September, the Japanese raided Guadalcanal a total of ten times, losing 31 aircraft destroyed and seven more heavily damaged, primarily due to the defensive efforts of CAF fighter planes. Most of the Japanese aircrewmen in the destroyed aircraft were killed. During this same time, the CAF Marine Corps fighter squadrons lost 27 aircraft with nine pilots killed. On 12 September 25 Bettys and 15 Zeros from Rabaul raided Henderson Field. Alerted by the coastwatcher Donald Kennedy, and by the radar at Henderson Field, 20 Wildcat fighters from the Marine and Navy fighter squadrons took off to intercept this raid. In the resulting battle, two Betty bombers were shot down by Marine anti-aircraft fire, and four Bettys and one fighter were shot down by the Wildcats. One U.S. Navy pilot died attempting to land his damaged fighter back at Henderson Field following the action. That night the field was shelled by the Japanese cruiser Sendai and three destroyers in support of the Japanese Army attacks on the Lunga perimeter – the first night of the Battle of Edson's Ridge. This shelling killed two pilots from VMSB-232 and one pilot from VMSB-231, but it did not damage any aircraft or the airfield. On 13 September 18 Wildcats arrived at Henderson Field from the carriers USS Hornet and USS Wasp. The morning of this same day, Tsukahara sent a reconnaissance mission of two Type 2 aircraft escorted by nine Zeros to find out if the Japanese Army had captured Henderson Field during the night. The Zeros tangled with Cactus Air Force fighters from VMF-223, VMF-224, and VF-5, losing four Zeros along with their pilots. The CAF lost four fighters, two in combat and two to accidents with two CAF pilots killed. An afternoon raid the same day by 27 Bettys and 12 Zeros attacked Henderson Field at 14:00 and again resulted in intense clashes with the Cactus defenders. In the skirmish, two Betty bombers were lost and two were heavily damaged, with three crewmen killed and six captured. Two Wildcats were lost, one each from VMF-212 and VF-5, with both pilots killed. On that same day, two R Area floatplane Zeros from Rekata Bay swept over Lunga Point and shot down a scoutplane SBD from VMSB-231, killing both of its crewmen. Another CAF scout SBD from VS-3 ditched in the ocean that afternoon during their search patrol, and both crewmen were lost. Later