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Appendix S

Summary of RENO III, Outline Plan for Operations of the Southwest Pacific Area to Reoccupy the Southern Philippines, prepared by GHQ, SWPA, 20 October 1943

Our strategic objective is the isolation of Japan from the Malay-NEI area. Present tasks are to:

1. Seize or neutralize E NG as far W as Wewak, and including the Admiralties and the Bismarck Archipelago. Neutralize, rather than capture Rabaul.

2. Advance along the N coast of NG as far W as the Vogelkop by AB-amphib jumps.

3. Prepare to seize Mindanao by AB-amphib opns.

Our eventual task is to reoccupy the S PI, and by subsequent opns isolate Japan from the Malaya-NEI area.

Accomplishment of the tasks presently assigned by Quadrant decisions initially requires opns along 2 general axes.

1. NW along the NG coast from Vitiaz St in order to advance land-based air.

2. W through the N Solomons–New Ireland, including the Admiralties, to a junction with the W axis in order to complete the isolation of Rabaul and obtain necessary bases for naval support of opns along the axis.

The eventual task requires seizure of Mindanao, followed by opns in conjunction with other Theaters to sever sea and air communications between Japan and Malaya–NEI area. These opns require attacks against strongly defended air and naval bases. Our advantages lie in superior equipment and potentially superior strength in the air and on the sea, but amphib equipment will be limited pending cessation of the offensive in Europe. On the assumption that the Japanese will maintain their strategic defense, our advantages must be fully utilized to deal him a succession of blows precluding his recouping of air and sea forces after each of his defeats and so permit destruction of his bases in detail.

The general scheme of maneuver is to advance our land-based bomber line rapidly W along the land masses on NG and the PI by successive occupation of the minimum bases required. Hostile strength is by-passed wherever practicable to avoid costly and time-consuming opns; our flanks are protected by air opns; and necessary advanced naval bases are established under protection of land-based aviation in order to extend the range of naval action. Destructive air attacks are employed to soften up objectives and to gain air superiority. Hostile naval forces and shipping are destroyed along our line of advance to prevent reinforcement. Ground forces are displaced forward by air and amphib movements. Air and naval forces are established at each objective and the process is then repeated, neutralizing by air and sea action hostile concentrations that may be by-passed. The number of objectives is decreased and the length of bound increased by use of a/c carriers to provide close air support. The same result is

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aided by extending the destructive effort of bombers through use of air envelopment to advance the fighter line through inland fields established and maintained by air support.

Sequence and timing are based on present enemy dispositions and are subject to change dependent upon enemy reaction and success of our opns. Timing is also dependent upon the availability of means, particularly amphib forces, and the timing given herein is based on an estimate of means to be available as a result of quadrant.

Logistic support is provided by the SOS of SOPAC and SWPA. As opns progress to the NW, ports and supply bases are advanced by corresponding bounds. Heavy shipping is used wherever unloading facilities are available and amphib craft are used for assault elements and where the use of heavy shipping is impracticable. Trans-Pacific shipping is diverted directly to newly established bases along the line of advance. Bulk petroleum is transported forward in small tankers to points where the tactical situation permits the installation of bulk storage tanks.

Known requirements in items of special equipment, major units, air and service units, are set forth in the “1944 Troop Basis, GHQ, SWPA, 9 October 1943.”

Phase I

Naval bases are required in the Bismarcks to support subsequent opns into W NG. Direct attack to capture Rabaul will be costly and time-consuming. Anchorages and potential air and naval bases exist at Kavieng and in the Admiralties. With the capture and development of such bases, Rabaul can be isolated from the NE. Direct attack into the Wewak area would also be costly in means and time. Presently occupied a/mes do not provide sufficient protection to bypass the area, but potential air bases exist in the Hansa Bay area, from which the isolation of Rabaul can be completed and opns to the W of Wewak be protected.

Scheme of Maneuver:

A. Target date t Feb 44. SWPA forces seize the Hansa Bay area by amphib opns with AB support. Direct air support is provided from the Vitiaz St–Ramu Valley a/mes. Shore-to-shore opns secure the mouth of the Sepik to contain enemy forces in the Wewak area. Advance bases are established for the support of opns in the Humboldt Bay area. Hostile forces in the Malang-Alexishafen area are isolated and the area later occupied by holding forces from the Huon Peninsula–Ramu Valley.

B. Target date 1 Mar 44. Kavieng is occupied by an amphib opn of SOPAC Forces. The opn is preceded by intensive air and naval neutralization of the Rabaul area and has the direct support of heavy elements of the PacFlt. Air support comes from W New Britain and from carriers. General air support is from NG, Nor-Sols, and Kiriwina and Woodlark. Interference from hostile fit is covered by opns of CENPAC and in the Mandates and by the PacFlt. Air elements are then established for support of opns against the Carolines and Rabaul.

