AMC3 CAT.OP.MPA.110 Aerodrome operating minima

CAA ORS9 Decision No. 47

Text in magenta in force from 30 October 2025

NPA, APV, CAT I OPERATIONS

(a) The decision height (DH) to be used for a non-precision approach (NPA) flown with the continuous descent final approach (CDFA) technique, approach procedure with vertical guidance (APV) or category (CAT) I operation should not be lower than the highest of:

(1) the minimum height to which the approach aid can be used without the required visual reference;

(2) the obstacle clearance height (OCH) for the category of aircraft;

(3) the published approach procedure DH where applicable;

(4) the system minimum specified in Table 3; or

(5) the minimum DH specified in the aircraft flight manual (AFM) or equivalent document, if stated.

(b) The minimum descent height (MDH) for an NPA operation flown without the CDFA technique should not be lower than the highest of:

(1) the OCH for the category of aircraft;

(2) the system minimum specified in Table 3; or

(3) the minimum MDH specified in the AFM, if stated.

Table 3

System minima

Facility	Lowest DH/MDH (ft)
ILS/MLS/GLS	200
GNSS/SBAS (LPV)	200
GNSS (LNAV)	250
GNSS/Baro-VNAV (LNAV/ VNAV)	250
LOC with or without DME	250
SRA (terminating at ½ NM)	250
SRA (terminating at 1 NM)	300
SRA (terminating at 2 NM or more)	350
VOR	300
VOR/DME	250
NDB	350
NDB/DME	300
VDF	350

DME: distance measuring equipment;

GNSS: global navigation satellite system;

ILS:    instrument landing system;

LNAV: lateral navigation;

LOC: localiser;

LPV:    localiser performance with vertical guidance

SBAS: satellite-based augmentation system;

SRA:    surveillance radar approach;

VDF: VHF direction finder;

VNAV: vertical navigation;

VOR: VHF omnidirectional radio range.

The text below will replace the text above on 30 October 2025:

DETERMINATION OF DH/MDH FOR INSTRUMENT APPROACH OPERATIONS — AEROPLANES

1. The decision height (DH) to be used for a 3D approach operation, or a 2D approach operation flown using the continuous descent final approach (CDFA) technique, should not be lower than the highest of:

   1. the obstacle clearance height (OCH) for the category of aircraft;

   2. the published approach procedure DH or minimum descent height (MDH) where applicable;

   3. the system minima specified in Table 4;

   4. the minimum DH permitted for the runway specified in Table 5; or

   5. the minimum DH specified in the aircraft flight manual (AFM) or equivalent document, if stated.

2. The MDH for a 2D approach operation flown not using the CDFA technique should not be lower than the highest of:

   1. the OCH for the category of aircraft;

   2. the published approach procedure MDH where applicable;

   3. the system minima specified in Table 4;

   4. the lowest MDH permitted for the runway specified in Table 5; or

   5. the lowest MDH specified in the AFM, if stated.

Table 4

System minima — aeroplanes

Facility	Lowest DH/MDH (ft)
ILS/MLS/GLS	200
GNSS/SBAS (LPV)	200*
Precision approach radar (PAR)	200
GNSS/SBAS (LP)	250
GNSS (LNAV)	250
GNSS/Baro VNAV (LNAV / VNAV)	250
LOC with or without DME	250
SRA (terminating at ½ NM)	250
SRA (terminating at 1 NM)	300
SRA (terminating at 2 NM or more)	350
VOR	300
VOR/DME	250
NDB	350
NDB/DME	300
VDF	350

* For localiser performance with vertical guidance (LPV), a DH of 200 ft may be used only if the published FAS datablock sets a vertical alert limit not exceeding 35 m. Otherwise, the DH should not be lower than 250 ft.

Table 5

Runway type minima — aeroplanes

Runway type	Approach type	Lowest DH/MDH (ft)
Instrument runway	Precision approach (PA) runway, category I	200
Instrument runway	NPA runway	250
Non-Instrument runway	Non-instrument runway	Circling minima as shown in Table 15

 

3. Where a barometric DA/H or MDA/H is used, this should be adjusted where the ambient temperature is significantly below international standard atmosphere (ISA). GM8 CAT.OP.MPA.110 ‘Low temperature correction’ provides a cold temperature correction table for adjustment of minimum promulgated heights/altitudes.