|Attack on Force Z|
|Japanese air attack|
|After the action|
Around that time, news came in Pearl Harbor had been attacked and eight U.S. battleships had been sunk or disabled. Pre-war planning had presumed (wrongly) the U.S. Pacific Fleet would have moved to Singapore to reinforce the British when war broke out. That was now impossible. Philips had concluded in an earlier discussion with U.S. General Douglas MacArthur and Admiral Thomas C. Hart that his two capital ships were of insufficient strength to confront the Japanese. However, with the Japanese threatening to overrun Malaya, Philips was pressed to use his ships in an offensive role and he assembled his flotilla to intercept and destroy Japanese invasion convoys in the South China Sea.
Admiral Philips knew the local Royal Air Force unit could not guarantee air cover for his ships as they were equipped with limited numbers of aging fighters (although there was one squadron, RAAF 453 Squadron with Brewster F2As, standing by at Sembawang to provide close cover; given how poor the F2A's performance was, their value is in doubt) and their airfields were threatened by the Japanese land attacks. He elected to proceed anyway because he thought that Japanese forces could not operate so far from land. He also thought that his ships were relatively immune from fatal damage via air attack, since, up to that point, no capital ship at sea had ever been sunk by air attack (the largest vessel sunk to date by aircraft alone was a heavy cruiser); thus, "he was probably half-right in his assessment". Moreover, he was unaware of the quality of Japanese torpedo bombing and torpedo aircraft, both vastly superior to RN examples. In addition, like the majority of RN officers, Phillips did not believe Japanese forces were any good.
No. 453 Squadron RAAF was to provide air cover to Force Z, but they were not aware of the position of Force Z, and a radio signal was only sent out (by Repulse) an hour after the Japanese planes attacked. The plan of Flt Lt Vigors to keep six aircraft over him during daylight had been turned down by Phillips. Vigors commented I reckon this must have been the last battle in which the Navy reckoned they could get along without the RAF. A pretty damned costly way of learning. ..... Phillips had known that he was being shadowed the night before, and also at dawn that day. He did not call for air support. He was attacked and still did not call for help. Daytime air cover off the coast was also offered by Clouston of 488 Squadron, but his plan "Operation Mobile" was rejected.
At 0713 on 9 December, Force Z passed the Anamba Islands to the east, and turned to a new course of 330 degrees, later changing to 345 degrees. Force Z was overflown by two Japanese reconnaissance aircraft, but not reported, before being spotted by Japanese submarine I-65 at 1400 on 9 December, which shadowed the British ships for five hours, radioing their positions. Phillips was unaware he was being shadowed by the submarine. After this report, Vice Admiral Jisaburō Ozawa, in command of the invasion force, ordered most of his warships to escort the empty transports back to Cam Ranh Bay in southern Vietnam.
About 1730, just a half hour before sunset, the force was spotted by 3 Aichi E13A (Jake) seaplanes , which had been catapulted off the Japanese cruisers Yura, Kinu and Kumano escorting the transports. These aircraft continued shadowing. At about 1830, Tenedos was detached to return to Singapore, because she was running low on fuel, with instructions to contact Rear Admiral A. F. E. Palliser, detailed to act as liaison to RAF in Malaya, Phillips' intention no longer to attack Singora, while Phillips himself changed course at 1900 toward Singora, to deceive the shadowing aircraft, then south toward Singapore at 1015, when darkness covered him. Tenedos dutifully reported at 0800, thereby preserving the secrecy of Phillips' position.
A night attack was attempted by the Flotilla because they feared that the British battleships would find their invasion force, but bad weather prevented them from finding the ships and they returned to their airfields at Thủ Dầu Một and Saigon about midnight.
Return to Singapore
On the way back, they were spotted and reported by the Japanese submarine I-58. I-58 reported that it had fired 5 torpedoes and missed, and then lost sight of the force 3 hours later. The British force did not see the torpedoes, and never knew they had been attacked. The report from the I-58 reached the 22nd Air Flotilla Headquarters at 0315, and ten bombers of the Genzan Air Corps were dispatched at 0600 to conduct a sector search for the ships. The Flotilla left their airfields about an hour later, and were ordered to proceed to the best estimated position of the ships.