A licensed master, mate, pilot, or engineer of a vessel inspected under part B of this subtitle, propelled by machinery or carrying hazardous liquid cargoes in bulk, is not liable to draft in time of war, except for performing duties authorized by the license. When performing those duties in the service of the United States Government, the master, mate, pilot, or engineer is entitled to the highest rate of wages paid in the merchant marine of the United States for similar services. If killed or wounded when performing those duties, the master, mate, pilot, or engineer, or the heirs or legal representatives of the master, mate, pilot, or engineer, are entitled to all the privileges under the pension laws of the United States provided to members of the Armed Forces.