On 7 August 1942, Major General Alexander A. Vandegrift’s 1st Marine Division stormed ashore on the Japanese-held islands of Guadalcanal and Tulagi in the Solomon Islands. The operation, code-named Watchtower, was the first major U.S. offensive of World War II in the Pacific and designed to thwart the Japanese threat to Allied supply and communication routes between the United States, Australia, and New Zealand.
By nightfall on D+1, the 1st Battalion, 5th Marines had overrun one of the division’s major objectives—the nearly finished Japanese airfield on Guadalcanal. Once completed, the renamed Henderson Field would be the focus of the long struggle for Guadalcanal. A hodgepodge collection of Marine, Navy, and Army aircraft and aviators nicknamed the “Cactus Air Force” would defend the airfield against relentless attacks by Japanese bombers, while Marine infantrymen and Raiders, supported by GIs, would turn back Japanese ground offensives intended to capture it.
Finishing the Field
The 1st Marine Division engineer officer surveyed the captured airstrip and estimated that his men could make 2,600 feet of the strip ready in two days and the remaining 1,178 feet operational in two weeks. However, he made the forecast before learning that Rear Admiral Richmond Kelly Turner’s transport ships carrying the airfield construction equipment would withdraw before all but a fraction of their contents could be unloaded. Most of the earth-moving equipment—bulldozers, power shovels, and dump trucks—arrived off Guadalcanal in the USS Fomalhaut (AK-22), but only an estimated 15 percent of her contents made it ashore before the transports departed.1
The Navy’s decision to withdraw the transports with equipment and Marines still on board left Vandegrift in a distressing position. It was made worse by the fact that Vice Admiral Frank Jack Fletcher also had withdrawn his aircraft carriers, which provided critical air support. Under these conditions, the airfield assumed even greater importance, becoming the center of the division’s defense and its lifeline.
The 1st Engineer Battalion, augmented by the 1st Pioneer Battalion, began the backbreaking work of completing the airfield using captured equipment, much of which was in poor mechanical condition. The engineers had to move some 5,000 cubic yards of soil because the Japanese had started construction from both ends of the strip, leaving a gap of 180 to 200 feet in the middle. The Marines used hand tools and Japanese dump trucks to fill the incomplete center of the runway, a Japanese road roller to flatten the fill after it had been spread, and a steel girder to drag the field to smooth it out. Also, several acres of banyan trees at the end of the runway had to be cleared for a flight path.
On 12 August, Vandegrift declared, “Airfield Guadalcanal ready for fighters and dive bombers.” However, it still lacked taxiways, revetments, and drainage, which was a major problem because of the daily rainstorms. After a PBY-5A Catalina patrol bomber made the first landing, the pilot announced the field to be in excellent shape and suitable for fighter operations. Vandegrift thought it was “a particularly courageous and optimistic decision in view of the day and night air attacks and . . . surface bombardment by destroyers.”2
The field was named after Major Lofton R. Henderson, killed in action at the Battle of Midway while leading Marine Scout Bombing Squadron (VMSB) 241. Major Kenneth Weir, the division air officer, was instrumental in naming the field. “I had to do it,” he said, “or they would have named it after some potbellied old SOB behind a desk” in Washington.3
Help on the Way
Near dusk on 15 August, four elderly destroyer transports stood into Lunga Roads with aviation fuel and lubricants, bombs, ammunition, and five officers and 118 Navy enlisted men from Navy Construction Unit Base 1 (CUB-1) to establish an advance fuel and supply base. Most of the sailors were recent graduates of various technical schools and had very little military training. CUB-1 shipped out so quickly they didn’t have time to load their equipment. “We had four master tool boxes. Period! That was all we had to work with,” one sailor griped. Despite the lack of equipment, “The Cub Unit people did a magnificent job,” Lieutenant Colonel Richard Mangrum, commanding officer of VMSB-232, reported.4 The sailors assisted the Marine engineers in working on the runway and also installing and manning the air-raid warning system in the “Pagoda.”
