Operation Trikora

Operation Trikora was an Indonesian military combined operation which aimed to seize and annex the Dutch overseas territory of Netherlands New Guinea in 1961 and 1962. After negotiations, the Netherlands signed the New York Agreement with Indonesia on 15 August 1962 to hand over Western New Guinea to the United Nations.

Operation Trikora
Part of the West New Guinea dispute and Cold War
Yos Sudarso Postage Stamp.jpg
Indonesian stamp commemorating the Battle of Arafura Sea
Date19 December 1961 – 15 August 1962 (1961-12-19 – 1962-08-15)
Result Indonesian political victory
Western New Guinea ceded to the United Nations then to Indonesia
 Soviet Union
(air & naval support)


Commanders and leaders
Indonesia Suharto
Indonesia Abdul Haris Nasution
Indonesia Ahmad Yani
Indonesia Omar Dhani
(from January 1962)
Indonesia Eddy Martadinata
Indonesia Leonardus Benjamin Moerdani
Indonesia Leo Wattimena
Indonesia Soerjadi Soerjadarma
(until January 1962)
Indonesia Sri Mulyono Herlambang
Indonesia Boediarjo
Soviet Union Commandor Gennadi Melkov
Soviet Union Commandor Rudolf Ryzhikov
Netherlands C.J van Westenbrugge
Morning Star flag.svg W.A. van Heuven
13,000 soldiers
7,000 paratroops
4,500 marines
139 aircraft
 Soviet Union:
3,000 soldiers
6 submarines
3 Tu-95 strategic bombers

10,000 soldiers
1,400 marines
1000 volunteers
5 destroyers
2 frigates
3 submarines
1 Aircraft Carrier
Casualties and losses
400 killed (approximately)
200 wounded
55+ captured
1 motor torpedo boat sunk
2 motor torpedo boats damaged
100 killed [1]


When the rest of the Dutch East Indies became fully independent as Indonesia in December 1949, the Dutch retained sovereignty over the western part of the island of New Guinea and took steps to prepare it for independence as a separate country. The Dutch and West Papuan leaders argued that the territory did not belong to Indonesia because the West Papuans were ethnically and geographically different from Indonesians; had always been administrated separately; and that the West Papuans did not want to be under Indonesian control.[2] After its independence until 1961, Indonesia attempted to gain control of Western New Guinea through the United Nations without success. Since the Indonesian National Revolution, Indonesian nationalists had always regarded Western New Guinea as an intrinsic part of the Indonesian state.[3] They also contended that Western New Guinea (Irian Barat) belonged to Indonesia and was being illegally occupied by the Dutch.[4][5]

Since 1954, Indonesia had been launching military raids into Western New Guinea. Following the failure of negotiations at the United Nations, the president of Indonesia, Sukarno, escalated pressure on the Netherlands by nationalising Dutch-owned businesses and estates and repatriating Dutch nationals. These tensions between Indonesia and the Netherlands led to a sharp reduction in trade between the two countries. Following a sustained period of harassment against Dutch diplomats in Indonesia, Indonesia formally severed ties with the Netherlands in August 1960. Indonesia also increased its military pressure on Dutch New Guinea by purchasing weapons from the Soviet Union and the Eastern Bloc. Over the following years, the Sukarno government would become dependent on Soviet military support.[6]

On 19 December 1961, Sukarno decreed the establishment of the People's Triple Command or Tri Komando Rakyat (Trikora) in order to annex what Indonesia called West Irian by 1 January 1963. Trikora's operational command was to be called the Mandala Command for the Liberation of West Irian (Komando Mandala Pembebasan Irian Barat) with Major-General Suharto (the future President of Indonesia) serving as its commander. In preparation for the planned invasion, the Mandala command began making land, air, and sea incursions into West Irian.[4][7] As a result, Indonesia embarked on a policy of confrontation against the Dutch over control of Western New Guinea.[6] Sukarno also embarked on a policy of "progressive mobilization" to prepare the nation to carry out his commands.[8]

