There is actually evidence of one Belkan Aircraft carrier named "Njord".
Evidence of this ship appears in the Assault Records from Ace Combat Zero. If you shoot down the F-35 ace which appears in the Futuro canal mission, it will note that the pilot flew off the carrier Njord before being killed over the Futuro canal.
The carrier has never been seen within the games however.
The exact assault record is as follows:
Name: Hugo Parcham Callsign: Moewe Age: 29 Sex: Male Nationality: Belkan Aircraft: F-35C JSF Status: Killed in Action (04/24/95 - Operation Round Hammer)
Bio: Assigned to the Belkan Navy, he became their top ace from 1990 to 1995. During the assault on the Futuro Canal, he was given the duty of intercepting Galm Flight. During the conflict, he managed to take off from the aircraft carrier Njord, but was later shot down.