the search for MH370 is the Republic of Singapore Navy's submarine support and rescue vessel, MV Swift Rescue.
"Navies do not use a submarine for SAR missions for two other reasons; its limitation on optimum speed for sonar operation and the high risk of collision with other SAR vessels," he said.
Abdul Aziz said that when submarines are present, SAR ships would have to think about preventing mutual interference and waterspace management.
"It will surely complicate an already complicated situation. The rescue effort certainly can be better without these additional issues," added Abdul Aziz.
He said the use of a submarine to search for any black boxes is impractical.
"The black box transmits a very low frequency signal which must be located before it can be recovered.
"It can be localised by the use of a GPS intelligent buoy system as installed on submarine rescue vessels or any other specialised rescue vessel. Submarines are not fitted with the system," said Abdul Aziz.
Malaysia Airlines Flight MH370, on a B777-200 aircraft, departed Kuala Lumpur at 12.41am on March 8. It was expected to land in Beijing at 6.30am the same day.
Rescuers are still searching for the twin-engine plane that was carrying 239 people.