Aircraft Field Loadable Software is a critical system component on an aircraft and is divided into different categories according to its control methods, approval methods and functions. The customized software is the aircraft loadable software that the airline can modify the data according to its own operation requirements. This article analyzes and studies the issues of “phone number missing” and “system not available” after the installation of satellite communication system ORT database update. Taking this as a case, the process and situation were explained in detail corresponding to the specific issues in order. Combined with the practical experience of the technical management of airline customizable field loadable software, the potential risk points in the maintenance and operation process were analyzed and studied. This paper provides ideas and suggestions for the change management and quality assurance management of customized software for airlines.