IIRC the FO (copilot) of the Ethiopian Air flight correctly identified MCAS as the source of the problem, but was struggling to trim the airplane manually becau

IIRC the FO (copilot) of the Ethiopian Air flight correctly identified MCAS as the source of the problem, but was struggling to trim the airplane manually because it was so far out of trim that the load on the horizontal stabilizer jackscrew made it difficult or impossible for him to adjust. This possibility was mentioned in the AFM, but the recommended response - pitch nose-down to decrease the load - was not feasible in the situation.