Flight Reduction (Hive Flight Cover) 15 Cm You need to keep under control and observation where your colony bees are and what they do, including entering and exiting the hives. From time to time, you may need to narrow down the flight, close the flight, or open it completely. The hive flight cover, which makes your job easier and allows you to control the hive in such cases, is made of plastic material, practical and useful.