JEPPESEN GENERAL AIRWAY MANUAL (Issue Date 1 JUL 21)

FLIGHT PHASE SPECIFIC PRINCIPLES

DEPARTURE PROCEDURES

Procedure design gradient (PDG)

3.1.1.1  The PDG is used by the procedure designer to identify critical obstacles in the departure
and to specify a minimum climb gradient for the procedure. The departure route may be adjusted
to minimize the PDG consistent with other constraints.
3.1.1.2  Unless otherwise published, a PDG of 3.3 per cent (5.0 per cent for CAT H) is assumed.
3.1.1.3  The PDG is based on:

a. an obstacle identification surface (OIS) having a 2.5 per cent gradient (4.2 per cent for CAT

H) or a gradient determined by the most critical obstacle penetrating the surface, whichever
is the higher; and

b. an additional margin of 0.8 per cent.

3.1.1.4 For conversion of climb gradients to rates of climb for operational use, see Part II, Sec-
tion 2, Chapter 1, Figure II-2-1-2.

Obstacle clearance

3.1.2.1 For other than turning departures and CAT H point-in-space (PinS) departures, the MOC
provided by the procedure is determined as a factor of the distance from the departure end of the
runway (DER).
3.1.2.2 A figure of 0.8 per cent of this distance is used to calculate the MOC. Some example
values are shown in Tables A-3-1 and A-3-2.

Table A-3-1. Departure MOC for given distance from DER

Distance from DER (NM)

Distance from DER (ft)

MOC (ft)

0
1
2
3
4
5

10
21

6076

12152
18228
24304
30380
60760

127596

49
97

146
194
243
486

1021

3.1

3.1.1

3.1.2

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Table A-3-2. Departure MOC for given distance from DER (SI Units)

Distance from DER (km)

MOC (m)

0
2
4
6
8

10
20
40

16
32
48
64
80

160
320

1.2.3 The MOC in a turning departure is a fixed value of 75 m (246 ft) (for CAT H, 65 m (213 ft)).
1.2.4 CAT H PinS departures are based on visual or visual flight rules (VFR) flight to the initial
departure fix (IDF), so no MOC is provided in this segment. For “proceed visually,“ PinS depar-
tures, the visual segment design gradient (VSDG) is established to provide a MOC of 30 m at the
IDF. The MOC continues to expand with distance.

EN-ROUTE

GENERAL

3.2.1.1 Two methods can be used to determine en-route obstacle clearance areas:

a. a simplified method, which is the standard method; and
b. a refined method, which can be used when the simplified method is too constraining.

Obstacle clearance areas

In the simplified method, the obstacle clearance area is divided into a central primary area and
two lateral buffer areas, which use half the MOC value. In the refined method, the obstacle clear-
ance area is divided into a central primary area and two lateral secondary areas, which use the
progressively reducing MOC. The width of the primary area corresponds to 95 per cent probability
of containment (2 SD). The total width of the area corresponds to 99.7 per cent probability of con-
tainment (3 SD).

Reductions to secondary area widths

Secondary areas for en-route operations may be reduced when justified by factors such as:

a. relevant information on flight operational experience;
b. regular flight inspection of facilities to ensure better than standard signals; and/or

c. surveillance.

3.2

3.2.1

3.2.1.2

3.2.1.3

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3.2.1.4.2 A minimum obstacle clearance altitude (MOCA) is determined and published for each
segment of the route. The MOCA provides the required MOC above obstacles contained inside
the obstacle clearance areas.

En-route clearance areas – conventional routes

Area without track guidance

When track guidance is not provided, for example, outside the coverage of navigation facilities
along the route, the primary area splays at an angle of 15° from its width at the last point where
track guidance was available. The width of the buffer area (simplified method) or the secondary
area (refined method) is progressively reduced to zero, ending in an area without track guidance
where the full MOC is applied.

Area width

3.2.2.2.1 Abeam the facility, the total area has a constant width of 18.5 km (10.0 NM), which is
comprised of the primary area and a buffer area. The primary area maintains a constant width of
9.3 km (5.0 NM) on either side of the nominal track.The buffer area also maintains a constant
width of 9.3 km (5.0 NM) with half of this area on either side of the primary area.
3.2.2.2.2 When the distance from the facility increases beyond:

a. 92.3 km (49.8 NM) for very high frequency omnidirectional radio range (VOR); and
b. 60 km (32 NM) for non-directional beacon (NDB),

the widths of the primary and buffer areas are increased by an angle of splay which is determined
by the type of facility. The angle of splay is depicted in Table A-3-3.

Table A-3-3. Angle of splay for en-route navigation aids

Primary area

Buffer area

VOR

5.7°

9.1°

NDB

7.95°

13.0°

NOTE: The area widths and splay angles outlined in 3.2.2.2.1 and 3.2.2.2.2 apply to the simplified
method. For the refined method, the VOR widths are 2 NM less and angles for both VOR and
NDB are slightly larger.
3.2.2.2.3 The buffer area is further increased by an additional fixed width on the outside of the
buffer area, parallel to its edge. This width is:

a. 3.7 km (2.0 NM) for VOR; and
b. 4.6 km (2.5 NM) for NDB.

En-route clearance areas – PBN routes

3.2.3.1 En-route oceanic and remote areas. The applicable navigation specifications are:

a. RNAV 10;

3.2.2

3.2.2.1

3.2.2.2

3.2.3

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b. RNP 4;

c. RNP 2;

d. A-RNP.

3.2.3.2 The clearance area ½ A/W established by the formula:
½ A/W = 1.5 x navigation specification navigation accuracy requirement + en-route buffer value of
2 NM.
NOTE: ln some cases, such as RNAV 5, a smaller value than the required accuracy of the navi-
gation specification is used, depending on the nature of the errors and the integrity monitoring
alarm limit of the system.
3.2.3.3 Table A-3-4 presents the applicable navigation accuracy requirements and clearance ½
A/W.

Table A-3-4. En-route oceanic/remote ½ A/W

Navigation specification

Accuracy requirement (NM)

½ A/W (NM)

RNAV 10

RNP 4

RNP 2

3.2.3.4 En-route continental areas. The applicable navigation specifications are:

a. RNAV 5;
b. RNAV 2;

c. RNP 2;

d. A-RNP;
e. RNP 0.3.

3.2.3.5 Table A-3-5 depicts the en-route continental clearance area ½ A/W for area navigation
routes.

Table A-3-5. En-route continental ½ A/W

Navigation specification

Accuracy requirement (NM)

½ A/W (NM)

RNAV 5

5.77

RNAV 2 (GNSS)

RNAV 2 (DME/DME)

4.26

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Table A-3-5. En-route continental ½ A/W (continued)

Navigation specification

Accuracy requirement (NM)

½ A/W (NM)

RNP 2

RNP 0.3

0.3

1.45

This figure is calculated using 2.51 NM instead of 5 NM.

