19981010028769A

Witnesses stated that the acft appeared to be performing aerobatic maneuvers and had completed a loop when it stalled, spun in, and crashed. (-23) aircraft observed doing aerobatics at low altitude. Aircraft commenced a loop. At the bottom of which aircraft entered a partial spin until ground impact. Aircraft fell straight down through grove of trees.(.19) on October 10, 1998, at 1711 eastern daylight time, a xray 78 inc, RV-4, N741WB, collided with the ground near Apopka, Florida. The personal flight operated under the provisions of title 14 CFR part 91 with no flight plan filed. A review of weather data from the nearest reporting facility disclosed that, visual weather conditions prevailed at the time of the accident. Examination of the airplane at the accident site revealed that the airplane had sustained substantial damage. The private rated pilot and passenger were fatally injured. The flights' exact departure time from Apopka, Florida, was not determined. Witnesses located in the immediate vicinity of the accident site reported that, they observed the airplane as it entered a loop type maneuver. They also reported that as the airplane entered the bottom of the maneuv er, there was some erratic flight control movement followed by a nose low collision with the ground. (.4)witnesses located in the immediate vicinity of the accident site observed the airplane as it entered a loop type maneuver at a low altitude. As the airplane entered the bottom of the maneuver, proper airspeed was not maintained, the airplane became erratic, and collided with the ground in a nose low attitude. According to witnesses, the engine continued to operate throughout the maneuver. The fuel selector was found in the on position, and the fuel tanks appeared to be ruptured from impact. Examination of the airframe and engine failed to disclose a mechanial problem with the airplane. The toxicology examinations performed on the pilot were negative for carbon monoxide, cyanide, ethanol, and drugs.