For several minutes before the end of the data stream, the airplane experienced continuous moderate turbulence, with G forces ranging from .77 to 1.5. About a minute before the end, it began a turn to the right with about 30 degrees of bank and a rate of descent of 600 to 900 fpm. After it had descended 500 feet, its bank angle rapidly increased past wings-vertical, the rate of descent soared to 11,500 fpm, and the airspeed rose from 150 to 280 knots. Fuel flow and engine rpm, meanwhile, remained steady at cruise settings; the pilot evidently made no effort to slow the airplane by reducing power or flattening the propeller pitch. The G-load stayed at an almost neutral 1.1 G until six seconds before the end, at which point it rose rapidly to 4.8 G. At the last data point, the airplane was at 6,135 feet and 290 knots, pointed straight down. Bank angle has no meaning in a vertical dive, but the imperturbable digital historian nevertheless recorded it as 113 degrees. Noting the rapid increase in G-force during the final seconds, the NTSB, assuming that it coincided with the airplane's emergence from the bottom of the cloud deck, observed that "the sudden onset of G-load is [consistent] with the pilot's attempt to recover from the rapid descent and unusual attitude."