The Pagoda, a crude Japanese-built one-story structure, served as both the control tower and air operations center (Air Ops). It was located on a rise, known as Pagoda Hill or “the bull’s-eye,” about 200 yards northwest of the airstrip. “You could see it 40 miles away,” Major Albert D. Cooley, commanding officer of Marine Air Group (MAG) 14, remarked.5 The building became a target for Japanese bombing raids and later was demolished. According to Brigadier General Louis E. Woods, who served as chief of staff and then as commander of the Cactus Air Force, “Living in a pagoda on top of a hill, right in the middle of the flying field was probably . . . very stupid.”6
Initially, a captured siren was installed in the tower as an air-raid alert, but its wail often mingled with the sound of falling bombs, so it was augmented by a flag system. A black flag on the Pagoda’s pole meant “Condition Red”—enemy planes were within two minutes of the field or overhead. The alert pennant was a white flag—“Condition Yellow”—bombers en route. No flag meant the air-search radar or the Coast Watchers had not spotted any raiders.
'Forty Bombers Heading Yours'
To reach Guadalcanal, Japanese aerial formations were forced to overfly members of the Coast Watchers, an organization developed by the Royal Australian Navy after World War I. It established a network of military observers on the strategic islands that surrounded Australia’s northeastern coast. This intrepid band of volunteers would maintain radio stations behind Japanese lines to report incoming air raids and ship movements. By mid-1941, more than 100 coast-watching stations had been established, including three on Guadalcanal and two on Bougainville.
The Australian Navy set up a radio station on Guadalcanal to pick up coast-watcher warnings and relay them to 1st Marine Division headquarters. Their early warnings—sometimes as much as 45 minutes—gave fighters based at Henderson Field time to gain a favorable attack altitude. On 2 September, the Navy delivered an SCR-270-B air-search radar, which could detect high-altitude Japanese bomber formations out to 150 miles. The combination of radar and Coast Watchers gave the defenders a viable early-warning system. Noted historian Richard B. Frank, “Without it, Guadalcanal could not have been defended.”7
The Cactus Air Force
On the afternoon of 20 August, after almost two weeks of unhindered Japanese air and naval bombardment, the escort carrier USS Long Island (ACV-1) arrived with reinforcements: 19 F4F Wildcat fighters of Marine Fighting Squadron (VMF) 223, led by Major John L. Smith, and Lieutenant Colonel Mangrum’s 12 SBD Dauntless scout–dive bombers of VMSB-232. “We were launched 200 miles off Guadalcanal in the middle of the afternoon to avoid the daily air raid and landed late in the afternoon,” Mangrum related.8 The Marine Wildcats and Dauntlesses were the first planes in the Cactus Air Force, so-named because Cactus was the U.S. code name for Guadalcanal.
Vandegrift was on hand to greet the Marine fliers. “I was close to tears and I was not alone when the first SBD taxied up and this handsome and dashing aviator jumped to the ground,” the general admitted. “I told him, ‘Thank God you have come.’”9 Mangrum was surprised by the reception. “The division had been 13 days with no protection from enemy aircraft or means to intercept enemy ships. So to put it mildly, they were glad to see us.”10 Lieutenant Herbert L. Merillat, the public relations officer at 1st Marine Division headquarters, reported, “A shout of relief and welcome went up from every Marine on the island.”11
The Marine airmen soon learned that around noon nearly every day was “Tojo Time.” The 67th Fighter Squadron’s historian noted, “Flights of 20 to 40 Mitsubishi G4M ‘Betty’ bombers, escorted by fighters, would fly in at 20,000 feet (6,100 m) in perfect ‘Vee’ formations to bomb Henderson Field.”12 The regularity of the daily raids, between 1130 and 1430, had to do with the distance the Japanese aircraft had to fly from their bases at Rabaul, New Britain, a four-hour flight that left them at the extreme limit of their range.
VMF-223 and VMSB-232 were the first echelon of Hawaii-based Marine Air Group (MAG) 23 to be deployed to Guadalcanal. The group had been selected in early July for a “special mission.” Mangrum “recalled being summoned to a conference in our group commander’s office on the 5th of July and being told that my squadron and John Smith’s would be departing for Guadalcanal 1 August.”13
The two squadrons were immediately inundated with new aircraft—VMF-223’s Brewster F2A Buffaloes were replaced by the newer Grumman F4F-4 Wildcats—and several new second lieutenants just out of the training command, as well as a sprinkling of Midway survivors. VMSB-232 traded its Douglas SBD-2s for SBD-3s, a slightly later model with self-sealing fuel tanks, and received ten newly minted pilots, most of whom had never dropped a bomb.