While the United States, the United Kingdom and Australia sided with the Netherlands' claims to Western New Guinea and were opposed to Indonesian expansionism, they were unwilling to commit military support to the Dutch. The Netherlands was unable to find sufficient international support for its New Guinea policy. By contrast, Sukarno was able to muster the support of the Soviet Union and its Warsaw Pact allies, and the Non-Aligned Movement. In response to Indonesian claims, the Netherlands was forced to speed up the process of preparing the West Papuans for self-rule from 1959. These measures included the establishment of a legislative New Guinea Council in 1960; establishing hospitals, a shipyard in Manokwari, agricultural research sites and plantations; and the creation of the Papuan Volunteer Corps to defend the territory.[9][10]



Indonesia began to seek weapons from abroad in the face of the conflict between Indonesia and the Netherlands. Indonesia tried to ask for help from the United States, but failed. Finally, in December 1960, General A. H. Nasution went to Moscow, Soviet Union, and finally succeeded in entering into an arms trading agreement with the Soviet Union government worth 2.5 billion US dollars on long-term payment terms. After this purchase, the TNI claimed that Indonesia had the strongest air force in the southern hemisphere.

United States did not support the surrender of West Irian to Indonesia because the Bureau of European Affairs in Washington, DC considered this to "replace white occupation with brown occupation." But in April 1961, Robert Komer and McGeorge Bundy began to prepare plans for the United Nations to give the impression that surrender to Indonesia was legal. Although in doubt, the president John F. Kennedy finally supported this because of the climate of the Cold War at that time and fears that Indonesia would ask for help from the Soviet communists if it did not have US support. Indonesia bought various kinds of military equipment, including 41 Helicopters MI-4 (light transport), 9 Helicopters MI-6 (heavy transport), 30 jet plane MiG-15, 49 ambush aircraft MiG-17, 10 ambush aircraft. MiG-19, 20 supersonic MiG-21, 12 submarines class submarine|Whiskey, dozens of corvettes, and 1 Sverdlov class cruiser (named according to the target area of operation, namely KRI Irian). Of the types of bombers, there were 22 light Ilyushin Il-28 bombers, 14 long-range bombers TU-16, and 12 maritime versions of TU-16 aircraft equipped with weaponry anti-ship missile (missile) air to surface type AS-1 Kennel. While of the types of transport aircraft there were 26 light transport aircraft types IL-14 and AQvia-14, 6 heavy transport aircraft types Antonov An-12 B made Soviet Union and 10 heavy duty transport aircraft C-130 Hercules made in the United States.[11]


To achieve air superiority, the first preparations undertaken by the AURI were to repair war-damaged airbases, which would be used for infiltration operations or face open operations on the West Irian mainland. Air Base and Landing Strip which are widely available along the borders of Maluku and West Irian, are relics of Japan. The airbase and landing strip were last used in 1945, and after that they were no longer used. The situation of the Air Base and Landing Strip was not maintained and many were damaged and overgrown with weeds and trees.

Soviet involvementEdit

The support of the Soviet Union to Indonesia played a crucial role in ending the conflict over New Guinea; thanks to the support of Russian submarines and bombers, Indonesia dared to risk an attack on Dutch troops. And due to the Russian presence, the United States put pressure on the Netherlands. At the height of the Cold War, just before the Cuban crisis, America wanted to prevent at all costs that strategically important Indonesia would end up in the communist sphere of influence. By enforcing the transfer of New Guinea, the United States could keep the regime of Sukarno friendly. Eventually, The Hague gave way to American pressure and the threat of an attack on New Guinea. The Russian support was secret - the Soviet 'volunteers' wore Indonesian uniforms - but to the dismay of the Russians, the Indonesian Foreign Minister Soebandrio let the Russian willingness to actively provide military support leak to the American ambassador in Jakarta, according to Khrushchev’s memoirs.[12] [13] Admiral Sudomo revealed in a newspaper article in 2005 that 6 six Russian submarines supported the amphibious operations. The Russian submarines were waiting in Bitang, East Sulawesi. The Russian submarine S-235 had the task to attack the Dutch fleet in Manokwari.[14] Submarine commandor Rudolf Ryzhikov recalled in an Russian article he received orders on 29 july from Admiral Sergey Gorshkov to patrol a combat zone West of New Guinea and sink any shipping after midnight 5 August.[15] [16] [17] Naval officer and Historian Matthijs Ooms has shown in his masterpaper that the Dutch naval intelligence service, MARID (Marine Inlichtingendienst), received information in the summer of 1962 that Soviet crews were manning Indonesian submarines and Toepolev bombers.[18][19] In his memoirs, Nikita Khrushchev freely admitted that during the West New Guinea crisis Soviet personnel had been commanding Indonesian submarines and piloting Tu-16s.


