British forces in Singapore did outnumber the Japanese (85,000 vs 30,000), but they were poorly trained and severely under-equipped. The British made several fatal strategical mistakes as well. Lieutenant General Arthur Percival, General Officer Commanding for Malaya, was ordered by field marshal Wavell to never surrender Singapore. But Percival (who was in Singapore) made the decision to surrender when it seemed like defeat was inevitable.

The Australian battalions were fresh recruits with zero battle experience, similar with the Malay battalions and straits settlement volunteers. This accounted for 15 out of 49 battalions. The newly deployed British 18th infantry division was similarly inexperienced.

In contrast, the Japanese 5th and 18th division were war veterans from the Sino-Japanese war. There was also the imperial guard division, which although lacking in battle experience was a highly-trained and disciplined force. The Japanese forces only suffered minor casualties throughout the Malaya campaign while the British forces were constantly routed. The British divisions that managed to retreat to Singapore thus suffered heavy losses and were severely undermanned.

Singapore’s large naval coast guns were fitted with armour piercing shells to repel naval ships, which was ineffective against the Japanese infantry. High explosive shells were in short supply. Thus the contribution of the naval guns to the defence was inconsequential.

British artillery were given orders not to fire on the Japanese troops massing on the opposite side of the Singapore strait to conserve ammo for the main Attack. The sultan’s palace provided the Japanese with a bird’s eye view of Singapore and was not targeted by artillery due to its symbolic value, providing valuable intel to the Japanese. The Japanese easily spotted British forces in the north-west and began bombarding them with artillery in preparation for an amphibious assault, and no British counter-artillery barrage was conducted.

Percival wrongly predicted that the Japanese forces would land in the north-east and committed his best troops there, including the full-strength British 18th division. This was even though he knew the japanese artillery was targeting the north-west and was advised by Marshall Wavell that the Attack would likely come in the north-west.

As such, the entire north-west sector was defended by 3 undermanned Australia battalions with no defence works, and spread over a 18km front split by a river. When the Japanese landed at sarimbun beach on 8 February 1942 with 16 battalions, the 3 battalions of Australians were easily surrounded, bypassed or overrun.

After receiving reports of the Japanese landing in the north-west, Percival still remained convinced that the Japanese would attempt another landing in the north-east with the majority of their forces. He reinforced the north-west sector with only 2 undermanned battalions and held the full-strength 18th division in reserve. Meanwhile, the Japanese were ferrying their armoured divisions and artillery across the Singapore strait uncontested.

Poor communications between the British forces led to many field commanders incorrectly believing their lines were broken and ordering their troops to retreat and thus ceding ground to the Japanese. The Japanese thus captured Bukit Timah, the main storage site for British food and fuel. They also began to capture the reservoirs supplying the British forces with water.

The RAF Tengah, Seletar and Sembawang air bases were bombarded by japanese artillery and became non-operational early on during the invasion, thus the Japanese had complete air superiority over Singapore. The Japanese Air Force began attacking the city center and the British were running out of anti-air ammunition and could not repel them.

On 13th February 1942, the Japanese repaired the causeway and could now move their tanks into Singapore.

On 15th February 1942, Percival met with his senior commander and presented 2 choices, an immediate counter-Attack to recapture their supplies and water, or surrender. All commanders felt a counter-Attack would not succeed and opted for surrender.

Future analysis showed that the British actually had a decent chance of success if they counter-attacked. This would have allowed them to replenish their supplies and continue fighting. At this point, British and Japanese casualties were equal in number, but with the British forces being nearly triple the size they could have won the battle through attrition. Furthermore, the Japanese were actually in a similar supply situation and could not sustain their field operations for much longer.