Human Factors

Human Factors Part 1: Read and make reference to the incident " Hevilift DHC6 near Port Moresby on Sep 20th 2014, impact with terrain" using information in human factors SCHELL model. Which SCHELL components do you think have led to this occurrence. How can such incidence be avoided in the future? Part 2 : Same as part 1 but on different incident " PIA B773 at New York on Sep 8th 2015, gear did not retract.