Indonesia approaches countries like India, Pakistan, Australia, New Zealand, Thailand, United Kingdom, Germany, and France so that they would not give support to the Netherlands if war broke out between Indonesia and the Netherlands. In the United Nations General Assembly in 1961, the UN Secretary General U Thant asked Ellsworth Bunker, a diplomat from the United States, to submit proposals on solving the problem of the status of West Irian. Bunker proposed that the Netherlands submit West Irian to Indonesia through the United Nations within a period of 2 years.


On December 27, 1958, President Soekarno issued Law No. 86 of 1958 concerning the nationalization of all Dutch companies in Indonesia. Nationalized companies such as:

  1. Plantation company
  2. Nederlandsche Handel-Maatschappij
  3. Electricity company
  4. Petroleum companies
  5. Hospital (CBZ) becomes RSCM

And other policies such as:

  1. Moving the Indonesian tobacco auction market to Bremen (West Germany)
  2. Dutch workers strike in Indonesia
  3. Prohibit KLM (a Dutch airline) from crossing Indonesian territory
  4. Prohibit the screening of films - Dutch films

Total ConfrontationEdit

In accordance with the development of the Trikora situation, it was made clear by the instructions of the Commander in Chief of the Highest Commodity of Liberation of West Irian No. 1 to the Commander of the Mandala, the contents of which were as follows:

  • Plan, prepare and conduct military operations with the aim of returning the territory of West Irian to the Republic of Indonesia.
  • Developing the situation in the Province of West Irian in accordance with the struggle in the field of diplomacy and in the shortest possible time in the West Irian Region can be de facto created free areas or there is an element of power / regional government of the Republic of Indonesia.

  Strategies developed by the Commander of Mandala to carry out these instructions.

  • Infiltration (infiltration) (until the end 1962), namely by entering 10 companies around certain targets to create a strong de facto free area that is difficult to be destroyed by the enemy and develop territorial control by bringing the people of West Irian together. .
  • Exploitation Stage (early 1963), namely carrying out an open attack on the enemy military host and occupying all important enemy defense posts.
  • Consolidation Phase (early 1964), namely by demonstrating power and establishing the absolute sovereignty of the Republic of Indonesia throughout West Irian.

  Implementation Indonesia carried out the infiltation stage, then carried out the Jayawijaya operation, but before it was carried out on 18 August 1962 there was an order from the president to stop the firing.

Indonesian military operationsEdit

The disputed territory of West New Guinea

In 1962, Indonesian incursions into the territory in the form of paratroop drops and the naval landings of guerrillas were used to step up Indonesian Foreign Minister Subandrio's diplomatic confrontation with the Dutch.[10] Operation Trikora was to unfold in three phases: infiltration, exploitation and consolidation, all under cover of the Indonesian Air Force. The plan called first for the insertion of small bands of Indonesian troops by sea and by airdrop, who would then draw Dutch forces away from areas where the exploitation phase would stage full-scale amphibious landings and paratroop operations to seize key locations. The consolidation phase would then expand Indonesian control over the whole of Western New Guinea.[4]