MOC in mountainous areas

3.2.4.1 In mountainous areas, the MOC is increased, depending on variation in terrain elevation
as shown in the Table A-3-6.

Table A-3-6. MOC in mountainous areas

Elevation

MOC

Between 900 m (3000 ft) and 1500 m (5000 ft)

450 m (1476 ft)

Greater than 1500 m (5000 ft)

600 m (1969 ft)

3.2.4.2 Mountainous areas are identified by the State and promulgated in the State Aeronautical
Information Publication.

ARRIVAL AND APPROACH PROCEDURES

Categories of aircraft

3.3.1.1  Aircraft performance has a direct effect on the airspace required for the various manoeu-
vres associated with the conduct of instrument approach procedures. The most significant per-
formance factor is aircraft speed.
3.3.1.2  Accordingly, categories of typical aircraft have been established. These categories pro-
vide a standardized basis for relating aircraft manoeuvrability to specific instrument approach pro-
cedures. For precision approach procedures, the dimensions of the aircraft ate also a factor for
the calculation of the obstacle clearance height (OCH). For Category DL aircraft, an additional
obstacle clearance altitude/height (OCA/H) is provided, when necessary, to take into account the
specific dimensions of these aircraft.
3.3.1.3  The criterion taken into consideration for the classification of aeroplanes by categories is
the indicated airspeed at threshold (V

), which is equal to the stall speed V

multiplied by 1.3, or

stall speed V

s1g

multiplied by 1.23 in the landing configuration at the maximum certificated landing

mass. If both V

and V

s1g

are available, the higher resulting V

shall be applied.

3.3.1.4  The landing configuration that is to be taken into consideration is defined by the operator
or by the aircraft manufacturer.
3.3.1.5  Aircraft categories are listed in Part II, Section 5, Chapter 1.
3.3.1.6  The instrument approach chart (IAC) will specify the individual categories of aircraft for
which the procedure is approved. Normally, procedures will be designed to provide protected air-

3.2.4

3.3

3.3.1

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space and obstacle clearance for aircraft up to and including Category D. However, where air-
space requirements are critical, procedures may be restricted to lower speed categories.
3.3.1.7 Alternatively, the procedure may specify a maximum IAS for a particular segment. In any
case, it is essential that pilots comply with the procedures and information depicted on instrument
flight charts and the appropriate flight parameters shown in Tables II-5-1-1 and II-5-1-2 if the air-
craft is to remain in the areas developed for obstacle clearance purposes.

Helicopters

3.3.1.8.1 The stall speed method of calculating aircraft category does not apply to helicopters.
Pilots flying helicopters may utilize instrument approach procedures promulgated for Category A
aeroplanes. However, specific procedures may be developed for helicopters, and these shall be
clearly designated “CAT H”. Category H procedures shall not be promulgated on the same IAC as
joint helicopter/aeroplane procedures.
3.3.1.8.2 It is intended that helicopter only procedures should be designed using the same con-
ventional techniques and practices as those pertaining to Category A aeroplanes. Some criteria
such as minimum airspeeds and descent gradients may be different, but the principles are the
same. For CAT H procedures, the maximum speed to be used on the final approach and missed
approach segments is charted.

Descent gradient

3.3.2.1  In instrument approach procedure design, adequate space is allowed for descent from
the facility, fix or waypoint crossing altitude/height to the runway threshold for straight-in approach
or to OCA/H for circling approaches.
3.3.2.2  Adequate space for descent is provided by establishing a maximum allowable descent
gradient for each - segment of the procedure. The optimum descent gradient/angle in the FAS of
a procedure with FAF is 5.2 per cent/3.0° (52 m/km (318 ft/NM)).
3.3.2.3  Where a steeper descent gradient is necessary, the maximum permissible is:

a. 6.5 per cent/3.7° (65 m/km (395 ft/NM)) for Category A and B aircraft;
b. 6.1 per cent/3.5° (61 m/km (370 ft/NM)) for Category C, D and E aircraft, and

c. 10 per cent (5.7°) for Category H.

3.3.2.4 For procedures with VOR or NDB on aerodrome and no FAF, rates of descent in the
final approach phase are given in Table A-3-7. In the case of a precision approach, the operation-
ally preferred glide path angle is 3.0° as specified in Annex 10, Volume I.
3.3.2.5 For ILS, the minimum descent gradient is 2.5°.

3.3.1.8

3.3.2

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Table A-3-7. Rate of descent in the FAS of a procedure with no FAF

Aircraft categories

Rate of descent

Minimum

Maximum

A, B

2 m/s

(394 ft/min)

3.33 m/s

(655 ft/min)

C, D, E

3 m/s

(590 ft/min)

5.08 m/s

(1000 ft/min)

RNP APCH “Y“ and “T“ bar construction

3.3.3.1 Offset IAFs. Offset IAFs in procedures based on the “Y” or “T” bar design concept for
RNP APCH procedures are aligned such that a course change of 70° to 90° is required at the IF.
A capture region is associated with each IAF of the RNP APCH procedure from which the aircraft
will enter the procedure. The capture region for tracks inbound to the offset IAFs extends 180°
about the IAFs, thus providing a Sector 3 entry in cases where the track change at the IF is 70°.
The central IAF is aligned with the intermediate segment, the angle being identical to the track
change at the IF for the corresponding offset IAF. In this way, there are no gaps between the cap-
ture regions of all IAFs regardless of the course change at the IF. Its capture region is 70° to 90°
either side of the final track. For turns greater than 110° at the IAFs, Sector 1 or 2 entries should
be used.
3.3.3.2 The initial approach segments have no maximum length. The optimum length is 9.3 km
(5.0 NM). The minimum segment length is established by using the highest initial approach speed
of the fastest category of aircraft for which the approach is designed and the minimum distance
between waypoints required by the aircraft avionics in order to correctly sequence the waypoints.

Minimum obstacle clearance (MOC)

Minimum sector altitudes (MSAs)

3.3.4.1.1 MSAs are established for each aerodrome where instrument approach procedures
have been established. Each MSA is calculated by:

a. taking the highest elevation in the sector concerned;
b. adding a clearance of at least 300 m (984 ft); and

c. rounding the resulting value up to-the next higher 50 m or 100 ft increment, as appropriate.

3.3.4.1.2  If the difference between sector altitudes is insignificant (i.e. in the order of 100 m or
300 ft as appropriate) a minimum altitude applicable to all sectors may be established.
3.3.4.1.3  A minimum altitude shall apply within a radius of 46 km (25 NM) of the significant point,
the ARP, or the heliport reference point (HRP) on which the instrument approach is based. The
MOC when flying over mountainous areas should be increased by as much as 300 m (984 ft).
3.3.4.1.4  Obstacles within a buffer zone of 9 km (5 NM) around the boundaries of any given
sector shall be considered as well.

