46 CFR 11.480: Radar Observer endorsement requirements

Last reviewed: October 14, 2026

This section sets the requirements an applicant must meet to qualify as a Radar Observer. It lists three endorsements and where each is valid. Applicants generally must complete a Coast Guard-approved course and provide the training certificate, with renewal alternatives in paragraphs (f) and (g).

Applies toApplicants for a Radar Observer endorsement or for renewal of one, and applicants for renewal of an MMC.

What it says

  1. If an applicant meets the requirements of this section, one of three Radar Observer endorsements is added to their MMC: Unlimited, Inland Waters and Gulf Intracoastal Waterways (GIWW), or Rivers.

    46 CFR 11.480(b)“If an applicant meets the requirements of this section, one of the following Radar Observer endorsements will be added to their MMC:”

  2. Radar Observer-Unlimited is valid on all waters.

    46 CFR 11.480(c)“Radar Observer-Unlimited is valid on all waters.”

  3. Radar Observer-Inland Waters and GIWW is valid only for those waters other than the Great Lakes covered by the Inland Navigational Rules.

    46 CFR 11.480(c)“Radar Observer-Inland Waters and GIWW is valid only for those waters other than the Great Lakes covered by the Inland Navigational Rules.”

  4. Radar Observer-Rivers is valid only on any river, canal, or similar body of water designated by the OCMI, but not beyond the boundary line.

    46 CFR 11.480(c)“Radar Observer-Rivers is valid only on any river, canal, or similar body of water designated by the OCMI, but not beyond the boundary line.”

  5. Except as provided by paragraphs (f) or (g), each applicant for a Radar Observer endorsement or its renewal must complete the appropriate Coast Guard-approved course, receive the certificate of training, and provide the certificate or a copy to the Coast Guard in person, by mail, or other electronic means.

    46 CFR 11.480(d)“must complete the appropriate course approved by the Coast Guard, receive the appropriate certificate of training, and provide the certificate or a copy of the certificate to the Coast Guard in person, by mail, or other electronic means.”

  6. A Radar Observer endorsement issued under this section is valid until the expiration of the mariner's MMC.

    46 CFR 11.480(e)“A Radar Observer endorsement issued under this section is valid until the expiration of the mariner's MMC.”

  7. The Coast Guard will accept documentary evidence of 1 year of relevant sea service within the last 5 years in a position that routinely uses radar for navigation and collision avoidance on vessels equipped with radar as meeting the refresher or re-certification requirements of paragraph (d).

    46 CFR 11.480(g)“1 year of relevant sea service within the last 5 years in a position that routinely uses radar for navigation and collision avoidance purposes on vessels equipped with radar”

  8. An MMC renewal applicant who does not show evidence of meeting the renewal requirements of paragraph (d), (f), or (g) will not have a Radar Observer endorsement placed on their MMC.

    46 CFR 11.480(h)“will not have a Radar Observer endorsement placed on their MMC.”

Common questions

How long is a Radar Observer endorsement valid?

A Radar Observer endorsement issued under this section is valid until the expiration of the mariner's MMC.

“A Radar Observer endorsement issued under this section is valid until the expiration of the mariner's MMC.”

Can I renew a Radar Observer endorsement without taking a course?

A mariner may renew by providing evidence of meeting the requirements in § 10.227(e)(1)(v) of this subchapter. The Coast Guard will also accept 1 year of relevant sea service within the last 5 years under paragraph (g).

“A mariner may also renew their Radar Observer endorsement by providing evidence of meeting the requirements in § 10.227(e)(1)(v) of this subchapter.”

Where is a Radar Observer-Rivers endorsement valid?

It is valid only on any river, canal, or similar body of water designated by the OCMI, but not beyond the boundary line.

“Radar Observer-Rivers is valid only on any river, canal, or similar body of water designated by the OCMI, but not beyond the boundary line.”

The text of 46 CFR 11.480

Electronic Code of Federal Regulations (eCFR), current as of April 16, 2026 · Read it on eCFR

Radar Observer

(a) This section contains the requirements that an applicant must meet to qualify as a Radar Observer.

(b) If an applicant meets the requirements of this section, one of the following Radar Observer endorsements will be added to their MMC:

(1) Radar Observer-Unlimited.

(2) Radar Observer-Inland Waters and Gulf Intracoastal Waterways (GIWW).

(3) Radar Observer-Rivers.

(c) Radar Observer-Unlimited is valid on all waters. Radar Observer-Inland Waters and GIWW is valid only for those waters other than the Great Lakes covered by the Inland Navigational Rules. Radar Observer-Rivers is valid only on any river, canal, or similar body of water designated by the OCMI, but not beyond the boundary line.

(d) Except as provided by paragraphs (f) or (g) of this section, each applicant for a Radar Observer endorsement or for renewal of a Radar Observer endorsement must complete the appropriate course approved by the Coast Guard, receive the appropriate certificate of training, and provide the certificate or a copy of the certificate to the Coast Guard in person, by mail, or other electronic means.

(e) A Radar Observer endorsement issued under this section is valid until the expiration of the mariner's MMC.

(f) A mariner may also renew their Radar Observer endorsement by providing evidence of meeting the requirements in § 10.227(e)(1)(v) of this subchapter.

(g) The Coast Guard will accept on-board training and experience through acceptable documentary evidence of 1 year of relevant sea service within the last 5 years in a position that routinely uses radar for navigation and collision avoidance purposes on vessels equipped with radar as meeting the refresher or re-certification requirements of paragraph (d) of this section. This also applies to mariners applying for raises of grade or new endorsements under § 10.231 of this subchapter.

(h) An applicant for renewal of an MMC who does not provide evidence of meeting the renewal requirements of paragraph (d), (f), or (g) of this section will not have a Radar Observer endorsement placed on their MMC.

Sections it refers to

The plain-English explanation on this page was written with AI from the regulation text above and checked automatically before publishing: every quote appears in the text, every number comes from it, and a second model confirmed each statement adds nothing the text doesn't say. Regulation text current as of April 16, 2026. The regulation text governs. RegKnot is not affiliated with the U.S. Coast Guard.