повна відсутність хмарності, чисте небо
operational ceiling (service ceiling)
static ceiling (the highest altitude at which the helicopter is capable of hovering in standard atmosphere) / hover ceiling
unlimited visibility
absolute ceiling (AC)
ceiling (aeronautics)
service ceiling
ceiling lining
ceiling
ceiling altitude
zero ceiling
hover ceiling
static ceiling
low ceiling
minimum ceiling
operating ceiling
smoke ceiling
ceiling in rank
ceiling height
manpower ceiling