Of course the key reason behind the short deadline was to get bombers in the air as fast as possible to prevent the Japanese from building a similar airfield on Guadalcanal, from which they would be able to attack Allied supply lines across the South Pacific.
The airfield was originally named Efate Field, Vila Field or McDonald Field but was later officially named Bauer Field after Lt-Col. Harold W. Bauer, a fighter pilot in the US Marine Corps who was lost at sea on 14 November 1942 after being shot down during the Battle of Guadalcanal.
A detachment of Seabees also went north to Havannah Harbour to construct a seaplane base to serve the squadron of PBY Catalina’s based there. The Seabees built two seaplane ramps, once again of coral, surfaced with Marsden Matting, and provided buoys for mooring 14 seaplanes. In addition to the ramps and moorings, two small piers, two nose hangars, one 40 feet (12 metres) by 100 feet (30 metres) seaplane workshop, four 5,000 gallon (19,000 litre) underground gasoline tanks, and housing facilities for 25 officers and 210 men in quonset huts were constructed. By June 1, the PBYs began operating from the new base, bombing Japanese positions on Guadalcanal.
Bombers took off from Efate within a month of the start of construction to harass the Japanese. But it soon became clear that Efate was not quite close enough to Guadalcanal for fighters to be able to provide fighter support to the bombers. That’s where Santo came into the picture.