Read the NTSB report. Compare the FDR vs the CVR. Captain Denny King (RIP) walked into the cockpit several minutes after the event started. He saw the yokes full back and full right. Immediately looked at the hydraulics gauges and realized they had no hydraulics. That is when control of the a/c improved as CA King assumed controls of the thrust levers. CA Haynes, and crew, tried throughout the event to use systems that required hydraulics (a/p, slats). CA King kept having to correct them. It's in the CVR transcripts. It's also part of CA King's refusal to close the throttles. BTW, he'd basically sacrificed himself by squatting by the center console and he flew into the crash without a seatbelt. He's the hero.