Take-with-a-Grain-of-Salt.
Your question has a couple of options to consider. As an AB you are in a support role, as a 100-ton Mate you are considered as the vessel’s operator, and as the Master you are considered Management. The Coast Guard regulations separate license and endorsements into two schemes, National (domestic) and STCW standards. There are employment opportunities in both schemes.
With that said, the testing for Able Seaman and 100-ton Master is different. Here is my recap of your questions and this topic.
(1) As a National AB, you need to test for Lifeboat(Q445) or Limited Lifeboatman (Q447) endorsement which also requires a demonstration of lowering and recovery of a lifeboat. This is usually completed by taking a USCG Approved Lifeboatman course. See Lifeboatman Checklist, Deck Engineering Guide on page 36, and NMC webpage Sample Exams Deck Ratings for Lifeboatman. I recommend taking the Lifeboat course. This course will also satisfy the STCW Proficiency in Survival Craft, but you will need the 5-day Basic Training Course to have it placed on your MMC.
(2) Next is taking a two-module National Able Seaman Examination. Module A, (Q450), will have 50 questions - 70% pass, relating to subjects on watchstanding as a lookout, i.e., points, bearing drift, and helmsman duties, Helm commands, Navigation General Subjects, Buoyage, and ROR as they apply to being a lookout.
Module B (Q451) Deck General /Safety will have 50 questions - 70% pass, subjects relating to deck nomenclature, knots, blocks and tackles, deck equipment, and deck safety subjects, i.e., firefighting, and lifesaving equipment. See Able Seaman Checklist and Deck Engineering Guide on page 36 and NMC webpage Sample Exams Deck Ratings for Able Seaman.
(3) Then is the Marlinspike Seamanship (knots and splicing) Demonstration. See Deck Engineering Guide on page 37.
National AB Qualifications as per 46 CFR 12.403
- A National AB Special starts with 360 days sea time, it does not have a tonnage requirement.
- A National AB Limited is 540 days but requires sea time on vessels over 100-ton.
- A National AB Unlimited is 1080 days but there is no tonnage requirement. Your sea service needs to be Oceans, Near Coastal or Great Lakes time.
International Deep-Sea Sailing
If you are going to sail oceans, then you will need to complete STCW Courses and Assessments for the position, you wish to sail under. Note: 46 CFR 11.201 “requires that an applicant for STCW must hold the appropriate National Endorsement.”
STCW Deck Endorsements Qualifications as per 46 CFR 12.603.
Prerequisite for STCW endorsements requires completing a USCG Approved Basic Training course.
In this case, a National AB would need to complete the STCW demonstration assessments found in NVIC 06-14 RFPNW and NVIC 14-14 Able Seafarer-Deck. See STCW Rating Checklist for RFPNW and Able Seafarer-Deck.
Shipboard assessments are free assessments and are signed off by a shipboard authorized assessor. An alternative is you can attend a USCG Approved School, at a cost. Ensure the following (1) you meet the sea time requirements found in the STCW Checklist or NVIC 19-14 (2) pay close attention to vessel requirements in each NVICs and (3) the assessor meets the qualifications as outline in the appropriate NVIC. i.e., assessor for both RFPNW and Able Seafarer should have at least 1 year of experience as OICNW on vessels of at least 200 GRT or 500 GT NVIC 19-14. Assessments must be complete shipboard assessments prior to December 31, 2023 and submitted by June 30, 2024 to take advantage of Qualified Assessor Extension policy. See Qualified Assessor Extension Update 082521.
Hope this helps