AMC2 SPA.HOFO.125 Offshore standard approach procedures (OSAPs)

CAA ORS9 Decision No. 47

Text in magenta in force from 30 October 2025

OSAP — ORIGINAL EQUIPMENT MANUFACTURER (OEM) — CERTIFIED APPROACH SYSTEM

Where an OSAP is conducted to a non-moving offshore location (i.e. fixed installation or moored vessel), and an original equipment manufacturer (OEM)-certified approach system is available, the use of automation to reach a reliable GNSS position for that location should be used to enhance the safety of the OSAP.

The OSAP should meet the following requirements:

  1. The OEM-certified approach system should be approved in accordance with the applicable airworthiness requirements for operations at night and in IMC.

  2. The aircraft should be equipped with a radar altimeter and a suitable airborne radar.

  3. The GNSS position of the installation should be retrieved from the area navigation system database or by manual entry if the aircraft flight management system will allow for that.

  4. The approach system vertical path should be a Baro VNAV or a GNSS SBAS vertical source type. The radar height should be cross-checked (either automatically or by the crew) to avoid erroneous QNH selection.

  5. The descent angle should be of a maximum of 4°. Up to 6° could be acceptable only if the GS is reduced to 60 kt.

  6. The minimum descent height (MDH) should not be less than 50 ft above the elevation of the helideck:

    1. the MDH for an approach should not be lower than:

      1. 200 ft by day; or

      2. 300 ft by night; and

    2. the MDH for an approach leading to a circling manoeuvre should not be lower than:

      1. 300 ft by day; or

      2. 500 ft by night.

  7. The minimum descent altitude (MDA) may only be used if the radio altimeter is unserviceable. The MDA should be a minimum of the MDH + 200 ft and should be based on a calibrated barometer at destination or on the lowest forecast barometric pressure adjusted to sea level (QNH) for the region.

  8. The MDA/H for a single-pilot ARA should be 100 ft higher than that calculated in accordance with (f) and (g) above. The decision range should not be less than 1 NM.

  9. The approach system lateral path guidance should be capable of at least performance monitoring and alerting function of RNP 0.3 NM up to the missed approach point (MAPt), then RNP 1.0 NM to missed approach holding point.

  10. The horizontal flight path should be defined in accordance with the RNP capability of the approach system (e.g. offset no lower than the RNP capability).

  11. The maximum acceptable offset angle between the final inbound course and the installation should be 30°.

  12. Before commencing the final approach, the pilot-in-command/commander should ensure that a clear path exists on the radar screen for the final and missed approach segments. If lateral clearance from any obstacle is less than the navigation performance, the pilot-in-command/commander should:

    1. approach to a nearby target structure and thereafter proceed visually to the destination structure; or

    2. make the approach from another direction leading to a circling manoeuvre.

  13. The minimum decision range (MDR) should not be less than 0.75 NM. The maximum acceptable GS at the MAPt for a 0.75-NM MDR should be 80 kt.

  14. The segment from the MAPt to destination should not be flown in tailwind conditions. The approach course should be selectable accordingly.

  15. The aircraft should have the capability to compare the airborne radar picture and GNSS range and bearing data to cross-check the position of the offshore location.