3.3.3

3.3.4

3.3.4.1

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Initial and intermediate segments

3.3.4.2.1 MOC for the initial segment of an approach is 300 m (984 ft).
3.3.4.2.2 MOC for the intermediate segment of an approach is 150 m (492 ft). The altitudes/
heights selected by application of the obstacle clearance specified shall be rounded upwards to
the next 50 m or 100 ft, as appropriate.

Non-precision approaches (NPAs)

3.3.4.3.1 For an NPA with a FAF, a minimum of 75 m (246 ft) clearance is provided.
3.3.4.3.2 For an NPA without a FAF this figure is increased to 90 m (295 ft).

Approach with vertical guidance (APV) approaches

3.3.4.4.1  General. APV approaches are 3D approach operations. Criteria for these procedures
support stabilized flight on FAS. APV procedures are based on equipment that does not meet the
requirements for precision approaches.
3.3.4.4.2  Obstacle clearance criteria. There are two different sets of criteria used for APV proce-
dure design (APV/barometric vertical navigation (baro-VNAV) and SBAS APV-I criteria). Each set
of criteria was prepared to address a specific section of the RNP APCH navigation specification,
as described in Doc 9613.
3.3.4.4.2.1  APV/baro-VNAV criteria are designed to address procedure construction in accord-
ance with Doc 9613, specifically Section A of the RNP APCH navigation specification, coupled
with baro-VNAV vertical guidance as described in Attachment A of Doc 9613.
3.3.4.4.2.2  SBAS APV-I criteria were developed to meet the requirements of Section B of the
RNP APCH navigation specification.
3.3.4.4.3  Criteria differences. Procedure construction for Section A procedures provides obsta-
cle protection within a maximum-to-minimum temperature band published on the approach chart.
The use of a remote altimeter setting source is not permitted with LNAV/VNAV procedures utiliz-
ing baro-VNAV vertical guidance. Procedure construction is based on the linear navigation guid-
ance provide by GNSS/baro-VNAV equipment.
3.3.4.4.3.1  Procedure construction for Section B procedures utilizes criteria that cater to the
angular lateral and vertical guidance on the FAS provided by SBAS equipment. Since barometric
altimetry input is not used in generating vertical guidance with SBAS, there are no temperature
restrictions or remote altimeter setting source restrictions with the SBAS criteria.
3.3.4.4.4  The minimum published decision height (DH) for APV procedures, regardless of the
criteria set used, is 75 m (250 ft).

Precision approaches

3.3.4.5.1 Precision instrument approach criteria exist for ILS, microwave landing systems (MLS),
GBAS landing systems (GLS) and SBAS CAT I.
3.3.4.5.2 Obstacle clearance altitudes for precision approaches can be calculated by a number
of different methods. However, all methods use assessment surfaces to discriminate between sig-
nificant and insignificant obstacles.

3.3.4.2

3.3.4.3

3.3.4.4

3.3.4.5

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3.3.4.5.3 The highest significant obstacle on the approach (or missed approach, converted to an
equivalent height) is used to determine the obstacle clearance altitude by adding a height loss
margin to its elevation. The margin is dependent on the aircraft category and whether pressure or
radio altimetry is used. The values are shown in Table A-3-8.

Table A-3-8. Height loss/altimeter margin for maximum V

by aircraft category

Aircraft category

(maximum V

)

Margin using radio altimeter

Margin using pressure altime-

ter

Metres

Feet

Metres

Feet

A – 169 km/h (90 kt)

130

B – 223 km/h (120 kt)

142

C – 260 km/h (140 kt)

150

D – 306 km/h (165 kt)

161

H – 167 km/h (90 kt)

115

NOTE 1: CAT H speed is the maximum final approach speed, not V

NOTE 2: Since height loss varies with speed, the table shows only the calculation for a reference
speed, which is the upper limit for each category.
3.3.4.5.4 It should be recognized that no allowance has been included in the table for any
abnormal meteorological conditions; for example, wind shear and turbulence.

Missed approach – non-precision approach (NPA)

3.3.4.6.1  The beginning MOC on the missed approach is the value used for the final segment of
the approach.
3.3.4.6.2  This initial phase continues until the start of climb (SOC); this marks the commence-
ment of the intermediate phase of the missed approach. The SOC is defined by reference to air-
craft category missed approach speed, a 10 kt tailwind and assumed delays to cater for pilot reac-
tion time and aircraft configuration changes. No turns are designed prior to the SOC.
3.3.4.6.3  The MOC in the intermediate phase is 30 m (98 ft) when no turns are employed, other-
wise 50 m (164 ft). Any track change greater than 15° is defined as a turn.
3.3.4.6.4  The final phase of the missed approach is at the point where a clearance of 50 m (164
ft) can be maintained.
3.3.4.6.5  The missed approach obstacle clearances are shown on Figure A-3-1.

Missed approach – precision approach and APV

For precision approaches and APVs, an SOC is not defined. The decision altitude is always
established at a level that will accommodate height loss (see Table A-3-8). Therefore, the climb is
assumed to commence after the full height loss has occurred. These factors are “worst case” and
are subsumed by the design of the procedure’s assessment surfaces.

3.3.4.6

3.3.4.7

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Extracted from ICAO Document 8168, Volume III - First Edition - Procedures for Air Naviga-
tion Services - AIRCRAFT OPERATIONS, Flight Procedures, herein known as PANS-OPS.

INTRODUCTION TO ALTIMETER SETTING PROCEDURES

1.1 These procedures describe the method for providing adequate vertical separation between
aircraft and for providing adequate terrain clearance during all phases of a flight. This method is
based on the following basic principles:

a. States may specify a fixed altitude known as the transition altitude. In flight, when an aircraft

is at or below the transition altitude, its vertical position is expressed in terms of altitude,
which is determined from an altimeter set to sea level pressure (QNH).

b. In flight above the transition altitude, the vertical position of an aircraft is expressed in terms

of flight levels, which are surfaces of constant atmospheric pressure based on an altimeter
setting of 1013.2 hPa.

c. The change in reference from altitude to flight levels, and vice versa, is made:

1. at the transition

altitude, when climbing; and

2. at the transition

level, when descending.

d. The transition level may be nearly coincident with the transition altitude to maximize the

number of flight levels available. Alternatively, the transition level may be located 300 m (or
1000 ft) above the transition altitude to permit the transition altitude and the transition level to
be used concurrently in cruising flight, with vertical separation ensured. The airspace
between the transition level and the transition altitude is called the transition layer.

e. Where no transition altitude has been established for the area, aircraft in the en-route phase

shall be flown at a flight level.

f. The adequacy of terrain clearance during any phase of a flight may be maintained in any of

several ways, depending upon the facilities available in a particular area. The recommended
methods in the order of preference are:

1. the use of current QNH reports from an adequate network of QNH reporting stations;
2. the use of such QNH reports as are available, combined with other meteorological infor-

mation such as forecast lowest mean sea level pressure for the route or portions
thereof; and

3. where relevant current information is not available, the use of values of the lowest alti-

tudes or flight levels, derived from climatological data.

g. During the approach to land, terrain clearance may be determined by using:

1. the QNH altimeter setting (giving altitude); or
2. under specified circumstances a QFE setting (giving height above the QFE datum).

