I'd guess Japanese artillery was raining down on the air field. It was on the "Canal of course, along with Japanese battleships coming in at night. I am still shocked that battleships could not put an airfield out of operation for days. They cruised the straits with impunity and rained down shells most of the night. Henderson Field was mostly up and running the next morning despite losing some planes. Those IJN BBs should have been able to demolish the air strip with their 14 inch guns.
The Seabees don't get their due. Take out Henderson Field and this battle probably is a major US defeat.