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8.1 Type Approval Questionnaire

The term type approval describes the process of testing and verification which leads to a VLD being accepted for use in a given VMS system. That type approval processes of national and regional agencies be based on certain norms and standards is essential if vessels commissioned for one VMS system are to be accepted with minimum formalities for operation in another.

Essentially, the type approval process is parallel to that cited in section 7.1. The fundamental difference is that this latter process certifies simply that the equipment is suitable for operation in the maritime environment. The type approval process, on the other hand, certifies that the equipment conforms to all of the operational and performance specifications for VMS operation. In addition to meeting the requirements for maritime operation, for example, a rigorous VMS type approval process will insure that the VLD is sufficiently protected against the possibility of tampering to avoid monitoring.

This process is generally executed in two series of tests, one each off-line and on-line. In the former, the VLD is tested using a test-bed, or simulator, of the VMS system. When these trials are successfully completed, the VLD is tested on-line, i.e. as though it were an actual vessel being monitored in real-time.

The basis of the tests are the requirements outlined in section 6. A sequence of operations is carried out to confirm that the equipment sends its entry into service message upon being turned on, that its position reports are delivered in the correct format, that it responds to polls, that its reporting frequency can be reprogrammed remotely, and that it sends a correct end of service message upon being turned off.

8.1 Type Approval Questionnaire

Perhaps the simplest way to create a normalized type approval process would be for monitoring agencies to adopt a standardized questionnaire and to certify that an inspection of each installation they certify would return correct answers to all of the questions. A suitable list of mandatory questions would include:

1. Is the VLD’s unique identifier stored in non-volatile memory which constitutes part of the system’s unmodifiable firmware?

2. Does the VLD have a clearly visible, irremovable, irreplacable and unmodifiable external serial number or other unique identifier?

3. Is the VLD capable of detecting that it is incapable of sending or receiving messages because of antenna blockage or disconnection?

4. Is the entire communication sequence from the VLD to the VMS monitoring authority, including relay by the satellite service provider, secure and immune to interception, under reasonable circumstances?

5. Does the satellite system employed offer full, continuous global coverage (with the exception of the polar regions) or, as a minimum, continuous coverage of the VMS area?

6. Are the positions received accurate within the specified tolerance?

7. Do received position reports contain, in addition to the position, the VLD’s unique identifier and the time of the fix?

8. Is message delivery completed within specified tolerances?

9. Is transmission of position reports unobservable aboard the vessel, under normal circumstances?

10. Is the VLD sufficiently protected against having the automated position reporting function altered or disabled, other than by the monitoring authority?

Depending on a VMS’s individual requirements, any or all of the following questions could also be included:
1. Is the VLD capable of providing independently calculated speed and course (if required)?

2. Does the VLD transmit a correctly formatted “entry into service” message upon being turned on?

3. Does the VLD transmit a correctly formatted “end of service” message upon being turned off?

4. Does the VLD transmit an “interrupted service” message when it has been out of service for more than 15 minutes due to abrupt power cut or due to incapability of sending or receiving messages because of antenna blockage or disconnection?

5. Can the frequency of position reports be altered remotely?

6. Does the VLD respond automatically and immediately to a remote request for a position report?

7. Does the VLD have the capability to transmit free-text or pre-formatted messages created on board the vessel?

Positive answers to all of the above questions would certify that a VMS installation met the necessary standards for international operation.

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