1.3 These procedures apply to all IFR flights and to other flights which are operating at specific
cruising levels in accordance with Annex 2 - Rules of the Air or the Procedures for Air Navigation

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Services - Air Traffic Management (PANS-ATM, Doc 4444) or the Regional Supplementary Pro-
cedures (Doc 7030).

BASIC ALTIMETER SETTING REQUIREMENTS

GENERAL

System of flight levels

2.1.1.1 Flight level zero shall be located at the atmospheric pressure level of 1013.2 hPa. Con-
secutive flight levels shall be separated by a pressure interval corresponding to at least 500 ft
(152.4 m) in the standard atmosphere.

Transition altitude

2.1.2.1  A transition altitude shall normally be specified for each aerodrome by the State in which
the aerodrome is located.
2.1.2.2  Where two or more closely spaced aerodromes are located so that coordinated proce-
dures are required, a common transition altitude shall be established. This common transition alti-
tude shall be the highest that would be required if the aerodromes were considered separately.
2.1.2.4  The height above the aerodrome of the transition altitude shall be as low as possible but
normally not less than 900 m (3000 ft).
2.1.2.5  The calculated height of the transition altitude shall be rounded up to the next full 300 m
(1000 ft).
2.1.2.7  Transition altitudes shall be published in aeronautical information publications and
shown on the appropriate charts.

Transition level

2.1.3.1 States shall make provision for the determination of the transition level to be used at any
given time at each of their aerodromes.
2.1.3.2 Where two or more closely spaced aerodromes are located so that coordinated proce-
dures and a common transition altitude are required, a common transition level shall also be used
at those aerodromes.

References to vertical position

2.1.4.1 The vertical position of aircraft operating at or below the transition altitude shall be
expressed in terms of altitude. Vertical position at or above the transition level shall be expressed
in terms of flight levels. This terminology applies during:

a. climb;
b. en-route flight; and

c. approach and landing

2.1.4.2 Passing through the transition layer
While passing through the transition layer, vertical position shall be expressed in terms of:

2.1

2.1.1

2.1.2

2.1.3

2.1.4

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a. flight levels when climbing; and
b. altitude when descending.

TAKE-OFF AND CLIMB

A QNH altimeter setting shall be made available to aircraft in taxi clearance prior to take-off.

EN-ROUTE

2.3.1 When complying with the specifications of Annex 2, an aircraft shall be flown at altitudes or
flight levels (as applicable) corresponding to the magnetic tracks shown in the table of cruising
levels in Appendix 3 to Annex 2.

Terrain clearance

2.3.2.1 QNH altimeter setting reports should be provided from sufficient locations to permit
determination of terrain clearance with an acceptable degree of accuracy.
2.3.2.2 For areas where adequate QNH altimeter setting reports cannot be provided, the appro-
priate authorities shall provide the information required to determine the lowest flight level which
will ensure adequate terrain clearance. This information shall be made available in the most
usable form.

APPROACH AND LANDING

2.4.1 The QNH altimeter setting shall be made available to aircraft in approach clearances and
in clearances to enter the traffic circuit.
2.4.2 A QFE altimeter setting, clearly identified as such, should be made available in approach
and landing clearances. This should be available on request or on a regular basis, in accordance
with local arrangements.

References to vertical positioning after approach clearance

After approach clearance has been issued and the descent to land is begun, the vertical position-
ing of an aircraft above the transition level may be by reference to altitudes (QNH) provided that
level flight above the transition altitude is not indicated or anticipated.

MISSED APPROACH

The relevant parts of 2.2, “Take-off and climb”, 2.3, “En-route”, and 2.4, “Approach and landing”
shall apply in the event of a missed approach.

PROCEDURES FOR OPERATORS AND PILOTS

FLIGHT PLANNING

3.1.1 The levels at which a flight is to be conducted shall be specified in a flight plan:

a. as flight levels if the flight is to be conducted at or above the transition level (or the lowest

usable flight level, if applicable); and

b. as altitudes if the flight is to be conducted at or below the transition altitude.

2.2

2.3

2.3.2

2.4

2.4.3

2.5

3.1

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3.1.2 The altitudes or flight levels selected for flight:

a. should ensure adequate terrain clearance at all points along the route;
b. should satisfy air traffic control requirements; and

c. should be compatible with the table of cruising levels in Appendix 3 to Annex 2, if relevant.

NOTE 1: The information required to determine the lowest altitude or flight level which ensures
adequate terrain clearance may be obtained from the appropriate services unit (e.g. aeronautical
information, air traffic or meteorological).
NOTE 2: The choice of altitudes or flight levels depends upon how accurately their vertical posi-
tion relative to the terrain can be estimated. This in turn depends upon the type of meteorological
information available. A lower altitude or flight level may be used with confidence when its position
is based on current information which is relevant to the particular route to be flown and when it is
known that amendments to this information will be available in flight. See 3.4.2, "Terrain clear-
ance". A higher altitude or flight level will be used when based on information less relevant to the
particular route to be flown and the time of the flight. The latter type of information may be provi-
ded in chart or table form and may be applicable to a large area and any period of time.
NOTE 3: Flights over level terrain may often be conducted at one altitude or flight level. On the
other hand, flights over mountainous terrain may require several changes in altitudes or flight
levels to account for changes in the elevation of the terrain. The use of several altitudes or flight
levels may also be required to comply with air traffic services requirements.

PRE-FLIGHT OPERATIONAL TEST

The following test should be carried out in an aircraft by flight crew members before flight. Flight
crews should be advised of the purpose of the test and the manner in which it should be carried
out. They should also be given specific instructions on the action to be taken based on the test
results.
QNH Setting

a. With the aircraft at a known elevation on the aerodrome, set the altimeter pressure scale to

the current QNH setting.

b. Vibrate the instrument by tapping unless mechanical vibration is provided. A serviceable

altimeter indicates the elevation of the point selected, plus the height of the altimeter above
this point, within a tolerance of:

1. ±20 m or 60 ft for altimeters with a test range of 0 to 9000 m (0 to 30000 ft); and
2. ±25 m or 80 ft for altimeters with a test range of 0 to 15000 m (0 to 50000 ft).

QFE Setting

a. With the aircraft at a known elevation on the aerodrome, set the altimeter pressure scale to

the current QFE setting.

3.2

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b. Vibrate the instrument by tapping unless mechanical vibration is provided. A serviceable

altimeter indicates the height of the altimeter in relation to the QFE reference point, within a
tolerance of:

1. ±20 m or 60 ft for altimeters with a test range of 0 to 9000 m (0 to 30000 ft); and
2. ±25 m or 80 ft for altimeters with a test range of 0 to 15000 m (0 to 50000 ft).