Mangrum reviewed the new pilots’ logbooks and was appalled to discover that none of them had “much more than 200 hours in the air (compared to 800 hours for the Japanese pilots), and none in the aircraft we were equipped [with].”14 Given only one month to whip the men into shape, Smith and Mangrum worked them night and day to achieve some degree of combat effectiveness. Smith concentrated on “gunnery more than anything else, which was a good thing after we found out where we were going.”15 Mangrum conducted practice bombing runs on the sunken hull of the USS Utah (AG-16) in Pearl Harbor.
Mangrum’s squadron was assigned to intercept and destroy Japanese ships that were bringing in reinforcements. After suffering severe transport ship losses, the Japanese had resorted to shuttling in troops and supplies by destroyers and barges. “We’d come down time and again and put a bomb right through a good-sized landing barge and, of course, it would blow it to hell,” Mangrum declared.16
Within 12 hours of landing, Smith’s VMF-223 flew support for the 2d Battalion, 1st Marines, then mopping up remnants of the Ichiki Detachment, which had attempted to break through U.S. lines along Alligator Creek the previous night. That afternoon, while leading a four-plane division, Smith shot down a Zero, the first of his 19 victories. “Six Zeros came on to us,” he explained. “The plane I was shooting at pulled up with his belly to me, and I shot him fairly well. . . . We later found out that this one plane crashed into the water off Savo Island.” All of Smith’s division was shot up in the brief skirmish, but the four Wildcats made it back. “After that,” Smith said, “our pilots had a great deal of confidence in the Grumman.”17
Hit and Run
Major Smith is largely credited with developing the tactics that the Cactus Air Force used against formations of Japanese bombers, typically Bettys. The bombers usually flew at 25,000 to 27,000 feet in three “V-of-V” formations composed of three nine-plane divisions. Smith trained his pilots to climb ahead of and off to one side of the bomber formation. When they were far enough ahead, the Grummans would turn sharply to a course exactly opposite the Bettys, but 5,000 feet above them, and roll over into inverted flight, then pull through into a dive. Usually it was possible to dive on the bombers at least once before the accompanying A6M Zero, or “Zeke,” fighters got into the fray. The maneuver placed the Wildcats outside the train of any of the Bettys’ guns and gave the fighter pilots excellent gunnery angles for shots at the bombers’ vulnerable fuel tanks. At the same time, the Bettys were unable to maneuver. (The bomber’s official designation was Type One Land Attack Plane, but U.S. aviators wryly called them “Type One Lighters” or “Flying Cigars” because they were prone to catching fire when hit.)
Smith trained his pilots to dive from right to left across the V; with all friendly planes going approximately in the same direction, it only was necessary for a pilot to have a little interval between his plane and the one ahead of him to avoid worries about collisions. After the first attack, the F4Fs would pull out of their dives into climbing left turns to look over the situation. If the accompanying Japanese fighters had not shown up by this time, the Grummans would make another attack. If the Zeros were in position to fight, the F4Fs would simply dive toward Henderson Field and its antiaircraft protection or fly into a nearby cloud. Because the Grumman was no match for the Zero, it was the better part of valor to avoid combat. Their mission was to go after the bombers, not to get into dogfights.
Late in the afternoon of 22 August, the Cactus Air Force was augmented by a detachment of five Army Air Forces P-400s—the export version of the Bell P-39 Airacobra—of the 67th Fighter Squadron (“The Fighting Cocks”), under Captain Dale D. Brannon. Equipped with belly tanks, and shepherded by two B-17s, the P-400s flew 640 miles from Espiritu Santo. Brannon quipped that he landed on fumes.
The Army fighter was completely outclassed by the Zero. The P-400’s ceiling was limited to 14,000 feet because it did not have equipment for the British high-pressure oxygen system with which it was fitted and therefore could not reach the high-flying Japanese bombers. On the 27th, Brannon’s detachment was augmented with nine more P-400s, giving it a total of 13 aircraft. But five days later there were only three flyable P-400s—four had been shot down and six damaged. The 67th Fighter Squadron historian bemoaned their plight: “We can’t maneuver and dogfight with the Zero—what good are we?”
The P-400 might not do well against the Japanese fighter, but it proved valuable in support of ground troops. Armed with a 20-mm cannon, two .50-caliber and four .30-caliber machine guns, and a 500-pound bomb, the aircraft was an extremely lethal weapon.
