أرسل هذا في رسالة قصيرة: Preliminary ground risk tiering for small unmanned aerial vehicles (sUAV) in metropolitan environments

 _    _    _    _     _____    __   __     _____  
| || | || | || | ||  |__  //   \ \\/ //   / ___// 
| || | || | || | ||    / //     \ ` //    \___ \\ 
| \\_/ || | \\_/ ||   / //__     | ||     /    // 
 \____//   \____//   /_____||    |_||    /____//  
  `---`     `---`    `-----`     `-`'   `-----`