TAKE-OFF AND CLIMB

3.3.1  Before taking off, one altimeter shall be set on the latest QNH altimeter setting for the aer-
odrome.
3.3.2  During climb to, and while at the transition altitude, references to the vertical position of the
aircraft in air-ground communications shall be expressed in terms of altitudes.
3.3.3  On climbing through the transition altitude, the reference for the vertical position of the air-
craft shall be changed from altitudes (QNH) to flight levels (1013.2 hPa), and thereafter the verti-
cal position shall be expressed in terms of flight levels.

EN-ROUTE

Vertical separation

3.4.1.1 During en-route flight at or below the transition altitude, an aircraft shall be flown at alti-
tudes. References to the vertical position of the aircraft in air-ground communications shall be
expressed in terms of altitudes.
3.4.1.2 During en-route flight at or above transition levels or the lowest usable flight level, which-
ever is applicable, an aircraft shall be flown at flight levels. References to the vertical position of
the aircraft in air-ground-communications shall be expressed in terms of flight levels.

Terrain clearance

3.4.2.1 Where adequate QNH altimeter setting reports are available, the latest and most appro-
priate reports shall be used for assessing terrain clearance.
3.4.2.2 Where the adequacy of terrain clearance cannot be assessed with an acceptable degree
of accuracy by means of the QNH reports available or forecast lowest mean sea level pressure,
other information shall be obtained for checking the adequacy of terrain clearance.

APPROACH AND LANDING

3.5.1  Before beginning the initial approach to an aerodrome, the number of the transition level
shall be obtained.
3.5.2  Before descending below the transition level, the latest QNH altimeter setting for the aero-
drome shall be obtained.
3.5.3  As the aircraft descends through the transition level, the reference for the vertical position
of the aircraft shall be changed from flight levels (1013.2 hPa) to altitudes (QNH). From this point
on, the vertical position of the aircraft shall be expressed in terms of altitudes.

3.3

3.4

3.4.1

3.4.2

3.5

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3.5.4 When an aircraft which has been given a clearance as number one to land is completing
its approach using QFE, the vertical position of the aircraft shall be expressed in terms of the
height above the aerodrome datum which was used in establishing obstacle clearance height
(OCH). All subsequent references to vertical position shall be made in terms of height.

ALTIMETER CORRECTIONS

NOTE: This chapter deals with altimeter corrections for pressure, temperature and, where appro-
priate, wind and terrain effects. The pilot is responsible for these corrections except when under
radar vectoring. In that case, the radar controller issues clearances such that the prescribed
obstacle clearance will exist at all times, taking the cold temperature correction into account.

RESPONSIBILITY

Pilot's responsibility

The pilot-in-command is responsible for the safety of the operation and the safety of the aero-
plane and of all persons on board during flight time (Annex 6, 4.5.1). This includes responsibility
for obstacle clearance, except when an IFR flight is being vectored.

Operator's responsibility

The operator is responsible for establishing minimum flight altitudes, which may not be less than
those established by States that are flown over (Annex 6, 4.2.6). The operator is responsible for
specifying a method for determining these minimum altitudes (Annex 6, 4.2.6). Annex 6 recom-
mends that the method should be approved by the State of the Operator and also recommends
the factors to be taken into account.

State's responsibility

Annex 15, Appendix 1 (Contents of Aeronautical Information Publication), indicates that States
should publish in Section GEN 3.3.5, “The criteria used to determine minimum flight altitudes”. If
nothing is published, it should be assumed that no corrections have been applied by the State.

Air traffic control (ATC)

If an aircraft is cleared by ATC to an altitude which the pilot-in-command finds unacceptable due
to low temperature, then the pilot-in-command should request a higher altitude. If such a request
is not received, ATC will consider that the clearance has been accepted and will be complied with.

Flights outside controlled airspace

4.1.5.1 For IFR flights outside controlled airspace, including flights operating below the lower
limit of controlled airspace, the determination of the lowest usable flight level is the responsibility
of the pilot-in-command. Current or forecast QNH and temperature values should be taken into
account.
4.1.5.2 It is possible that altimeter corrections below controlled airspace may accumulate to the
point where the aircraft's position may impinge on a flight level or assigned altitude in controlled
airspace. The pilot-in-command must then obtain clearance from the appropriate control agency.

4.1

4.1.1

4.1.2

4.1.3

4.1.4

4.1.5

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PRESSURE CORRECTION

Flight levels

When flying at levels with the altimeter set to 1013.2 hPa, the minimum safe altitude must be cor-
rected for deviations in pressure when the pressure is lower than the standard atmosphere (1013
hPa). An appropriate correction is 10 m (30 ft) per hPa below 1013 hPa. Alternatively, the correc-
tion can be obtained from standard correction graphs or tables supplied by the operator.

QNH/QFE

When using the QNH or QFE altimeter setting (giving altitude or height above QFE datum respec-
tively), a pressure correction is not required.

TEMPERATURE CORRECTION

Requirement for temperature correction

The calculated minimum safe altitudes/heights must be adjusted when the ambient temperature
on the surface is much lower than that predicted by the standard atmosphere. In such conditions,
an approximate correction is 4 per cent height increase for every 10°C below standard tempera-
ture as measured at the altimeter setting source. This is safe for all altimeter setting source alti-
tudes for temperatures above -15°C.

Tabulated corrections

For colder temperatures, a more accurate correction should be obtained from Tables 2-4-1 a) and
2-4-1 b). These tables are calculated for a sea level aerodrome. They are therefore conservative
when applied at higher aerodromes.

Accurate corrections

4.3.4.1 For occasions when a more accurate temperature correction is required, this may be
obtained from Equation 24 of the Engineering Sciences Data Unit (ESDU) publication, Perform-
ance, Volume 2, Item Number 7702. This assumes an off-standard atmosphere.

where:

PAirplane

= aircraft height above aerodrome (pressure)

GAirplane

= aircraft height above aerodrome (geopotential)

std

= temperature deviation from the International Standard Atmosphere (ISA) temperature

= standard temperature lapse rate with pressure altitude in the first layer (sea level to tropo-

pause) of the ISA
t

= standard temperature at sea level

4.2

4.2.1

4.2.2

4.3

4.3.1

4.3.2

4.3.4

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Small corrections

For practical operational use, it is appropriate to apply a temperature correction when the value of
the correction exceeds 20 per cent of the associated minimum obstacle clearance (MOC).

MOUNTAINOUS AREAS – EN-ROUTE

The MOC over mountainous areas is normally applied during the design of routes and is stated in
State aeronautical information publications. However, where no information is available, the mar-
gins in Tables 2-4-2 and 2-4-3 may be used when:

a. the selected cruising altitude or flight level or one engine inoperative stabilizing altitude is at

or close to the calculated minimum safe altitude; and

b. the flight is within 19 km (10 NM) of terrain having a maximum elevation exceeding 900 m

(3000 ft).