The Army detachment was joined on the 24th by 11 SBDs from the USS Enterprise (CV-6), known as Flight 300. During the 24–25 August Battle of the Eastern Solomons, the carrier had suffered damage that precluded flight operations. This would not be the last time carrier aircraft joined the Cactus Air Force; other Navy units that flew from Henderson included Scouting Squadron (VS) Three and Fighting Squadron Five from the USS Saratoga (CV-3); Torpedo Squadron Eight from the Hornet (CV-8); VS-71 from the Wasp (CV-7); and Bombing Squadron Six from the Enterprise. Major General Ross E. “Rusty” Rowell, Commanding General, Marine Aircraft Wings, Pacific, said wryly, “What saved Guadalcanal was the loss of so many carriers.”18
At the end of August, the second echelon of MAG-23’s warplanes—Wildcats from VMF-224 commanded by Major Robert E. Galer and 12 Dauntlesses from VMSB-231 under Major Leo R. Smith—joined the Cactus Air Force. The air group’s four squadrons were the first of 15 Marine squadrons that flew combat missions from Henderson Field between 21 August and 9 December 1942. On 3 September, hard-driving Brigadier General Roy S. Geiger took command of the Cactus Air Force, which he is credited with holding together during the worst days of the struggle for Guadalcanal.
The buildup of the Cactus Air Force quickly turned the air and sea clashes around the island into battles of attrition. The Japanese were hell-bent on knocking out the airfield, and the Cactus Air Force was just as determined to prevent that from happening. The daily encounters turned into a deadly routine. The Japanese launched bombing raids from Rabaul, their route taking them over islands where the Coast Watchers were stationed. Most of the time the observers’ reports would reach Cactus headquarters in time for the U.S. fighters to get airborne and reach an advantageous altitude to meet the raids.
Losses were heavy for both sides but particularly bad for the Japanese. The best estimate of their losses from 20 August through 15 November is 96 fighters, 92 Bettys, and 75 other types, mostly floatplanes.19 Cactus Air Force losses included 118 planes shot down and another 30 that were victims of operational accidents. Eighty-four Cactus pilots were killed from all causes, including 38 fighter pilots killed in aerial combat. For the Cactus Air Force, the struggle for Henderson Field was primarily over by mid-November. There would still be combat but not of the intensity of the first 88 days of the campaign.
The struggle for Guadalcanal overwhelmingly was focused on Henderson Field and the men of the Cactus Air Force. They took on Japanese air power and broke it with their courage and skill. The air arm of the Japanese Imperial Navy never recovered from the savage attrition of those few weeks in late 1942.20
1. The Guadalcanal Campaign (Washington, DC: Historical Division, Headquarters U.S. Marine Corps, 1949), 63.
2. A. A. Vandegrift, with Robert B. Asprey, Once a Marine: The Memoirs of General A.A. Vandegrift, U.S.M.C. (New York, Ballantine Books, 1966), 134.
3. LTGEN Charles H. Hayes, Oral History (Quantico, VA: Marine Corps Oral History Program, 1970), 63.
4. Robert Sherrod, History of Marine Corps Aviation in World War II (Washington, DC: Combat Forces Press, 1952), 78.
5. LTGEN Albert D. Cooley, Oral History (Quantico, VA: Marine Corps Oral History Program, 1969), 19.
6. LTGEN Louis E. Woods, Oral History (Quantico, VA: Marine Corps Oral History Program, 1968), 184.
7. Richard B. Frank, Guadalcanal: The Definitive account of the Landmark Battle (New York: Random House, 1990). 207.
8. LTGEN Richard G. Mangrum, Oral History (Quantico, VA: Marine Corps Oral History Program, 1971), 20.
9. Vandegrift, Once a Marine, 139.
10. Mangrum, Oral History, 22.
11. Herbert C. Merrilat, The Island (Boston: Houghton Mifflin, 1944), 67, cited in Sherrod, History of Marine Corps Aviation, 79.
12. Dick Camp, Leatherneck Legends: Conversations with the Marine Corps’ Old Breed (Zenith Press, 2006), 91–106.
13. Mangrum, Oral History, 15.
14. Ibid, 15.
15. Thomas G. Miller Jr., The Cactus Air Force (New York: Harper & Row, 1969), 22.
16. Mangrum, Oral History, 31.
17. Miller, Cactus Air Force, 29.
18. Sherrod, History of Marine Corps Aviation, 90.
19. Miller, Cactus Air Force, 209.
20. Ibid, 207.