The submarine that sank off Bali could have been pushed into the depths by a so-called underwater wave. But experts also pursue other theories.
The Russian “Kursk”, the Argentine submarine “ARA San Juan” and now Indonesia’s “KRI Nanggala 402” – the horror that accompanies a submarine accident is so great that there is sometimes wild speculation about the background of tragedies. In order to find out what happened in the case of the Indonesian submarine and to pay their last respects to the 53 killed crew members, the government of the Southeast Asian country wants to have the sunken submarine salvaged, as it became known over the weekend. The submarine, which was broken in three parts, lies at a depth of over 800 meters on the seabed off the Indonesian island of Bali.
There are already several theories about the cause of the accident. In addition to a power failure, material fatigue and human error, according to some experts, it seems possible that an actually fascinating, natural phenomenon could have caused the disaster: a so-called internal wave that pulled the submarine into the depths.
A number of factors speak in favor of the theory of the force of nature, which is also known as underwater waves, as the Australian broadcaster ABC has found out. The station quotes Indonesian naval officials who report that such internal waves appear more frequently in the sea off Bali. These waves create intense vertical suction beneath the ocean surface. Such a suction could also have torn the submarine that sank off Bali into the depths.
According to the US space agency Nasa, these intense internal waves occur in the Lombok Strait – a strait between the islands of Bali and Lombok – about every 14 days. The underwater waves arise because a combination of strong tidal currents, an uneven seabed and water exchange between two channels – one shallower and one deeper – come together in the region.
A US study already showed in 2015 that such internal waves can create turbulence in the water more than 10,000 times more than waves on the sea surface. It is already known that they can slow ships down and shake submarines violently. But in the case of the Indonesian submarine, such a wave could now have killed 53 people.
In fact, Muhammad Ali, a former commander of the submarine who still works for the Indonesian Navy, said in a post by the submarine that the submarine actually sank in northern Bali at the same time as an internal wave occurred ABC quotes. He assumes that “natural reasons” caused the accident. His statements are supported by satellite images from the period, as other naval representatives emphasized to the press. Both the Japanese satellite “Himawari 8” and the European satellite “Sentinel” are said to have recorded internal waves in the region at the time.
But experts have also put forward other theories about what might have happened to the submarine. It was speculated that the submarine could have been hit by a missile from a foreign ship. A power failure could also have caused the accident. It is also discussed whether the submarine was overloaded. It was only designed for 34 people, but had 53 crew members on board, media reports said.
But those responsible deny this, according to ABC. The only 34 beds on board could be explained by the fact that the crew was divided into three shifts and slept alternately. Experts also believe that it is possible that material fatigue could have caused the accident. Cracks could have formed in the metal. The almost 60 meter long submarine “KRI Nanggala 402” was built in Germany in the late 1970s and was last overhauled in 2012.
The submarine lost contact with the outside world during an exercise in late April. At that time it was around 95 kilometers north of Bali. Several states, including the US and Australia, helped locate the missing crew. But despite the laborious rescue operation, none of the 53 seafarers could be rescued alive.