MOUNTAINOUS TERRAIN - TERMINAL AREAS

4.5.1 The combination of strong winds and mountainous terrain can cause local changes in
atmospheric pressure due to the Bernoulli effect. This occurs particularly when the wind direction
is across mountain crests or ridges. It is not possible to make an exact calculation, but theoretical
studies (CFD Norway, Report 109.1989) have indicated altimeter errors as shown in Tables 2-4-4
and 2-4-5. Although States may provide guidance, it is up to the pilot-in-command to evaluate
whether the combination of terrain, wind strength and direction are such as to make a correction
for wind necessary.
4.5.2 Corrections for wind speed should be applied in addition to the standard corrections for
pressure and temperature, and ATC should be advised.

Table 2-4-1 a). Values to be added by the pilot to minimum promulgated heights/altitudes

(m)

Aerodrome

tempera-

ture (°C)

Height above the elevation of the altimeter setting source (metres)

120 150 180 210 240 270 300 450 600 900

120

150

–10

120 150

–20

130 170 215

–30

115 170 230 285

–40

110 145 220 290 365

–50

135 180 270 360 450

4.3.6

4.4

4.5

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Table 2-4-1 b). Values to be added by the pilot to minimum promulgated heights/altitudes

(ft)

Aerodrome

tempera-

ture (°C)

Height above the elevation of the altimeter setting source (feet)

200 300 400 500 600 700 800 900

100

150

200

300

400

500

120 170 230 280

–10

100 150 200 290 390 490

–20

100 120 130 140 210 280 420 570 710

–30

100 120 140 150 170 190 280 380 570 760 950

–40

100 120 150 170 190 220 240 360 480 720 970 121

–50

120 150 180 210 240 270 300 450 590 890 119

150

Table 2-4-2/3. Margin in mountainous areas

Terrain variation

MOC

Between 3000 ft and 5000 ft

(900 m and 1500 m)

1476 ft

(450 m)

Greater than 5000 ft

(1500 m)

1969 ft

(600 m)

Table 2-4-4/5. Altimeter error due to wind speed

Wind speed

Altimeter error

20 kt (37 km/h)

53 ft (17 m)

40 kt (74 km/h)

201 ft (62 m)

60 kt (111 km/h)

455 ft (139 m)

80 kt (148 km/h)

812 ft (247 m)

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Extracted from ICAO Document 8168, Volume III - First Edition - Procedures for Air Naviga-
tion Services - AIRCRAFT OPERATIONS, Flight Procedures, herein known as PANS-OPS.

MODES OF OPERATION

1.2.1 There can be a variety of modes of operation associated with the use of parallel or near-
parallel instrument runways.

Modes 1 and 2 - Simultaneous parallel instrument approaches

There are two basic modes of operation for approaches made to parallel runways:

a. Mode 1, Independent parallel approaches: In this mode, radar separation minima between

aircraft using adjacent ILS and/or MLS are not prescribed; and

b. Mode 2, Dependent parallel approaches: In this mode, radar separation minima between air-

craft using adjacent ILS and/or MLS are prescribed.

Mode 3 - Simultaneous instrument departures

Mode 3, Independent parallel departures: In this mode, aircraft are departing in the same direction
from parallel runways simultaneously.

Mode 4 - Segregated parallel approaches/departures

Mode 4, Segregated parallel operations: In this mode, one runway is used for approaches, and
one runway is used for departures.

Semi-mixed and mixed operations

1.2.1.4.1 In the case of parallel approaches and departures, there may be semi-mixed opera-
tions. In this scenario:

a. one runway is used exclusively for departures, while the other runway accepts a mixture of

approaches and departures; or

b. one runway is used exclusively for approaches while the other runway accepts a mixture of

approaches and departures.

1.2.1.4.2 There may also be mixed operations, i.e. simultaneous parallel approaches with
departures interspersed on both runways.

OPERATIONAL APPROVAL

Aircraft Eligibility

1.3.1.1 An aircraft may be utilized for parallel operations if:

a. for operations utilizing a precision approach, the aircraft has the relevant precision approach

capability; and

1.2

1.2.1.1

1.2.1.2

1.2.1.3

1.2.1.4

1.3

1.3.1

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b. for operations utilizing a PBN approach, the aircraft meets the eligibility requirements for the

particular navigation specification used in the design of the procedures.

NOTE: More information on aircraft eligibility for navigation specification is contained in the Per-
formance-based Navigation (PBN) Manual (Doc 9613).

PARALLEL APPROACH OPERATIONS

Independent/dependent parallel approaches operations may be conducted using any combination
of three-dimensional (3D) instrument approach operations provided that:

a. instrument approach charts are available that contain operational notes regarding the paral-

lel approach procedures;

b. aircraft are advised as early as possible of the assigned runway, instrument approach proce-

dures and any additional information considered necessary to confirm correct selection;

c. the final approach course or track is intercepted by use of:

1. vectoring; or
2. a published arrival and approach procedure that intercepts with the IAF or IF;

d. as early as practicable after an aircraft has established communication with approach con-

trol, the aircraft is advised that independent parallel approaches are in force. This information
may be provided through the automatic terminal information service (ATIS) broadcasts. In
addition, the aircraft shall be advised of the runway identification and the ILS localizer and/or
MLS frequency to be used; and

e. dedicated radio channels or override capability for the monitoring controllers to use for the

appropriate voice communication facilities are provided.

NOTE: Refer to Procedures for Air Navigation Services — Air Traffic Management (PANS-ATM,
Doc 4444), Chapter 6 for further detail.

INTERCEPTING THE FINAL APPROACH COURSE OR TRACK

1.5.1 When simultaneous independent parallel approaches are in progress, the following apply:

a. the main objective is that both aircraft be established on the approved instrument approach

procedure final approach course or track before the 300 m (1000 ft) vertical separation is
reduced;

b. all approaches, regardless of weather conditions, will be monitored using an ATS surveil-

lance system. Control instructions and information to ensure separation between aircraft and
to ensure that aircraft do not enter the NTZ will be issued as necessary. The air traffic control
procedure will be to either vector arriving aircraft or use an arrival or approach procedure to
position the aircraft for an intercept of one or the other of the parallel approach courses or
tracks. When cleared for an ILS or MLS approach, a procedure turn is not permitted;

c. when vectoring to intercept the final approach course or track, the final vector will meet the

following conditions:

