In what way is the escape of Huck from his father and Jim from slavery similarly ironic to Tom's elaborate release of Jim from his imprisonment? Was the voyage necessary for Huck or Jim? In what ways was it necessary for their growth as characters?

I suppose both escapes are ironic in that they run contrary to Southern social norms. Despite Pap being a useless abusive drunk, it was generally believed that Huck belonged with his father. It was also believed that Jim belonged a slave rather than a father to his family. I think that Huck more than Jim needed this voyage to mature in the way he did. Huck was able to see first hand that a black person could be his brother. Ironically Jim was released long ago but his time with Huck might have been his one experience with a white person he did not regret.