Pengguna:NFarras/Proyek 3

Kontroversi

Tempat latihan yang berbahaya

Ahli Kelautan dan Perikanan dari Pemerintah Provinsi Bali, I Ketut Sudiarta, menjelaskan bahwa Laut Bali bagian utara merupakan "cekungan" yang memiliki kedalaman rata-rata 700-1300 meter dan dapat mencapai kedalaman hingga 1,000 meter atau lebih. Laut ini memiliki karakteristik curam dengan arus laut yang kuat dan turbulen. Terdapat pula patahan aktif yang memanjang hingga utara Pulau Flores.

Zeng Wei Jian, politisi Partai Gerindra, mendesak Kepala Staf Angkatan Laut untuk menjelaskan alasan dipilihnya Laut Bali bagian utara sebagai tempat latihan KRI Nanggala. Ia beranggapan bahwa wilayah tersebut termasuk sebagai "zona berbahaya" dan bukan tempat yang tepat untuk melakukan latihan. Zeng Wei Jian juga mengutip pernyataan Sudiarta yang menyatakan bahwa latihan kapal selam biasanya hanya dilakukan antara Situbondo, Jawa Timur hingga Singaraja, Bali.

Jumlah awak melebihi kapasitas

Zeng Wei Jian juga mempertanyakan alasan diizinkannya 53 orang untuk berada di dalam kapal selam. Ia mengutip pernyataan jurnalis pertahanan, Thomas Newdick, yang mengatakan bahwa berdasarkan buku "Combat Fleets of the World" edisi 1993, KRI Nanggala hanya memiliki kapasitas 34 awak. Kemungkinan kelebihan kapasitas juga sempat menjadi perhatian anggota Komisi I DPR, Mayjen (Purn.) TB Hasanuddin.

Death of three crew in a torpedo launch failure

TB Hasanuddin also said that three crew members of the Nanggala died in a failed torpedo launch exercise in 2012. The submarine was then sent to South Korea for repair.

Lack of oxygenation gel

Further Hasanuddin stated that oxygenation gel, used in the Nanggala to release additional oxygen gas, was not carried onboard the submarine when it sailed out to sea for the execise.

"I was informed that during diving, KRI Nanggala 402 was said not to carrying oxygen gel, but was still ordered to sail."

1,000m depth rating of Rigel's two underwater ROVs

The Nanggala was found at a depth of 838m, which was within the 1,000m depth rating of the underwater drones of the Rigel.

The Rigel operated two underwater drones:

a) Hugin-1000 Autonomous Underwater Vehicle (AUV) with a depth rating of 1,000m manufactured by Kongsberg Gruppen Norway, and

b) H-800 Hytec ROV, also rated to 1,000m deep, manufactured by French ECA Group.

Yudo Margono claimed that as the Nanggala was detected by Rigel sensors beyond 800m depth, the Rigel could not send its ROVs which he said has a depth rating of maximum 800m.

However that claim seemed to contradict the manufacturer specification of both the Hugin-1000 and the H-800, as both explicitly stated that their ROV model delivered to the Rigel and her sister ship the KRI Spica, have depth rating of 1,000m, well within the Nanggala's depth of 838m.

Kongsberg had also conducted a 3-weeks practical training for the Indonesian Navy to operate the Hugin-1000 AUV down to 1,000m deep offshore the island of Sumatra, Indonesia in 2015.

MV Swift Rescue - submarine search and rescue ship

After the Rigel claimed to have detected the Nanggala at 838m and was unable to send the ROVs, the location was passed over to the Singapore Navy's MV Swift Rescue.

MV Swift Rescue sent down its ROV Super Spartan AT 07:37am and successfully located the Nanggala at 09.04am and transmitted video recordings of the debris.

The launch of the ROV by MV Swift Rescue, at 07:37am on 24 April 2021, almost 8 hours after the Rigel had claimed to have located the Nanggala, also discounted the possibility of a confirmed finding of the Nanggala by the Rigel, since the dwindling oxygen supply inside the missing submarine was calculated to be exhausted by 03:00am on Saturday, 24 April 2021.

If the Nanggala had indeed been located, the ROV would have been launched immediately from the MV Swift Rescue to the sea floor to attach an oxygen hose before 03:00am.

"Hopefully before they can be found, the oxygen will be enough," Adm. Yudo Margono, the Indonesian Navy chief of staff, told a news conference.

Paradoxically, while the Indonesian military claimed that the Rigel's two ROVs were unable to reach the Nanggala as they were depth-rated at maximum 800m instead of 1,000m as stated by their manufacturers, the Singapore navy however claimed that MV Swift Rescue's ROV Super Spartan can search waters up to only "500m deep" when the Nanggala was located 838m deep, way beyond the Singapore's military claim maximum depth-rating of 500m for the Super Spartan, when the ROV took the close-up video recordings of the submarine on the sea floor.

Faulty underwater telephone

Defence magazine Janes reported that two sources within the Indonesian military that Nanggala’s multifrequency underwater telephone (UWT) system was defective throughout this operation, and that the boat has been relying on naval frequencies in the VHF and UHF bands for its communications needs while surfaced.

Invalid Optional Parameter, sister ship of KRI Nanggala (402)

PT PAL, an Indonesian state-owned shipyard that services submarines including the Nanggala.

“The lack of this UWT is preventing the boat from communicating with assets on the surface, and this is hampering our attempt to assess if an early intervention can be done to assist the distressed crew prior to a rescue attempt”, said one of the sources who spoke on the condition of anonymity. He also requested that further details of these systems be omitted so as not to compromise the confidentiality of equipment onboard Nanggala's sister boat Invalid Optional Parameter, which had been under service since 2018 at the state-owned shipyard PT PAL, which also serviced the Nanggala.

Commander's complaints of poor workmanships by PT PAL

Nanggala's commander, Let. Col Heri Oktavian, who died in the incident, had voiced his frustration about the maintenance status of the Nanggala to Edna C Pattisna, a close friend, who is also a reporter with local news media Kompas, with which she published under an article titled "Message from KRI Nanggala-402 Commander" in kompas.id website.

He stated that the workmanshop quality and maintenance services performed by state-owned shipyard PT PAL Indonesia were unsatisfactory and encountered frequent delays.

The Nanggala was last serviced by PT PAL last year in 2020.

He lamented that an officer encountered criticism from his superiors for reporting the poor workmanships by PT PAL on the Invalid Optional Parameter, a Changbogo-class submarine assembled by PT PAL's Surabaya yard and launched on 11 April 2019

"This submarine (the Alugoro) by PT PAL, there's nothing good about it," said Edna, quoting Heri Oktavian.

Edna said that Heri Oktavian hoped that the "decision makers carefully consider the TNI and its soldiers and not just "make the boss happy" ("Asal Bapak Senang") to attain promotions, positions or material gains."

Blackout

The commander of the Naval Staff and Command College Vice-Admiral Iwan Isnurwanto, who was a crewman of the Nanggala from 1990 to 2015, recalled that he was on board the Nanggala when it experienced a power failure.

On 27 April 2021 at a press conference at the naval headquarters at Cilangkap, East Jakarta, he explained the experience of total black-out while submerged. In 10 seconds, the submarine sank 90m, tail first at 45 degree, and the crew were ordered to moved forward to balance the ship. But since the submarine was at a steep angle, he had to crawl on his knees, said Iwan as he paused, emotionally-overcome by the incident.

Iwan said that the submarine chief engineer managed to execute an emergency main ballast tank blow and the Nanggala managed to surface. The power failure was due to a blown electrical fuse.