Aircraft Carrier
noun
An aviation (航空) mother warship is a warship that is like mother to all the aviation things (the airplanes). They come home to their mother warship, which is an aircraft carrier.
こうくうぼかん
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
その航空母艦は突然視界から消えたんです。
The aircraft carrier suddenly disappeared out my field of vision.