The P-38 was powered by two well broken in O.S. 91 four strokes. Both engines were running and he was trying to trim the airplane when the snaps occured. He said that the plane snapped right and he was able to recover it but then it immediately snapped left and went in. As one observer put it, the airplane started out the flight moving like a scalded cat. After three trips across the field, the pilot slowed it to make it easier to concentrate on trimming it. When he reached the end of the field, he had to turn again and that is when it snapped. The pilot told me that he thought that he might have had too much elevator authority. It's also possible that the CG was too far aft, but that's my speculation, not the pilot's. It is also possible that something broke on the airplane, but there was so much damage on impact that making that determination was impossible. A highly tapered, highly loaded wing is just very prone to snapping and pilots need to be aware of this. When you set up your aileron throws, it will help a lot if you put in a lot of differential. Also be careful of your CG location.