Yes last year was when that bad crash happend. The NTSB report was released about 3 weeks before the races started. Basically what happend was poor maintenance practice's. There were mounting hardware that needed to be replaced that didnt get replaced on the horizontal flying surfaces. Roughly $10 in nuts bolts and screws. But the main contributing factor was that the aircraft wasnt properly test flown. It was test flown and deamed airworthy. However it was never tested at the speeds and G loading that it was to experience while flying at race speeds (500+mph). So that coupled with the more or less $10 in hardware that should have been replaced when noted ended in a huge crash with needless loss of life and injuries.
Its a shame because the mechanics that worked on that aircraft I held in high reguard. And the pilot was a very dear friend to many including myself.