1.4

1.5

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1. enable the aircraft to intercept at an angle not greater than 30 degrees;
2. provide at least 1.9 km (1.0 NM) straight and level flight prior to the final approach

course or track intercept; and

3. enable the aircraft to be established on the final approach course or track, in level flight

for at least 3.7 km (2.0 NM) prior to intercepting the glide path or vertical path for the
selected instrument approach procedure;

d. the published arrival or approach procedure used to position the aircraft for an intercept of

the final course or track will be designed in accordance with the procedures detailed in
PANS-OPS, Volume II, Part II, Section 1, with specific reference to simultaneous
approaches to parallel or near-parallel instrument runways;

e. each pair of parallel approaches will have a “high side” and a “low side” for positioning air-

craft to provide vertical separation until aircraft are established inbound on their respective
parallel final approach course or track. The low side altitude will normally be such that the
aircraft will be established on the final approach course or track well before glide path or ver-
tical path interception. The high side altitude will be 300 m (1000 ft) above the low side.
NOTE: The application of vertical separation may be discontinued after the initial approach
fix (IAF) or intermediate approach fix (IF) when an aircraft is established on an RNP AR
APCH procedure, in accordance with the provisions in the Procedures for Air Navigation
Services — Air Traffic Management (PANS-ATM Doc 4444), Chapter 6.

f. when the aircraft is assigned its final heading to intercept the final approach course or track,

it will be advised of:

1. the altitude to be maintained until:

(a) the aircraft is established on the final approach course or track; and
(b) the aircraft has reached the glide path or vertical path intercept point; and

2. if required, clearance for the final approach;

g. if an aircraft is observed to overshoot the turn-to-final or to continue on a track which will

penetrate the NTZ, the aircraft will be instructed to return immediately to the correct track.
Pilots are not required to acknowledge these transmissions or subsequent instructions while
on final approach unless requested to do so;

h. once the 300 m (1000 ft) vertical separation is reduced, the controller monitoring the

approach will issue control instructions if the aircraft deviates substantially from the final
approach course or track;

i. if an aircraft that deviates substantially from the final approach course or track fails to take

corrective action and penetrates the NTZ, the aircraft on the adjacent final approach course
or track will be instructed to immediately climb and turn to the assigned altitude and heading
in order to avoid the deviating aircraft.

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Extracted from ICAO Document 8168, Volume III - First Edition - Procedures for Air Naviga-
tion Services - AIRCRAFT OPERATIONS, Flight Procedures, herein known as PANS-OPS.

OPERATION OF TRANSPONDERS

GENERAL

1.1.1  When an aircraft carries a serviceable transponder, the pilot shall operate the transponder
at all times during flight, regardless of whether the aircraft is within or outside airspace where sec-
ondary surveillance radar (SSR) is used for ATS purposes.
1.1.3  When the aircraft carries serviceable Mode C equipment, the pilot shall continuously oper-
ate this mode, unless otherwise directed by ATC.
1.1.5  When requested by ATC to “CONFIRM SQUAWK [code]” the pilot shall:

a. verify the Mode A code setting on the transponder;
b. reselect the assigned code if necessary; and

c. confirm to ATC the setting displayed on the controls of the transponder.

1.1.6 Pilots shall not SQUAWK IDENT unless requested by ATC.

USE OF MODE C

Whenever Mode C is operated, pilots shall, in air-ground voice communications where level infor-
mation is required, give such information by stating their level to the nearest full 30 m or 100 ft as
indicated on the pilot’s altimeter.

USE OF MODE S

Pilots of aircraft equipped with Mode S having an aircraft identification feature shall set the aircraft
identification in the transponder. This setting shall correspond to the aircraft identification speci-
fied in item 7 of the ICAO flight plan, or, if no flight plan has been filed, the aircraft registration.

EMERGENCY PROCEDURES

The pilot of an aircraft in a state of emergency shall set the transponder to Mode A Code 7700
unless ATC has previously directed the pilot to operate the transponder on a specified code. In
the latter case, the pilot shall continue to use the specified code unless otherwise advised by
ATC. However, a pilot may select Mode A Code 7700 whenever there is a specific reason to
believe that this would be the best course of action.

COMMUNICATION FAILURE PROCEDURES

The pilot of an aircraft losing two-way communications shall set the transponder to Mode A Code
7600.
NOTE: A controller who observes an SSR response indicating selection of the communications
failure code will determine the extent of the failure by instructing the pilot to SQUAWK IDENT or
to change code. If it is determined that the aircraft receiver is functioning, further control of the
aircraft will be continued using code changes or IDENT transmission to acknowledge receipt of

1.1

1.2

1.3

1.4

1.5

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clearances. Different procedures may be applied to Mode S equipped aircraft in areas of Mode S
coverage.

UNLAWFUL INTERFERENCE WITH AIRCRAFT IN FLIGHT

1.6.1 If there is unlawful interference with an aircraft in flight, the pilot-in-command shall attempt
to set the transponder to Mode A Code 7500 in order to indicate the situation. If circumstances so
warrant, Code 7700 should be used instead.
1.6.2 If a pilot has selected Mode A Code 7500 and has been requested to confirm this code by
ATC (in accordance with 1.1.5), the pilot shall, according to circumstances, either confirm this or
not reply at all.
NOTE: If the pilot does not reply, ATC will take this as confirmation that the use of Code 7500 is
not an inadvertent false code selection.

TRANSPONDER FAILURE PROCEDURES WHEN THE CARRIAGE OF A

FUNCTIONING TRANSPONDER IS MANDATORY

1.7.1 In case of a transponder failure after departure, ATC units shall attempt to provide for con-
tinuation of the flight to the destination aerodrome in accordance with the flight plan. Pilots may,
however, expect to comply with specific restrictions.

PHRASEOLOGY

PHRASEOLOGY USED BY PILOTS

Pilots shall read back the mode and code to be set when they acknowledge mode/code setting
instructions.

OPERATION OF AIRBORNE COLLISION AVOIDANCE

SYSTEM (ACAS) EQUIPMENT

3.1.1  The information provided by an ACAS is intended to assist pilots in the safe operation of
aircraft by providing advice on appropriate action to reduce the risk of collision. This is achieved
through resolution advisories (RAs), which propose manoeuvres, and through traffic advisories
(TAs), which are intended to prompt visual acquisition and to act as a warning that an RA may
follow. TAs indicate the approximate positions of intruding aircraft that may later cause resolution
advisories. RAs propose vertical manoeuvres that are predicted to increase or maintain separa-
tion from threatening aircraft. ACAS I equipment is only capable of providing TAs, while ACAS II
is capable of providing both TAs and RAs. In this chapter, reference to ACAS means ACAS II.
3.1.2  ACAS indications shall be used by pilots in the avoidance of potential collisions, the
enhancement of situational awareness, and the active search for, and visual acquisition of, con-
flicting traffic.
3.1.3  Nothing in the procedures specified in 3.2 hereunder shall prevent pilots-in-command from
exercising their best judgment and full authority in the choice of the best course of action to
resolve a traffic conflict or avert a potential collision.

