The pilot reported that he was conducting a non-commercial personal flight when during the climb and passing through 4,000 ft, the airplane experienced wind shear causing the airplane to lose 1,500 ft. of altitude. The pilot recovered the airplane from the altitude loss, continued to the destination airport, and landed without further incident. The airplane sustained substantial damage to both wings, which were deformed upwards. The right front seat passenger reported that he was charged money for the flight, which was transportation to and from a fishing lodge. He reported that the airplane was in the clouds at the time it lost control and that as the airplane came out of the clouds, the pilot was pulling away from the ground, and was “pulling hard.” The pilot then got the airplane “upright.” The airplane was heading “almost directly” and “straight” at the ground before it was recovered. The passenger then asked the pilot what happened after the airplane was leveled off, and the pilot told him that he thought the autopilot had failed. The passenger reported the autopilot was not on, and it “seemed” that the pilot was not “paying attention to the instruments.” There were no warning tones or audible annunciations when the loss of control occurred. The passenger reported that they had just “barely taken off,” and did not feel any turbulence prior to the loss of control. He further added that “there was nothing before they got out of the clouds.” Pilot reports over the region mainly reported low overcast cloud cover, with no reports of significant turbulence or low-level wind shear. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation.