What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
Right wing folded during aerobatics. Homebuilt not modifier for aerobatic flight per beefing up spar. (.4) a witness said the pilot was performing aerobatics, and while maneuvering, the aircraft (acft) went into a nose high attitude as if it was coming to the top of a loop. He said one of the wings suddenly 'folded' up, and 'it looked as if it had bent at the connection between the wing and the fuselage. . . .' The acft then entered an uncontrolled descent & crashed. Metallurgical exam of the right wing revealed overload fractures in the lower & upper main spar caps, which were indicative of upward failure; initial fracture was in the lower cap area. Twisting & upward bending of the main upper spar cap was noted, as well as 'overstress separation.' Five bolt holes were found at the inboard portion of the upper & 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, but circular markings were noted on the forward side of both outboard holes, & similar indications were noted on the aft side of 2 other holes in the lower main spar cap. The investigation did not determine whether the missing bolts had failed & separated during the breakup, or if they had not been reinstalled during previous maintenanc e/modification. All rivets in foth the upper & lower main spar caps were broken through the shanks' consistent with direct shear separations. No evidnece of cracking or breaking of rivet heads...was noted.' This was 1 of 3 RV-3S built by tony duci & the 2nd ot structurally fail in flight. Acft had been modified as an RV-3A, but had not been re-certified as such. Aerobatic gross weight limit (1050LBS) had been exceeded by an estimated 120 lbs.
As the FAA filed it
RIGHT WING FOLDED DURING AEROBATICS. HOMEBUILT NOT MODIFIER FOR AEROBATIC FLIGHT PER BEEFING UP SPAR. (.4) A WITNESS SAID THE PILOT WAS PERFORMING AEROBATICS, AND WHILE MANEUVERING, THE AIRCRAFT (ACFT) WENT INTO A NOSE HIGH ATTITUDE AS IF IT WAS COMING TO THE TOP OF A LOOP. HE SAID ONE OF THE WINGS SUDDENLY 'FOLDED' UP, AND 'IT LOOKED AS IF IT HAD BENT AT THE CONNECTION BETWEEN THE WING AND THE FUSELAGE. . . .' THE ACFT THEN ENTERED AN UNCONTROLLED DESCENT & CRASHED. METALLURGICAL EXAM OF THE RIGHT WING REVEALED OVERLOAD FRACTURES IN THE LOWER & UPPER MAIN SPAR CAPS, WHICH WERE INDICATIVE OF UPWARD FAILURE; INITIAL FRACTURE WAS IN THE LOWER CAP AREA. TWISTING & UPWARD BENDING OF THE MAIN UPPER SPAR CAP WAS NOTED, AS WELL AS 'OVERSTRESS SEPARATION.' FIVE BOLT HOLES WERE FOUND AT THE INBOARD PORTION OF THE UPPER & 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, BUT CIRCULAR MARKINGS WERE NOTED ON THE FORWARD SIDE OF BOTH OUTBOARD HOLES, & SIMILAR INDICATIONS WERE NOTED ON THE AFT SIDE OF 2 OTHER HOLES IN THE LOWER MAIN SPAR CAP. THE INVESTIGATION DID NOT DETERMINE WHETHER THE MISSING BOLTS HAD FAILED & SEPARATED DURING THE BREAKUP, OR IF THEY HAD NOT BEEN REINSTALLED DURING PREVIOUS MAINTENANC E/MODIFICATION. ALL RIVETS IN FOTH THE UPPER & LOWER MAIN SPAR CAPS WERE BROKEN THROUGH THE SHANKS' CONSISTENT WITH DIRECT SHEAR SEPARATIONS. NO EVIDNECE OF CRACKING OR BREAKING OF RIVET HEADS...WAS NOTED.' THIS WAS 1 OF 3 RV-3S BUILT BY TONY DUCI & THE 2ND OT STRUCTURALLY FAIL IN FLIGHT. ACFT HAD BEEN MODIFIED AS AN RV-3A, BUT HAD NOT BEEN RE-CERTIFIED AS SUCH. AEROBATIC GROSS WEIGHT LIMIT (1050LBS) HAD BEEN EXCEEDED BY AN ESTIMATED 120 LBS.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.