On 15 January 1962, the infiltration phase of Operation Trikora began when four Indonesian Navy motor torpedo boats attempted to land a unit of 150 marines on the south coast of New Guinea near Vlakke Hoek. The force was detected by a Dutch Lockheed P2V-7B Neptune aircraft and the Indonesian boats were intercepted by three Dutch destroyers. During the subsequent Battle of Arafura Sea, one Indonesian boat was sunk and two others were badly damaged and forced to retreat. Thus, this planned Indonesian amphibious landing ended disastrously with many crew members and marines being killed, among them Commodore Yos Sudarso, the Deputy Chief of the Indonesian Navy Staff. Some 55 survivors were captured. Over the next eight months, the Indonesian forces managed to insert 562 troops by sea and 1,154 by air drops. The inserted Indonesian troops conducted guerrilla operations throughout Western New Guinea from April 1962 onwards, but they were largely militarily ineffective. At least 94 Indonesian soldiers were killed and 73 were wounded during the hostilities. By contrast, the Dutch suffered only minimal casualties.[4][5]

Indonesian military activity continued to increase in the area through mid-1962 in preparation for the second phase of the operation. The Indonesian Air Force began to fly missions in the area from bases on surrounding islands, with Soviet-supplied Tupolev Tu-16 bombers armed with KS-1 Komet anti-ship missiles deployed in anticipation of an attack against the HNLMS Karel Doorman.[4][5]

By the summer of 1962, the Indonesian military had begun planning a large-scale amphibious and air assault against Biak, the Netherlands' main power base in West Irian. This operation would have been known as Operation Jayawijaya ("Victory over Imperialism") and would have included a substantial task force of 60 ships including several which had been supplied by Sukarno's Soviet and Eastern Bloc allies.[5][7] On 13 and 14 August 1962, air drops of Indonesian troops were staged from Sorong in the northwest to Merauke in the southeast as a diversion for an amphibious assault against the Dutch military base at Biak Island by a force of 7,000 Army (RPKAD) and Air Force (PASGAT) paratroopers, 4,500 marines and 13,000 army servicemen, from various military districts (KODAMs). However, the Dutch Navy's Marid 6 Netherlands New Guinea (Marid 6 NNG) signals intelligence section and Neptune aircraft detected the invasion force and alerted their command.[4][5]

According to Wies Platje, the Royal Netherlands Navy was responsible for the defence of Western New Guinea. In 1962, the Dutch naval presence in New Guinea consisted of five anti-submarine destroyers, two frigates, three submarines, one survey vessel, one supply ship and two oil tankers. Dutch air power in Western New Guinea consisted of eleven Lockheed P2V-7B Neptune aircraft from the Royal Netherlands Navy[20] plus 24 Hawker Hunter jet fighters from the Royal Netherlands Air Force. In addition, Dutch ground forces consisted of several anti-aircraft artillery units, five Royal Netherlands Marine Corps companies and three Royal Netherlands Army infantry battalions. As part of the planned defence, the Dutch had considered using Marid 6 NNG to disrupt the Indonesian military's communication systems.[5]


The Sukarno-era "West Irian Liberation Statue" in Jakarta

On 15 August 1962, the Netherlands recognized Indonesia's resolve to take Western New Guinea. Since it was unwilling to be drawn into a protracted conflict on the other side of the world, the Dutch government signed the New York Agreement, which handed the colony to an interim United Nations administration. Consequently, Operation Jayawijaya was called off and Western New Guinea was officially annexed by Indonesia in 1963. The Dutch decision to hand over Western New Guinea to Indonesia had been influenced by its main ally, the United States. While the Netherlands was a member of the North Atlantic Treaty Organization and thus an ally of the Americans, the Kennedy Administration was unwilling to antagonize Indonesia since it was trying to court President Sukarno away from the Soviet orbit.[5] The Indonesian military's incursions into West Irian, plus the substantial Soviet military assistance to the Indonesian military, had convinced the United States government to pressure the Dutch to seek a peaceful solution to the conflict.[21]

The New York Agreement was the result of negotiations that were spearheaded by the American diplomat Ellsworth Bunker. As a face-saving measure for the Dutch, Bunker arranged for a Dutch-Indonesian ceasefire which would be followed by the handover of Western New Guinea on 1 October to a temporary United Nations Temporary Executive Authority (UNTEA). On 1 May 1963, Indonesia formally annexed Western New Guinea. As part of the New York Agreement, it was stipulated that a popular plebiscite, called the Act of Free Choice, would be held in 1969 to determine whether the West Papuans would choose to remain in Indonesia or seek self-determination.[22] However, American efforts to win over Sukarno proved futile and Indonesia turned its attention to the former British colony of Malaysia, resulting in the Indonesian-Malaysian Confrontation. Ultimately, President Sukarno was overthrown during the Indonesian coup d'état in 1965 and was replaced by the pro-Western Suharto.[4][5] The American mining company Freeport-McMoRan began exploiting Western New Guinea's copper and gold deposits.[23]

