The Cactus Air Force, primarily flying the rugged Wildcat fighter and the incomparable Dauntless divebomber, weathered every Japanese assault and emerged victorious.
The battle of Guadalcanal, the turning point of the Pacific War, centered around control of Henderson Field. The unfinished airstrip was captured the day after the US Marines landed, and was operational less than two weeks later. It was a rudimentary airfield, and the “Cactus Air Force” based there was short of aircraft, pilots, and supplies. But so long as the airfield remained in American hands, the Japanese could not send the heavy convoys they needed to recapture the island. The Americans had to keep Henderson Field operational in the face of constant attack from Japanese bombers and their Zero escorts, and even against battleship bombardment. The Cactus Air Force, primarily flying the rugged Wildcat fighter and the incomparable Dauntless divebomber, weathered every Japanese assault and emerged victorious.
As told by Mark Stille in his book Guadalcanal 1942-43, the key to defending Henderson Field was conducting effective interception of Japanese raids. The Marines had two primary sources of warning of incoming Japanese raids — coast watchers and radar. Every minute of early warning was crucial since enough time had to be gained to give the slow-climbing Wildcats time to assume their preferred interception altitude of 30,000 feet or more. Above 20,000 feet, the aircraft climbed only 500 feet per minute. If inadequate early warning was available, the result was usually a failed interception.
The system used to control the fighters was crude. Initially, it was a one-man show with the Marine air operations officer launching fighters when he received a radar contact. Once airborne, the Wildcats were not sent far from the airfield to conduct a radar-directed interception since the effective range of the radios on the Wildcats was only 10-15 miles. The air operations officer kept in touch with the airborne fighters through a salvaged aircraft radio mounted on his truck. The same officer also acted as an observer to identify enemy aircraft and sound the air raid alarm. In October, two naval officers who had graduated from the Navy’s fighter direction school arrived on Guadalcanal. They had to contend with the same unreliable radars and the lack of coordination between the 90mm gun batteries and the airborne fighters. The radar problem was largely solved by the ministrations of a single master technical sergeant who possessed the uncanny ability to tell how many and what types of Japanese aircraft were in a formation and their approximate altitude well before they arrived near Henderson Field. By November 1942, all the radars on the island were linked together and the coordination between fighters and antiaircraft guns was much improved. The system proved resilient enough to survive the 82 air raids recorded by the 3rd Defense Battalion between the start of the campaign and Nov. 15.
Air tactics were critical since the Wildcat was inferior in many regards to the Zero and the experience level of the Marine fighter pilots was low in many cases. Major Smith, commander of VMF-223, devised tactics that he taught to his pilots and that exploited the strengths of the Wildcat. Smith’s preferred method of attack was to get to a point ahead of the bombers with a 5,000-foot height advantage. Once this position had been gained, which was not easy given the Wildcat’s slight speed advantage over the Betty, Smith preached a diving attack concentrating on the trail aircraft in the formation. The desired firing range was 1,000 feet in a right-to-left diving attack across the bomber formation. This tactic had many key advantages. It used the Wildcat’s superior diving speed to get past any escorting Zeros, it evaded most of the Betty’s defensive armament, the Japanese formation could not evade it, and it presented a good shot on the Betty’s vulnerable wing fuel tanks. After the initial attack, the Wildcats were told to pull out of the dive into a climbing left turn and then reassess. If the Zero escort had not intervened, Smith taught that the Wildcats should make another pass at the bombers. The primary mission of the interception was to break up the bomber formation. Obviously, the Zeros were not going to let the Wildcats attack the bombers without intervening, so when they did make an appearance Smith told his pilots not to get into a dogfight with the extremely maneuverable Zeros. The smart play was to use the Wildcat’s superior diving speed to clear the area or seek safety in a cloud.
On Oct. 23, the commander of Cactus Air Force’s fighters, Lt. Col. Harold Bauer, ordered a change in tactics. He discerned that the quality of Zero pilots had declined, and he was sure that the Wildcat pilots were now better. Accordingly, he ordered his pilots on the Oct. 23 interception to dogfight with the Zeros whenever the opportunity arose. The results on that day seemed to justify his assessment.
If the Marine pilots were shot down, even over Japanese lines, there was a good chance they would reach the Marine perimeter and return to duty. This was due to the brave efforts of the coast watchers and loyal local people on the island. More than half of the pilots shot down over or near Guadalcanal returned to fight again.
The Dauntless crews were just as important for the successful outcome of the campaign as were the Wildcat pilots. Each Dauntless carried two crewmen, the pilot, and the rear gunner. In addition to the Marine dive-bomber squadrons on the island, there was a constant rotation of Navy dive-bombers operating from Henderson Field. The Dauntless had a short combat radius when loaded with 1,000lb bombs. In the morning and afternoon, Dauntlesses were sent into the area known as the “Slot” (the passage between the central Solomon Islands leading to Guadalcanal) to scout for Japanese ships. The most common Japanese ships encountered were destroyers conducting transport missions down the Slot. If these ventured too close to Guadalcanal in the afternoon or were late leaving the waters off the island at night and had not steamed out of range by morning, they were liable to be attacked. Dive-bombing was an accurate method of attack when conducted by a trained crew but hitting a ship as fast and maneuverable as a destroyer was difficult for any dive-bomber pilot. If possible, the pilot would line up his attack along the ship’s length to provide a larger target, but hits were rare on destroyers. At night, the Tokyo Express unloaded its cargo of troops and supplies only miles from Henderson Field. The Dauntless pilots were tempted to try night attacks. These were dangerous since they were operating from an unlit airfield. They were also ineffective since the Japanese destroyer captains learned to stay concealed in the darkness by not firing on the dive-bombers and keeping their speed down to reduce their wake.
Guadalcanal 1942-43 is published by Osprey Publishing and is available to order here.