Slightly off Course

Eric heard a loud crash and knew that the airplane he was on had just crashed on an island. When he looked around, he realized that the majority of the passengers had died from the severe impact. Once he left the plane he discovered there were seven survivors. He also discovered that the front of the plane was smashed in. Sending a message wasnt going to work. How could they reach someone to let them know where they landed? How would they survive if they couldnt contact anyone? When would they be rescued?