Synopsis
EUROCONTROL has been advised of concerns about the use of Decision Altitude/Height (DA(H)) instead of Minimum Descent Altitude (MDA(H)) as the aerodrome operating minima (AOM) on some non-precision approach charts produced by Jeppesen for countries applying “EU Ops”. This has become a source of confusion and has implications for aircraft operators.
Analysis
Commission Regulation EC 859/2008 dated 20 August 2008, EU Ops 1.430(d) 2 (applicable from 16 July 2011) states that “all non-precision approaches shall be flown using the continuous descent final approaches (CDFA) technique”.
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EU Ops, 1.435.9 defines CDFA as, “A specific technique for flying the final-approach segment of a non-precision instrument approach procedure as a continuous descent, without level-off from an altitude/height at or above the Final Approach Fix altitude/height to a point approximately 15m (50ft) above the landing runway threshold or the point where the flare manoeuvre should begin for the type of aircraft shown”. Moreover, Appendix 1 (New) to OPS 1.430, states that, “the missed approach, after an approach has been flown using the CDFA technique, shall be executed when reaching the decision altitude (height…”.
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Note: Additional CDFA guidance material is currently under preparation.
Jeppesen only publish DA(H) on CDFA-based, non-precision approaches where the equivalent national AIP minima is shown as an OCA(H). Where national AIP minima is shown as a MDA(H) or for non-CDFA-based, non-precision approaches, Jeppesen continues to publish MDA(H).
ICAO PANS OPS definitions
- Minimum Descent Altitude/Height (MDA(H)): “a specified altitude or height in a non-precision approach or circling approach below which descent must not be made without the required visual reference”.
- Decision Altitude/Height (DA(H)): “a specified altitude/height in a precision approach or approach with vertical guidance at which a missed approach must be initiated if the required visual reference to continue the approach has not been established”.
- Obstacle Clearance Altitude/Height (OCA(H)): “The lowest altitude or the lowest height above the elevation of the relevant runway threshold or the aerodrome elevation as applicable, used in establishing compliance with appropriate obstacle clearance criteria”.
The DA(H) value shown on the Jeppesen charts is at least equal to the published national AIP (OCA(H)) minima for a non-precision approach. Importantly, however, the DA(H) published on the Jeppesen charts does not include any add-on to account for any height loss during the initiation of a missed approach. This is not mentioned directly on the charts, but it is described in the Jeppesen Briefing Bulletin JEP 08-D and in the legend pages to the Jeppesen Airway Manual.
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EU Ops 1.430 (a)1 states that, “an operator shall establish, for each aerodrome planned to be used, aerodrome operating minima…”
Your Attention Is Required
Aircraft operators are invited to:
- Note the issue above specifically with a review of the need to consider the requirement for an add-on factor to account for height loss at missed approach initiation.
- Share their operational experiences.
It is critical to flight safety that pilots brief the DA(H) or MDA(H) (as appropriate) so that there is no ambiguity as to what minimums are being used irrespective of the type of approach being flown.
Further Reading
- Commission Regulation EC 859/2008 (EU Ops) dated 20 August 2008.
- ICAO Doc – 8168 PANS OPS
- Jeppesen Airway Manual
- Jeppesen Briefing Bulletin JEP 08-D – 26 Sep 08
- Draft Implementing Rule for Air Operations of Community Operators (EASA NPA 2009-02B) (CDFA Guidance pages 155-165)
SKYbrary
- Decision Altitude/Height (DA/DH)
- Minimum Descent Altitude/Height (MDA/MDH)
- Aerodrome Operating Minima
- EU-OPS
Disclaimer
© European Organisation for Safety of Air Navigation (EUROCONTROL) February 2010. This alert is published by EUROCONTROL for information purposes. It may be copied in whole or in part, provided that EUROCONTROL is mentioned as the source and to the extent justified by the non-commercial use (not for sale). The information in this document may not be modified without prior written permission from EUROCONTROL. The use of the document is at the user’s sole risk and responsibility. EUROCONTROL expressly disclaim any and all warranties with respect to any content within the alert, express or implied.
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