These small airplanes were called Cessna Caravan 208 operated by Susi Air. They fly between small airports in Kebar, Sausapor, Numfor, Wasior, and Bintuni and big airports in Manokwari, Sorong, Jayapura and Merauke. Susi Air also serve a lot of remote airstrips in other parts of Indonesia. Cessna Caravan 208 can carry 12 passengers.
I used to fly between Numfor island and Manokwari city by this aircraft, first with 2 Finish tourists and then with 4 Czech tourists. I also used to fly with 2 Dutch tourists between Merauke city and District Senggo in southern region of West Papua. Although the airplane was very small, it was quite comfortable to fly with. The plane could take off and land on short runways.