Livro infantil sobre criança na geração de estrelas falida salva por Cygnus The Swan?

Possivelmente Os Vigilantes do Espaço ?

A descrição:

The starship Genesis carries the last survivors of Earth on a desperate flight to a new home. But the ship is slowly disintegrating and the oxygen supply is running out -- it's a race against time and space. Out of the far reaches of the universe the Watchers of Space gather: Orion, the giant golden man; Starnight, the sword of power and magic; and Cygnus, the beautiful swan. Together they will help save the doomed ship. But no one on the Genesis will believe twelve-year-old William when he tells them of the Watchers' plan. For they no longer believe in anything -- not till they see William go spinning off into space...

A descrição parece se encaixar, mas acho que foi publicada em 85, portanto, um pouco mais tarde do que você especificou: (

Poderia ser a série Swan com capuz ?

link

When the girl is later kidnapped by her own kind and taken to the Anacaona's home world, the Hooded Swan is sent to retrieve her. They fly to Chao Phrya, a world settled by a human generation ship, the Zodiac, whose descendants now believe it is their promised land, despite the presence of the Anacaona.

The kidnappers manage to land illegally in the jungle before Charlot can get permission from the uncooperative locals, who eventually agree to let the Hooded Swan land. Charlot chooses Grainger and Eve to join the local search party, which consists of two humans, Max and Linda, and three Anacaona, Danel, Michael, and Merce. As they travel, Grainger discovers that the Anacaona have minds adaptable to an almost absurd degree, and create completely human personalities simply to interact with humans.

Não tem um cisne falante, mas a ideia de Cygnus, o cisne, e os navios geracionais estão presentes. Assim como uma criança que está em perigo.