This is a crazy failure, but the chute did its job.

August 17, 2010 — An incredible video that’s gone viral on YouTube shows a wing collapsing on a RANS S-9 Chaos during an air show performance in the city of El Trébol, Santa Fe province, Argentina, this past Sunday, August 15. Seconds after the wing breaks away, pilot Dino Moline was able to immediately and successfully deploy the airplane’s Ballistic Recovery Systems (BRS) parachute, and the aircraft floated safely to the ground with Moline emerging uninjured.
On several blogs, the consensus was that the pilot exceeded the aircraft’s G limit in the negative-G maneuver, causing the wing to buckle and fall off the airframe.
That seems to be confirmed according to information received through EAA Chapter 1339, Parana River, Argentina, from César Falistocco, lead member of the Rans Team, who wrote (translated from Spanish):
“In this particular case, and until we get to do special tests on (the aircraft) that show otherwise, we assume, with a confidence of 99%, (the maneuver) exceeded the maximum load of G that supports the wing, and therefore collapsed studs inward (buckling), both at the same time and exactly in the middle.
Randy Schlitter, RANS founder, said that the accident appears to have been caused by a combination of the airplane being over gross weight and too much speed. “We don’t know too much about it other than it had a Rotax 912 and a parachute,” he said. “It was going too fast and pushing too many negative Gs.” The aircraft was designed in two engine configurations, the 47-hp Rotax 503 and the 65-hp Rotax 582.
Regarding the fire and smoke appearing in the video after the aircraft came to rest, Falistocco wrote, “The left wing was carrying the fuel tank,” and hoses sprayed fuel, “starting a small fire in the cabin and a larger fire in the corn stubble.”
“The pilot, however, was out of the cabin, and the fire consumed the entire aircraft. There was no blow to hit the ground at the low rate of descent of the parachute, but the plane was dragged…80 meters on the ground, since there were strong winds. Upon leaving, the pilot (was) also dragged and scraped against the ground.”
http://www.eaa.org/news/2010/2010-08-17_BRS-WingSeparate.asp See this crazy video here:
http://www.youtube.com/watch?v=XnHuIET4P2s&feature=player_embedded