(Creative Commons photo by Matt’ Johnson)Wreckage of a plane that went down Friday afternoon 18 miles west of Juneau was being picked up Sunday for further investigation by the National Transportation Safety Board.Download AudioWings of Alaska flight 202 from Juneau to Hoonah crashed into a mountain north of Point Howard on the mainland, killing the pilot. The Cessna 207 was carrying four passengers who survived the crash.The purpose of the National Transportation Safety Board is to perform an in-depth investigation to determine probable cause of the crash. Clint Johnson, chief of the Alaska Regional Office in Anchorage, describes it as a process of elimination.“We look at three main areas when we get on an accident site – man, machine, environment. Man being the human performance portion, machine being the mechanical and the environment is obviously the weather. So right now, none of those three areas have been discounted at this point,” Johnson says.NTSB investigator Chris Shaver spent Saturday at the crash site, which is steep and tree-covered.Johnson says the investigative team for the wreckage includes representatives from the airframe manufacturer, Cessna Aircraft Co., and the engine manufacturer, Continental Motors. That process takes a few days.Johnson says Shaver is also working closely with Wings of Alaska.“That is a part of the investigation. Chris will probably be in town for the next 2 to 3 days, if not longer than that, conducting a number of interviews as far as management personnel, other pilots that knew this pilot, dispatch personnel, there’s a host of people,” Johnson says.Wings flight 202 departed Juneau on Friday around 1 p.m. for what was supposed to be an 18-minute flight to Hoonah. The Juneau Police Department received a 911 call from someone on the plane around 1:20 reporting the crash.The pilot was 45-year-old Fariah Peterson of Birmingham, Alabama. Her body was recovered Saturday afternoon and will be sent to the State Medical Examiner Office for an autopsy.The four surviving passengers are 64-year-old Ernestine Hanlon-Abel of Hoonah, 57-year-old Humberto Hernandez-Aponte and wife 60-year-old Sandra Herrera Lopez of Juneau, and 15-year-old Jose Vazquez of Puerto Rico. They were all initially brought to Bartlett Regional Hospital in Juneau. Hanlon-Abel and Herrera Lopez were medevaced to Harborview Medical Center in Seattle. As of Sunday afternoon, both were in serious condition in the intensive care unit.The weather near Point Howard Friday afternoon was similar to the weather in Juneau – low clouds, light rain and patchy fog, according to a meteorologist at the National Weather Service.Wings of Alaska cancelled all flights on Saturday, the day after the crash. Service resumed on Sunday.Johnson says a full NTSB investigation takes 9 months to a year. He says a preliminary accident report will come out sometime this week.