Equivalent Safety Finding UK.ESF.F.0003 Indications Removal from Primary Flight Displays During Ground Phases

For comments on the proposal that the CAA introduces an equivalent safety finding concerned with removal of some indications from the primary flight display during ground phases, when using a 3D Airport Moving Map (AMM) feature.

The UK CAA is consulting on an Equivalent Safety Finding that is applicable to CS-23 Normal Category Aeroplanes.

This Equivalent Safety Finding provides the compensating factors to reach an equivalent level of safety to direct compliance with CS-23 23.1303, 23.1311(a)(3) & 23.1321(d).

The Consultation Paper Equivalent Safety Finding UK.ESF.F.0003 Issue 1 provides the full detail of the identified issue, and the associated Equivalent Safety Finding.

We received 1 response.

This response highlighted the importance of preventing erroneous activation of the 3D Airport Moving Map (AMM) feature and highlighted potential failure effects of the AMM feature and the aircraft’s GPS system.

We acknowledge the response and thank the responder for their suggestion.

The comment is not incorporated. CAA consider that this comment is addressed by the following mitigations detailed in the Equivalent Safety Finding Consultation Paper UK.ESF.F.0003 Issue 1:

• If the indication is failed while removed (e.g. failure of the bank and pitch information when not displayed), the corresponding alerting is as efficient as when the indication is available.
• Mitigations have been put in place to compensate for the reduced exposure of flight crew to failures that may not be detected by the systems (e.g. frozen heading and airspeed on both sides).
• If the removed indication fails to be displayed when required or is erroneously removed during other flight phases (e.g. in cruise), the failure effect and compounding effects meet all applicable certification specifications.
• Appropriate procedures when needed to ensure Continued Safe Flight and Landing and to recover the removed information are introduced in the Aeroplane Flight Manual.