WITH the Japanese evacuation of Guadalcanal on 8 February 1943 the United States Pacific Command had attained its objective in the first limited offensive against the enemy forces in the area—the capture of Henderson Field and the elimination of Japanese forces on the island. The neighbouring South-West Pacific Command had also attained its first objective in New Guinea with the capture of Buna in January. From February to June both commands made preparations for major offensives to drive the Japanese out of their bases on New Guinea and in the Solomons. The ultimate aim of both campaigns was to destroy or at least render ineffective the major enemy base at Rabaul. The drive through New Guinea, under the control of the South-West Pacific Command, was directed against Lae and Salamaua. The South Pacific Command was ordered to destroy the enemy air forces on New Georgia and to establish a base at Empress Augusta Bay on Bougainville, from which a major air offensive could be launched against Rabaul.

Until June there were no important land operations in the Solomons. The only forward move made by the American forces was to the Russell Islands, 50 miles north of Guadalcanal, which were occupied without opposition on 21 February. The enemy had maintained a small force there for a short time earlier in the year but had withdrawn it when Guadalcanal was evacuated. The Americans constructed two airfields and a naval base on the islands. The first airfield came into operation on 25 May. As a result enemy shipping in the Buin anchorages came within closer range of American dive-bombers, and it became possible to give fighter protection to bombing strikes against the New Georgia area.

The operational strength of the RNZAF at Santo was increased in the early months of 1943 by the addition of No. 9 Squadron, which moved up from New Caledonia in March, and No. 14 Fighter Squadron, which came from New Zealand at the beginning of April. No. 9 Squadron, besides providing a reserve of aircraft and aircrews for No. 3 Squadron, carried out shipping escorts in New Hebridean waters and special searches whenever enemy submarines were reported. On the whole, operations were uneventful and no enemy vessels were seen.

No. 14 Squadron, as soon as it settled in, took over the fighter defence of the island. Operating under orders of the United States Interceptor Command, it maintained twenty-four-hour readiness in anticipation of sneak raids by Japanese aircraft. Frequent scrambles were ordered, both by day and by night, to intercept unidentified aircraft, but no hostile planes were met. The only occasion on which an enemy machine was identified was on a night in late May, when four pilots were ordered up to intercept a Japanese bomber which had dropped bombs on Segond Channel. No interception was made, as the radar unit controlling the operation lost contact with the enemy at the crucial moment.

No. 3 Squadron's operations from Guadalcanal in the weeks that followed the Japanese evacuation were also relatively uneventful. The period was not marked by important operations by the Allied air forces, although it was not entirely devoid of action. American air attacks against enemy bases and shipping to the north occurred almost daily. The air force was employed by the Americans as the primary offensive arm in an attempt to close the enemy shipping routes between Buin and New Georgia and to prevent the enemy air force from permanently using its forward airfields at Munda and Vila.

The task of the Allied air forces was to strike at the bases and airfields in the Buin-Kahili area, the shipping lanes between Buin and New Georgia, and the forward airfields at Vila and Munda. The effectiveness and weight of the Allied bombing strikes increased as the air force bases on Guadalcanal were steadily reinforced. Munda and Vila were kept unserviceable by repeated bombing and could be used by the Japanese only as staging bases for their spasmodic attacks against Guadalcanal and the Russells.

The only engagement which No. 3 Squadron had with the enemy in February, after the Japanese evacuation, occurred on the 13th when a Hudson on patrol fought off an attack by three Japanese fighters. A major contact with enemy shipping was made on the 27th when a Hudson sighted two warships and a cargo ship off Vella Lavella. American bombers were directed to the convoy and set two of the ships on fire.

Twice in February Hudsons sank enemy barges carrying troops and supplies, one off southern Choiseul and another on Kolo Lagoon in the south-east of the New Georgia Group.

Routine operations were daily search patrols, three in the morning and five in the afternoon. Besides these, RNZAF Hudsons were employed on weather reconnaissance flights in the Buin area immediately before American bombing attacks against shipping there. When returning from these flights in the early hours of the morning the Hudsons generally dropped bombs on Munda or Vila.

In March No. 3 Squadron was still employed on sea patrols and flew a total of 249 sorties during the month. Only four Japanese ships were sighted on these flights, and the Hudsons were engaged on four occasions with enemy aircraft without loss to either side. The squadron also took part in minor air attacks against the enemy barge staging points on Viru, and continued to carry out nuisance raids on Munda. Although the damage that could be done by a Hudson's bombs was relatively small, every crew was given the opportunity to take part in bombing raids whenever possible so that the men had the satisfaction, after endless hours of monotonous patrolling, of hitting at the enemy.

On the nights of 20–21 and 21–22 March, when American bombers made heavy attacks on enemy shipping and laid magnetic mines off the coast of southern Bougainville, Hudsons acted as navigation planes, dropping flares to guide the bombers back to Guadalcanal. This practice was extended during April. The Avengers and Dauntlesses which formed the major part of the American attacking forces did not carry navigators, and the task of navigating the plane, as well as flying it to and from the target through several hundred miles of darkness, imposed a great strain on the pilots. The dropping of flares at intervals ahead of the bombers on the way back to base eased the strain and resulted in fewer American aircraft being lost. In this, as in other instances, New Zealand navigators achieved high praise from the Americans for their efficiency and the accuracy of their work.