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Light naval forces are established for support of opns to the W and to help blockade Rabaul.

C. Target date 1 Mar 44. The Admiralties are taken by amphib opns of SWPA Forces staging through Vitiaz St. Direct air support comes from the Vitiaz St area and from CVEs. General air support from the Markham–Ramu area. Air and naval forces are established in the Admiralties, and base facilities developed, for the support of opns along the N coast of NG.

D. When the blockade has sufficiently reduced the defensive capacity of the enemy garrison, Rabaul is occupied at a date and by forces later to be determined, and appropriate base facilities are established.

Forces required:

Garrison Assault Air Naval
2 US inf div 7 US inf div HB 5 grps 15 APD 2 CV
6 Austn divs 2 US Para RCTs MB 10 grps 16 APA 9 CVE
1 NZ div 3 MarDefBns LB 11½ grps 5 AKA 4 CA
Aust armd bde Day F 16 ½ grps 85 LST 4 CL
Night F 14 grps 60 LCI 58 DD
Trp Carr 6¼ grps 105 LCT 164 PT
Photo & Recce 8½ grps (and small craft)

Naval strategic support will be elements of the US Pac Flt as designated by the JCS.

Phase II

(Initiated 1 Jun 44)

Advanced air and naval bases are required at an intermediate point on the N coast of NG for the support of opns into Geelvink Bay and protection of the L/C thereto. Air bases in Wewak are too distant from the Geelvink area to support attacks and are held .in great strength by the Japanese. Costly and time-consuming opns will be avoided by by-passing and neutralizing the Wewak area. Partially developed sites exist in the Humboldt Bay area which may be improved to meet essential requirements. The concentration of hostile a/mes in the Banda Sea area requires establishment of flank protection and support for opns into Geelvink Bay. Occupation of the Aroe–Kai–Tanimbar Islands provides a difficult but feasible means of securing this protection and support.

Scheme of Maneuver:

A. Humboldt Bay, target date 1 Jun 44. An amphib opn from NG bases with AB support seizes objectives in the Aitape–Humboldt Bay area, by-passing Wewak. Air support is provided from the Markham–Ramu Valley, Hansa Bay, and the Admiralties. Close support comes from CVEs. Inland air bases are established in the upper Digoe-Fly Rivers by air transport as practicable. Adv bases are established in the Humboldt Bay area for support of opns into the Geelvink–Vogelkop area. Forces in the Aitape area initiate infiltration opns from the W toward Wewak and finally occupy it when hostile resistance has deteriorated.

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B. Arafura Sea. 1 Jun 44. Preceded by aerial neutralization of Timor a/mes, the Aroe-Kai-Tanimbar Islands are occupied by an amphib assault of Austn troops supported by AB elements. General air support is provided from Darwin area, convoy cover from Merauke—Horn Is—Arnhem Bay, and by CVEs. Air bases are promptly developed.

Forces required:

Garrison Assault Air Grps Naval
6 Austn inf divs 4 US inf divs 8 HB 2 CV 15 APD
1 NZ inf div 2 Austn inf divs 12 MB 7 CVE 5 APA
5 US inf divs 1 US AB div 11¾ LB 4 CA 84 LST
1 Austn armd bde 2 para RCTs 22 ½ Night F 6 CL 60 LCI
1 MarDefBn 18½ F 83 DD 145 LCT
8¼ Trp Carrier 8 PF
11 Photo Recce 168 PT

Naval strategic support will be from the US PacFlt as designated by the JCS to insure noninterference by hostile heavy fit elements.

Phase III

Initiated 15 Aug 44)

Major naval and air bases are required in W NG to support opns to the NW. Potential sites are available in the Geelvink Bay—Vogelkop area. Opns require protection against major enemy fit elements by the US Flt.

Scheme of Maneuver:

A. Geelvink Bay, 15 Aug 44. Anchorages, a/mes, and potential base sites are seized by an AB overseas landing, staged in NG. Babo and Nabire are neutralized by air staged through Aroe-Kai-Tanimbar. Direct air support is provided from the Humboldt Bay area through inland air bases established and maintained in favorable locations by air transport, and also by CVEs. Major air and naval base development is instituted for support of opns against Mindanao.

B. Vogelkop Area, 1 Oct. 44. The Sorong and Kabui Bay areas are occupied by an amphib opn with AB support. This opn is launched as soon as air support is available from Geelvink Bay bases. The Klamono oil field is occupied and intensively developed as a source of bunker fuel.

