RE: How high is a mistake?
It depends on the plane - With my Sig Somethin' Extra (OS FS70II 13x6 APC) I would come down to 12ft. inverted flying slowly above the field with the engine purring around idle; With the GP Super Sportster (OS 46FS 11x6 K-Series MA) that would be 20+ft. at at least 1/2 throttle.