During April the squadron flew a total of 197 searches and other missions. Only four contacts with enemy ships were made, but a total of 71 enemy aircraft were sighted on 34 different patrols. Hudsons were in action against enemy aircraft on five occasions.

The first enemy plane to be shot down by the RNZAF was destroyed on 2 April by a Hudson captained by Flying Officer McCormick.¹ The Hudson was on patrol in the afternoon north of Choiseul and the enemy aircraft, a float-plane, was seen ahead of it flying in the same direction. McCormick, remembering his orders to avoid combat as far as possible, had to consider whether he would keep to his patrol or alter course to avoid overtaking the enemy. He decided to keep on and close with the Japanese aircraft. The enemy was taken unawares and was shot down in an attack from astern by the Hudson's front guns and crashed into the sea.

The most notable feature of the patrols by No. 3 Squadron in early April was the number of sightings of Japanese submarines. Two of the aircraft on reconnaissance on the morning of 1 April saw submarines to the north of Santa Isabel, but on both occasions the vessels crash-dived before the aircraft could attack. The following afternoon another Hudson sighted one surfaced 120 miles south of Simbo Island. It attacked as the submarine crash-dived, but the bomb-release gear did not function. A second bombing run was made a minute later and two depth-charges and two bombs were dropped along the submarine's track, but no results were observed. A second sighting was made by another Hudson the same afternoon, 55 miles south of Teop Harbour, Bougainville. The submarine crash-dived before the Hudson could reach it. Late in the afternoon of 3 April a Hudson captained by Flight Sergeant Marceau,¹ sighted a large submarine on the surface off the coast of Vella Lavella. The aircraft approached it under cover of a rain squall, losing height to approximately fifty feet. When it broke through the squall the submarine was just ahead of it. The conning tower was open and three Japanese were standing on it. The aircraft attacked before the vessel could crash-dive. One depth-charge exploded practically on the bow, a second midway between the bow and the conning tower, and a 250-pound bomb exploded between the conning tower and the stern, blowing the stern to pieces. Immediately after the attack the water was covered with oil and wreckage.

Throughout April No. 3 Squadron continued to carry out routine patrols on a slightly reduced scale, some of the longer searches being taken over for a few days by American B17s. Most of the patrols were uneventful, with the exception of frequent afternoon sightings by Hudsons of Japanese float-planes in the vicinity of Simbo Island.

On the afternoon of 10 April a Hudson was attacked by a float-plane 106 miles north of Simbo. The enemy fired several bursts at 800 yards' range without scoring any hits, and then broke off the action. Two float-planes were seen on the 12th but did not attack. Two days later a Hudson on afternoon search was twice intercepted. It was attacked first by a float-plane 74 miles off Simbo and drove the enemy off by fire from its turret guns. Shortly afterwards it was attacked by a second enemy aircraft, but eluded it and returned safely to base.

In an effort to destroy the float-planes, American fighters were sent out to escort the patrolling Hudsons in the Simbo area. On the afternoon of 16 April the Hudson on afternoon search was accompanied by four P38s. An enemy plane was seen in the usual area about ten miles away, but the fighters did not see it and all efforts to attract their attention to it failed. The next day four fighters patrolled the area on their own but failed to make contact.

On the afternoon of 21 April a Hudson captained by Flying Officer Golden,¹ on routine patrol to the north-west of Guadalcanal, was ordered to bomb the village of Malevoli on Choiseul. The coastwatcher there had reported that the Japanese had occupied the village and established a radio station in the church. The Hudson came over the target and made two bombing runs at 500 feet. On the first run it dropped two bombs, only one of which exploded, 20 yards to the south-east of the target. On the second run one bomb failed to release and the other exploded on a cliff face 20 yards north-east of the church. The Hudson made another run, but the remaining bomb could not be released and the target was strafed with machine guns. Tracer hit the roof of the church but failed to set it on fire. After the attack American fighters strafed the area, leaving stores and buildings smoking.

Throughout February and March the Japanese air force in the Solomons had remained comparatively inactive, apart from minor attacks against Guadalcanal and the Russells and on American shipping. In the first week in April reserves were flown in from Rabaul and the enemy took the initiative. On 1 April thirty to forty enemy fighters made an offensive sweep over the Russells and were engaged by forty-one American fighters. Sixteen enemy aircraft were shot down and six American fighters lost.

This was the first major action in which No. 52 Radar Unit, RNZAF, took part. Its success in directing the Allied fighters on to the raiders was afterwards recognised in a letter of commendation from comairsopac.

During May the position of the enemy air force in the Solomons deteriorated considerably. American intelligence estimated that the enemy fighter and bomber strength had fallen from 102 aircraft on 15 May to 62 on the 29th. The Japanese still had more than 250 aircraft at Rabaul at the end of the month, providing a large reserve on which their forces in the Solomons could draw if necessary. Day and night reconnaissance by their search planes over the Solomons continued to be thorough, enabling them to bring their reserves from Rabaul to any area which was particularly threatened by the Allies. At the same time the Allied forces at Guadalcanal were steadily being built up and the American commander was able to employ striking groups of up to a hundred bombers and fighters and interception groups of over a hundred fighters.

No. 3 Squadron continued in its role as a reconnaissance squadron, its operational commitment being seven routine searches daily. Only two sightings of enemy ships were reported during the month and on twelve occasions enemy aircraft were seen. Hudsons were attacked on four occasions by enemy aircraft without loss to either side.