Following the Act of Free Choice plebiscite in 1969, West Papua was formally integrated into the Republic of Indonesia. Instead of a referendum of the 816,000 Papuans, they were represented by 1,022 Papuan tribal representatives for the vote.[citation needed] While several international observers including journalists and diplomats criticized the referendum as being rigged, the United States and Australia supported Indonesia's efforts to secure acceptance in the United Nations for the pro-integration vote. In all, 84 member states voted in favor for the United Nations to accept the result, with 30 others abstaining.[24] Due to the Netherlands' efforts to promote a West Papuan national identity, a significant number[clarification needed] of West Papuans refused to accept the territory's integration into Indonesia. These formed the separatist Organisasi Papua Merdeka (Free Papua Movement) and have waged an insurgency against the Indonesian authorities, which still continues to this day.[7][25]


  1. ^ https://www.veteraneninstituut.nl/missie/nieuw-guinea/
  2. ^ Ron Crocombe, 282
  3. ^ Audrey and George McTurnan Kahin, p. 45
  4. ^ a b c d e f g "Operation Trikora – Indonesia's Takeover of West New Guinea". Pathfinder: Air Power Development Centre Bulletin (150): 1–2. February 2011. Retrieved 19 September 2013.
  5. ^ a b c d e f g h Platje, Wies (2001). "Dutch Sigint and the Conflict with Indonesia 1950–62". Intelligence and National Security. 16 (1): 285–312. doi:10.1080/714002840.
  6. ^ a b J.D. Legge, 402
  7. ^ a b c Bilveer Singh, West Irian and the Suharto Presidency, p.86
  8. ^ Soedjati Djiwandono, p. 131
  9. ^ Wies Platje, 297–299
  10. ^ a b J.D. Legge, 403
  11. ^ {{cite news  | last = Sibero  | first = Tarigan  | title = Heroic Story of Seizing West Irian (1)  | publisher = TNI  | date = May 3, 2006  | url = http: //www.tni.mil.id/news.php? q = dtl & id = 113012006111078  | accessdate = }}
  12. ^ Nikita Khrushchev, Memoirs of Nikita Khrushchev: Volume 3: Statesman (1953-1964), ed. Sergei Khrushchev, trans. George Shriver (Pennsylvania: Pennsylvania State Press, 2007)
  13. ^ https://www.rbth.com/international/2017/01/21/how-russia-helped-indonesia-annex-western-new-guinea_685151
  14. ^ https://www.historischnieuwsblad.nl/nl/artikel/32211/russische-duikboten-voor-nieuw-guinea.html
  15. ^ “Topi ikh vsekh!”, Tekhnika Molodezhi, No. 11 (1995)
  16. ^ “Perebutan Irian Barat: Di Balik Konflik RI-Belanda 1962”, Suara Pembaruan, 2005
  17. ^ Perspectives on Military Intelligence from the First World War to Mali: Between Learning and Law, T.M.C. Asser Press, 21 Jul 2017, page 91
  18. ^ Matthijs Ooms, “Geheime Sovjetsteun in Nieuw-Guinea”, Marineblad, Vol. 122, No. 5 (2012), 26.
  19. ^ e https://kclpure.kcl.ac.uk/portal/files/45249388/Active_Soviet_military_support_for_Indonesia_during_1962_West_Irian_Crisis.docx
  20. ^ "Maritime-sar – Militaire Luchtvaart Nederland". militaireluchtvaartnederland.nl. Retrieved 23 May 2016.
  21. ^ Soedjati Djiwandono, Konfrontasi Revisited, p. 135.
  22. ^ J.D. Legge, 403–404
  23. ^ Ron Crocombe, 285
  24. ^ Ron Crocombe, 284
  25. ^ Ron Crocombe, 286-91