The island of Singapore, with a land of area of less than 600 square kilometres, lies off the southern tip of the Malayan Peninsula. With its strategic location and natural deep water harbour straddling the lucrative trade route between Asia and Japan, its small size and lack of natural resources makes it a natural objective for anyone with intentions of controlling the trade in the region. As such, colonial power Britain, which has controlled the island and its Malayan hinterland since the mid-19th century, saw Singapore as a vital interest and the best choice to build a naval base in the 1930s. With war clouds looming, the Sembawang Naval Base was completed with great fanfare in the 1930s.

Imperial Japan, with territorial ambitions over all of Asia, saw the Naval Base as a significant threat and Singapore as a vital piece of its Greater East Asia Co-Prosperity Sphere. With the threat of war approaching the late 1930s, plans were drawn up to mount an land assault on Singapore via it's Malayan hinterland. When war broke out in December 1941, attacks were launched across a wide swath of Asia, including Malaya, Singapore, Burma, Borneo and the Philippines. A significant amount of Imperial Japanese Army and Navy resources were devoted to the invasion of Malaya and Singapore alone, underscoring how important the Japanese viewed the capture of the strategic island.

The Imperial Japanese Navy Air Force (IJNAF) was heavily involved in the assault on Singapore, beginning on the 8th of December 1941 to the 15th of February 1942. The unit involved was the IJNAF's 22nd Air Flotilla based in newly-occupied Indo-China. Beginning in November 1941, 3 Kokutais (Flying Groups/Regiments) of long-range land-based attack bombers were based around the Saigon area to prepare and support the forthcoming invasion of Malaya, Singapore and Borneo. Each Kokutai usually consisted of 30+ aircraft, subdivided into Chutais (Companies) of 8-9 aircraft each and then further subdivided into flights of 3 aircraft. As of 7 December 1941, the strength of the 22nd Air Flotilla comprised of:

Genzan Kokutai - 36 Mitsubishi G3M2/3 Nells (Type 96 Rikko or Land-Based attack bomber) based at Saigon

Mihoro Kokutai - 36 Mitsubishi G3M2/3 Nells (Type 96 Rikko) based at Thu Dau Moi

Kanoya Kokutai (Detachment) - 27 Mitsubishi G4M1 Bettys (Type 1 Isshikirikko) based at Thu Dau Moi

Attached Fighter Unit - 25 Mitsubishi A6M2 Zeros based at Soc Trang, 12 Mitsubishi A5M4 Claudes at Saigon

In addition 12 Mitsubishi C5M Babs reconnaisance/observation aircraft were also based at Soc Trang.

It was a testimony to the design of their aircraft and propulsion systems (along with the sacrificing of weight such as armour) that the Nells, Bettys and Zeros were able to fly the 600+ miles to Singapore and back without any problem. In fact, the Genzan Kokutai Nell that located and directed all 3 bomber Kokutais to attack the HMS Prince of Wales and Repulse stayed aloft for a total of 12 hours without refueling!

In addition to interdicting the sea lanes around Singapore as well as long range patrols in the South China Sea (which they encountered and shot down a number of Allied patrol planes), the 3 bomber Kokutais, with their escort and reconnaisance elements, were heavily involved in attacking Singapore proper. The following is a summary of IJNAF operations over Singapore, during the combined aerial blitz by the Japanese Army and Navy Air Forces in January 1942.

- Bloody Shambles Vol 1, Christopher Shores, Brian Cull and Yasuho Izawa (Grub Street Books)
- Mitsubishi Type 1 Rikko Betty Units of World War 2(Combat Aircraft 22), Osamu Tagaya (Osprey Publishing)

Map of Singapore Island scanned from "British Combat Aircraft in Action since 1945", David Oliver (Ian Allan Printing Ltd)