46 CFR § 11.711 - Tonnage requirements.
(a) In order to obtain a first-class pilot endorsement authorizing service on vessels of unlimited tonnage over a particular route, the applicant must have sufficient experience on vessels of more than 1,600 GRT.
(b) For purposes of this section, an applicant is considered to have sufficient experience if the applicant has 18 months of experience as master, mate, quartermaster, wheelsman, able seaman, apprentice pilot, or in an equivalent capacity, standing regular watches at the wheel or in the pilothouse as part of routine duties, on vessels of 1,600 GRT or more, and two-thirds of the minimum number of roundtrips required for the route have been on vessels of 1,600 GRT or more.
(c) If an applicant does not have sufficient experience on vessels of 1,600 GRT/3,000 GT or more, the endorsement will be for a limited tonnage until the applicant completes a number of additional roundtrips, as determined by the OCMI, within the range contained in § 11.705(b) or (c) of this subpart, as appropriate on vessels of 1,600 GRT/3,000 GT or more.
(d) For purposes of this section, for experience with respect to tonnage on towing vessels, the combined gross tonnage of the towing vessels and the vessels towed will be considered. However, the Coast Guard may require that all or a portion of the required number of roundtrips be obtained on self-propelled vessels of 1,600 GRT or more, when the Coast Guard determines that due to the nature of the waters and the overall experience of the applicant, self-propelled vessel experience is necessary to obtain a first-class pilot endorsement that is not restricted to tug and barge combinations.