If the safety steward had waived the red flag or held in in a way so it would be visible to drivers as opposed to letting the flag hang, this accident would have been easily avoided. That said, driving schools (at least the ones that are well run) always teach drivers to stop off the race line under a red flag to avoid the possibility of someone coming in from behind at high speed and ramming into you. Hopefully there were lessons learned for safety stewards and HPDE students here.
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