213 § 3689. Assignments and allotments of pay (a) Under regulations prescribed by the Secretary of the Army, a commissioned officer of the Army may transfer or assign his pay account, when due and payable. (b) A contract surgeon or contract dental surgeon, on duty in Alaska, Hawaii, the Philippine Islands, or Puerto Rico, may transfer or assign his pay account, when due and payable, under the regulations prescribed under subsection (a). (c) No assignment of pay by an enlisted member of the Army is valid. (d) The Secretary may allow any— (1) member of the Army; (2) contract surgeon; or (3) permanent civilian employee of the Department of the Army on duty outside the United States; to make allotments from his pay for the support of any of his relatives, or for any other purpose that the Secretary considers proper. If an allotment made under this subsection is paid to the allottee before the disbursing officer receives a notice of discontinuance from the officer required by regulation to furnish the notice, the amount of the allotment shall be credited to the disbursing officer. If an allotment is erroneously paid because the officer required by regulation to so report failed to report the death of the allotter or any other fact that makes the allotment not payable, the amount of the payment not recovered from the allottee shall, if practicable, be collected by the Chief of Finance from the officer who failed to make the report. § 3690. Exemption from arrest for debt: enlisted members No enlisted member of the Army, while on active duty, may be arrested on mesne process or taken or charged in execution for any debt, unless it was contracted before his enlistment and amounted to at least $20 when first contracted. § 3691. Flying officer rating: qualifications Only officers of the Army in the following categories may be rated as flying officers: (1) Officers who have aeronautical ratings as pilots of service types of aircraft or as aircraft observers. (2) Fligl^t surgeons. (3) Officers undergoing flight training. (4) Officers who are members of combat crews, other than pilots of service types of aircraft, aircraft observers, and observers. (6) I n time of war, officers who have aeronautical ratings as observers. § 3692. Pilot rating in time of peace: qualifications To be eligible to receive a rating as a pilot in time of peace, a member of the Army must pilot a heavier-than-air craft for at least 200 hours, of which 75 are alone, and must successfully complete the prescribed course.