MILPERSMAN 1754-030, Chapter 15, Support of Family Members, provides a guide for family support in the absence of an agreement or court order.  Para. 4.a.  The obligation is expressed as a fraction of the sailor's "gross pay" (defined as base pay plus BAH, if entitled, but excludes all other allowances, such as BAS, hostile fire pay, etc).

• Spouse only: 1/3
• Spouse & 1 minor child: 1/2
• Spouse & 2 or more children: 3/5
• 1 minor child: 1/6
• 2 minor children: 1/4
• 3 minor children: 1/3

Waiver of Obligation

Only the Director, Dependency Claims, Navy Military Pay Operations, at DFAS, may grant a waiver.  Pursuant to para. 5.b, the grounds for a waiver are:

• Desertion without cause,
• Physical abuse, or
• Infidelity by the spouse.

Should a waiver be granted, it only applies to the spousal portion, and not the portion attributable to children.