Witness Observation
A witness reported that the aircraft was performing aerobatic maneuvers. During a maneuver, the aircraft entered a nose-high attitude, as if approaching the top of a loop. The witness then observed one wing suddenly fold upward, describing it as bending at the connection between the wing and the fuselage. The aircraft subsequently entered an uncontrolled descent and crashed.
Examination Findings
Metallurgical examination of the right wing revealed overload fractures in both the lower and upper main spar caps. The fractures were indicative of upward failure, with the initial fracture occurring in the lower cap area. Twisting and upward bending of the main upper spar cap were noted, along with evidence of overstress separation. All rivets in both the upper and lower main spar caps were broken through the shanks, consistent with direct shear separations. No evidence of cracking or breaking of rivet heads was found.
Missing Bolts
Five bolt holes were found at the inboard portion of the upper and lower main spar caps with no respective bolts or remnants of such bolts. No deformation or distortion of any of the bolt holes was noted. Circular markings were observed on the forward side of the two outboard holes, and similar indications were noted on the aft side of two other holes in the lower main spar cap.
The investigation did not determine whether the missing bolts had failed and separated during the breakup, or if they had not been reinstalled during previous maintenance or modification.
Aircraft Background
The aircraft was one of three RV-3s built by Tony Duci and the second of those to structurally fail in flight. It had been modified as an RV-3A but had not been re-certified as such.
Weight Exceeded
The aerobatic gross weight limit, stated as 1,050 lbs, had been exceeded by an estimated 120 lbs.