This offline application enables pilots to determine their night flight time. All you need to do is just to set the place and time of departure and arrival. The app uses algorithm to determine orthogonal distance and algorithm to determine sunrise or sunset. The definition of night can be modified in Settings according to users national regulations. The Vincenty formula is used for calculation of distance. To calculate sunrise/sunset the Sunrise equation is used. The app contains the default database. The source of data for it is openflights.org database. If the airport you need is missing you can create it in users database.