139 Curtin to Churchill
Cablegram Johcu 60  CANBERRA, 18 March 1943
MOST IMMEDIATE MOST SECRET
On 19th January I addressed to Washington, for transmission to President Roosevelt and yourself, a cablegram urging, in view of the lessons of the use of airpower in the New Guinea campaign, that 1,500 additional operational and Soo additional transport aircraft be made available to the South-West Pacific Area as soon as possible in 1943.  2. Mr. Sumner Welles undertook to transmit these messages to both of you immediately, but I have had no reply from either the President or yourself I referred to it again on 17th February in my Johcu No. 56.  3. Since I first approached you, there has occurred the Battle of the Bismarck Sea which resulted in the virtual annihilation of a Japanese convoy attempting to reinforce Lae and Salamaua.  This victory was a further practical demonstration of the case urged by me on 19th January.
4. The Intelligence Reports have recently indicated that the Japanese are intensively consolidating an are of air bases extending through the Netherlands East Indies, Portuguese Timor, New Guinea, Rabaul and the Northern Solomons, to the Marshall Islands.
5. It would appear from their air superiority in the operations in Malaya and the Netherlands East Indies that they under-rated the strength that could be brought against them. Since their bitter experiences in the Solomons, New Guinea and the Bismarck Sea, they are apparently determined to secure air superiority in the arc I have described and concentrations of land forces are taking place.
There is no evidence of air concentrations so far, but the air bases will be sufficient to enable a strength of 1,500 to 2,000 planes to be operated in these regions.
6. I shall be glad to be informed of the air strength that it is proposed to provide in the South-West Pacific Area to ensure that the initiative in the air is retained by the United Nations and that the Commander-in-Chief, South-West Pacific Area, is in a position to deter and, if necessary, severely repulse any attempts by the Japanese to raid heavily by air and naval forces territories in our possession.
7. It is noteworthy, and also a tribute to the effectiveness of the forces engaged, that, in the Battle of the Bismarck Sea, it was possible to concentrate only 136 aircraft for this attack. The renewal of attacks on Darwin and reconnaissance of the Northwest Coast indicate the paramount importance of sufficient strength being able to ensure air superiority along the whole line of contact with the enemy and at other vulnerable points on our coastline, especially in the West. Of particular importance is the vital base of Fremantle where, owing to the depletion of the Eastern Fleet, a heavy attack of the tip and run variety might be carried out by Naval bombardment and carrier-borne aircraft.