Section 11.455 - Requirements for master of Great Lakes and inland self-propelled vessels of less than 100 GRT(a) The minimum service required to qualify an applicant for an endorsement as master of Great Lakes and inland self-propelled vessels of less than 100 GRT is 1 year of total service in the deck department of self-propelled, sail, or auxiliary sail vessels. To obtain authority to serve on the Great Lakes, 3 months of the required service must have been on Great Lakes waters; otherwise the endorsement will be limited to the inland waters of the United States (excluding the Great Lakes).(b) To obtain an endorsement for sail or auxiliary sail vessels, the applicant must submit evidence of 6 months of service on sail or auxiliary sail vessels. The required 6 months of service may have been obtained prior to issuance of the endorsement.(c) All endorsements issued for master or mate of vessels of less than 100 GRT are issued in tonnage increments based on the applicant's qualifying experience in accordance with the provisions of § 11.422 of this subpart.