Forces required:

Garrison Combat Air Groups
7 Austn inf divs
1 NZ inf div
4 US inf divs
1 Austn armd bde

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Naval Combat Amphib Craft
2 CV 15 APD
6 CVE 16 APA
4 CA 5 AKA
6 CL 54 LST
64 DD 60 LCI
183 PT 175 LCT

Phase IV

(Initiated 1 Dec 44)

Advance into Mindanao requires a broadening of the front for deployment of air forces, protection for flanks, and establishment of advance bases for support of sea and AB movements. These requirements can be met by establishing air and light naval elements on Halmahera and/or Morotai. Menado must at least be denied to the enemy and Palau must be occupied by either CENPAC or SWPA forces. The Ambon area must be neutralized by air action, but may have to be occupied if hostile strength in the NEI requires such action.

Scheme of Maneuver:

A. Halmahera-Menado, target date 1 Dec 44. A/mes or sites therefore on Halmahera and/or Morotai are occupied and Menado seized by amphib opns from Geelvink Bay, supported by AB elements. Air and naval forces are established for flank protection and support of subsequent opns to seize and occupy Mindanao.

B. Ambon (contingent opn) , 1 Dec 44. In the event that hostile strength in the E NEI jeopardizes opns on Mindanao, it may be necessary to establish air and naval forces on Ambon. If required, this opn will be amphib, staged from Geelvink via the Dampier Strs, will seize enemy air bases on Ceram and Boeroe and capture Ambon. Enemy air forces on Timor are neutralized from Darwin, and general air support comes from Aroe–Kai–Tanimbar–Geelvink–Vogelkop areas.

C. Palau, 1 Dec 44, or 15 Jan 45 if Ambon is occupied. In the event that SWPA forces are assigned the task of occupying Palau, that group is seized by amphib opns with the direct support of the PacFlt, including strong carrier elements. Naval air elements are established on Palau for protection of the axis of advance against enemy air attacks from the N.

Completion of Phase III accomplishes the tasks presently assigned to the SWPA by the Quadrant decisions. Estimates of forces required to accomplish Phases IV and V of this plan are of problematical value in view of the certainty of major changes in the Pacific situation and in the availability and types of means available for the carrying out of Phase III. A tentative estimate of divs

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for Phases IV and V have been shown in Annex 3, but only as a basis for 44 troop estimates. For Phase IV these are:

Garrison Combat
5 Austn inf divs 7 US inf divs
4 US inf divs 1 Para RCT
1 Austn armd bde 1 MarDefBn
2 US inf divs for possible opns in Jan 45

No estimates of naval or air means can be given at this time.

Phase V

(Initiated 1 Feb 45)

Occupation of Mindanao requires an attack by major forces of all components over a widely spread area in order to achieve surprise and disperse the defensive effort. Employment of air envelopment on a major scale, using equipment now in prospect, becomes feasible upon establishment of adequate bases in the Geelvink-Vogelkop area. Present guerrilla organization provides necessary terminal facilities. Prompt and ample seaborne reinforcement of initial assault is essential. Consolidation of the S PI requires occupation of covering positions in the islands to the SW and N of Mindanao and the establishment of major forces thereon preparatory to subsequent opns. Inasmuch as the enemy must defend Mindanao with all the means at his disposal, prompt consolidation and subsequent exploitation should meet a minimum of effective opposition.

Scheme of Maneuver (see also map in Annex 2-e)

A. Occupation of Mindanao, target date i Feb 45. Beachheads and a/mes through the N and NW portions of Mindanao are seized by major combined AB-amphib opns with carrier based air support. An AB invasion in strength is staged in New Britain and E NG via W NG. Guerrilla forces are employed to seize a/mes on which to land AB forces. Landing opns seize beachheads in the proximity of a/mes. Paratroops are dropped on a/mes. Light air elements are flown in to support the advance of occupation forces and protect subsequent landings. Initial landings are promptly reinforced by air transport.

B. Consolidation of Southern PI: The Mindanao Occupation Force follows the AB invasion closely along the main line of advance to beachheads in our possession. All types of aviation are established in order to maintain air superiority and cover the occupation of Zamboanga and Davao and positions in islands to the SW and N. The L/C W of the line Palau-Vogelkop is kept open by naval elements from advanced bases in the Vogelkop area, supported by air from Palau, Menado, and Halmahera-Morotai. Additional forces of all arms are rapidly established on Mindanao in preparation for opns to reoccupy the northern PI and to isolate Japan from the Malay-NEI.

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Logistic bases are set forth on map of Annex 4–f. Ground forces required (a suggestion rather than definite estimate) :

Garrison Combat
5 Austn inf divs 4 US inf divs
4 US inf divs 2 US AB divs
3 US inf divs for contingent opns 1 para RCT
1 Austn armd bde 2 MarDefBns

Forces for the consolidation are undetermined. Impossible to estimate at this time the naval and air forces required.