1.6

1.7

2.2

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USE OF ACAS INDICATIONS

The indications generated by ACAS shall be used by pilots in conformity with the following safety
considerations:

a. pilots shall not maneuver their aircraft in response to traffic advisories (TAs) only;
b. on receipt of a TA, pilots shall use all available information to prepare for appropriate action if

an RA occurs; and

c. in the event of an RA, pilots shall:

1. respond immediately by following the RA as indicated, unless doing so would jeopard-

ize the safety of the aeroplane;
NOTE 1: Stall warning, wind shear, and ground proximity warning system alerts have
precedence over ACAS.
NOTE 2: Visually acquired traffic may not be the same traffic causing an RA. Visual per-
ception of an encounter may be misleading, particularly at night.

2. follow the RA even if there is a conflict between the RA and an air traffic control (ATC)

instruction to manoeuvre;

3. not manoeuvre in the opposite sense to an RA;

NOTE: In the case of an ACAS-ACAS coordinated encounter, the RAs complement
each other in order to reduce the potential for collision. Manoeuvres, or lack of manoeu-
vres, that result in vertical rates opposite to the sense of an RA could result in a collision
with the intruder aircraft.

4. as soon as possible, as permitted by flight crew workload, notify the appropriate ATC

unit of any RA which requires a deviation from the current ATC instruction or clearance;
NOTE: Unless informed by the pilot, ATC does not know when ACAS issues RAs. It is
possible for ATC to issue instructions that are unknowingly contrary to ACAS RA indica-
tions. Therefore, it is important that ATC be notified when an ATC instruction or clear-
ance is not being followed because it conflicts with an RA.

5. promptly comply with any modified RAs;
6. limit the alterations of the flight path to the minimum extent necessary to comply with

the RAs;

7. promptly return to the terms of the ATC instruction or clearance when the conflict is

resolved; and

8. notify ATC when returning to the current clearance.

NOTE 1: Procedures in regard to ACAS-equipped aircraft and the phraseology to be used
for the notification of manoeuvres in response to a resolution advisory are contained in the
PANS-ATM (Doc 4444), Chapters 15 and 12 respectively.

3.2

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NOTE 2: Where aircraft can provide automatic following of an RA when the autopilot is
engaged supported by a link between ACAS and autopilot, the operational procedures in
items 4) and 8) still apply.

HIGH VERTICAL RATE (HVR) ENCOUNTERS

Pilots should use appropriate procedures by which an aeroplane climbing or descending to an
assigned altitude or flight level, especially with an autopilot engaged, may do so at a rate less
than 8 m/s (or 1500 ft/min) throughout the last 300 m (or 1000 ft) of climb or descent to the
assigned altitude or flight level when the pilot is made aware of another aircraft at or approaching
an adjacent altitude or flight level, unless otherwise instructed by ATC. Some aircraft have auto-
flight systems with the capability to detect the presence of such aircraft and adjust their vertical
rate accordingly. These procedures are intended to avoid unnecessary ACAS II resolution adviso-
ries in aircraft at or approaching adjacent altitudes or flight levels. For commercial operations,
these procedures should be specified by the operator.

3.3

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Extracted from ICAO Document 8168, Volume III - First Edition - Procedures for Air Naviga-
tion Services - AIRCRAFT OPERATIONS, Flight Procedures, herein known as PANS-OPS.

AERODROME SURFACE OPERATIONS

1.1 Operators shall develop and implement standard operating procedures (SOPs) for aero-
drome surface operations. The development and implementation of SOPs shall take into consid-
eration the risk factors (listed in 1.3) associated with the following operations:

a. runway intersection take-offs;
b. line-up and wait clearances;

c. land and hold-short clearances;

d. take-offs from displaced runway thresholds;
e. hazards associated with runway crossing traffic;

f. hazards associated with runway crossing traffic in the case of closely spaced parallel run-

ways; and

g. hazards associated with the risk of collision at hot spot locations on aerodromes.

1.3 Operators should ensure that flight personnel are aware of the risk factors in the aerodrome
surface operations listed in 1.1. Such risk factors should include, but not be limited to:

a. human error due to excessive workload, loss of vigilance and fatigue;
b. potential distractions associated with the performance of flight deck tasks; and

c. failure to use standard phraseology in aeronautical communications.

NOTE: The safety of aerodrome surface operations is especially vulnerable to the failure to use
standard phraseology in aeronautical communications. Frequency congestion, as well as opera-
tional considerations, may adversely affect the issuance and read-back of clearances, leaving
flight crews' and controllers vulnerable to misunderstandings.

READ-BACK OF CLEARANCES AND SAFETY-RELATED

INFORMATION

NOTE: Provisions on read-back of clearances and safety-related information are included in
Annex 11, Chapter 3, 3.7.3, and in the PANS-ATM (Doc 4444), Chapter 4.

STABILIZED APPROACH PROCEDURE

GENERAL

The primary safety consideration in the development of the stabilized approach procedure shall
be maintenance of the intended flight path as depicted in the published approach procedure, with-
out excessive manoeuvring. The parameters to be considered in the definition of a stabilized
approach are listed in 3.2.

3.1

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PARAMETERS FOR THE STABILIZED APPROACH

The parameters for the stabilized approach shall be defined by the operator’s standard operating
procedures (SOPs). These parameters shall be included in the operator’s operations manual and
shall provide details regarding at least the following:

a. range of speeds specific to each aircraft type;
b. minimum power setting(s) specific to each aircraft type;

c. range of attitudes specific to each aircraft type;

d. crossing altitude deviation tolerances;
e. configuration(s) specific to each aircraft type;

f. maximum sink rate; and

g. completion of checklists and crew briefings.

ELEMENTS OF THE STABILIZED APPROACH

The elements of a stabilized approach (according to the parameters in 3.2) shall be stated in the
operator’s SOPs. These elements should include as a minimum:

a. that in instrument meteorological conditions (IMC), all flights shall be stabilized by no lower

than 300 m (1000 ft) height above threshold; and

b. that all flights of any nature shall be stabilized by no lower than 150 m (500 ft) height above

threshold.

GO-AROUND POLICY

Standard operating procedures should include the operator's policy with regard to the parameters
in 3.2 and the elements in 3.3. This policy should state that if an approach is not stabilized in
accordance with 3.3, or has become destabilized at any subsequent point during an approach, a
go-around is required. Operators should reinforce this policy through training.

REDUCED POWER TAKE-OFF

Reduced power take-off should not be required in adverse operating conditions such as:

a. if the runway surface conditions are adversely affected (e.g. by snow, slush, ice, water, mud,

rubber, oil or other substances);

b. when the horizontal visibility is less than 1.9 km (1 NM);

c. when the crosswind component, including gusts, exceeds 28 km/h (15 kt);

d. when the tailwind component, including gusts, exceeds 9 km/h (5 kt); and
e. when wind shear has been reported or forecast or when thunderstorms are expected to

affect the approach or departure.

NOTE: Some operating manuals (or the flight manual) may impose restrictions on the use of
reduced take-off power while engine anti-icing systems are operating.

3.2

3.3

3.4

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JEPPESEN GENERAL AIRWAY MANUAL (Issue Date 1 JUL 21) - page 34