i don't believe that you can just give your mother full physical custody with a father being involved. He has to have a chance to have custody if you are being deployed. Unless you can prove him unfit. I am sure that this is not what you want to hear.
But yes he will have to sign something, and unless he is a complete loser.....not saying that he is......but he would have the right to take over the custody, being that he is the father.......
I hope this helps if you have anymore questions about this just email me. Ill be glad to help...
Here is information I obtained from a solicitor's website:
Divorce in England & Wales is currently granted on the basis of the irretrievable breakdown of marriage. The Family Law Act 1996 which was passed by Parliament would have amended the law in quite significant ways but it now appears that many of its provisions may never be brought into effect. There are currently five so-called "grounds" which can be relied upon as evidence of irretrievable breakdown:
2. Unreasonable behaviour
4. Two years' separation with consent
5. Five years' separation without consent
There is additional information on his website.