Explanatory Statement
Civil Aviation Safety Regulations 1998
Manual of Standards Part 139 Amendment (No. 1) 2011
Purpose
The purpose of Manual of Standards Part 139 Amendment (No. 1) 2011 (the MOS amendment) is to introduce aerodrome marking, lighting and operational procedures for supporting aircraft conducting low visibility operations.
Legislation
Section 98 (1) of the Civil Aviation Act 1988 (the Act) provides that the Governor-General may make regulations for the purposes of the Act and in the interests of the safety of air navigation.
Some of these regulations are contained in the Civil Aviation Safety Regulations 1998 (CASR 1998). In particular, Part 139 of CASR 1998 deals with the operation of aerodromes, including rules about the certification of aerodromes and the requirements that apply to the operators of certified aerodromes.
Under regulation 139.015 of CASR 1998, the standards for aerodromes are those set out in the Manual of Standards Part 139 — Aerodromes (the MOS). The MOS contains mandatory standards for the facilities and equipment that aerodromes must have.
Related instruments
The MOS amendment amends the MOS. It is 1 of a package of 4 interrelated instruments dealing with low visibility operations arising from the same background, the other 3 being a determination of meteorological minima, a MOS Part 172 amendment and a MOS Part 173 amendment.
Background
In October 2007, CASA commenced Project AS 07/13 – Regulation of Low Visibility Operations. The objective of the project was to develop appropriate requirements and guidelines for the conduct in Australia of aircraft operations in conditions of reduced cloud ceiling or low visibility. The project reviewed local and international standards, consulted with industry and made recommendations for developing safe standards for low visibility operations.
Discussion Paper 0805AS – Low Visibility Operations in Australia (the DP) was published on 4 August 2008. It introduced 28 proposals covering aircraft operations, aerodrome and air traffic control (ATC) operations, instrument flight procedure design, aeronautical information services, and associated CASA approval processes. Significant proposals included:
- alignment of flight operational requirements (aerodrome infrastructure like lighting and markings) with standards for such infrastructure
- raising the existing take-off visibility minimum for aircraft at non-controlled aerodromes from 500 m to 800 m but with the provision for operators to take off in visibility conditions of not less than 550 m in certain circumstances.
- establishing the International Civil Aviation Organization (ICAO)-conforming Precision Approach Category II and Category III minima for use at suitably equipped aerodromes by approved aircraft operators
- adopting a number of ICAO standards for aerodrome infrastructure for low visibility operations.
Following consultations on the DP, on 12 December 2009 CASA released Notice of Proposed Rule Making (NPRM) 0906AS – IFR minima and low visibility operations (the NPRM). The NPRM formally notified CASA’s intention to implement the majority of the proposals introduced by the DP, including:
- aligning aircraft operational approvals and aerodrome infrastructure requirements around trigger visibility criteria of 800 m, 550 m and 350 m.
- for future CASRs relating to air transport operations (such as Parts 121, 133 and 135), amending the existing proposal for approach bans so that:
- the approach ban ‘limit’ would be standardised, for both precision and non‑precision approaches, at the point the aircraft descends through 1 000 ft above aerodrome level; and
- a runway visibility (RV) assessment, in addition to a runway visual range (RVR) or meteorological visibility report, may be used by a pilot to make the decision to continue or discontinue an approach
- adopting the revised ICAO visibility minima for Precision Approach Categories II, IIIA and IIIB
- establishing closer alignment between Australian aerodrome infrastructure requirements and ICAO Standards and Recommended Practices (SARPs) with respect to operations in visibility conditions of less than 800 m
- permitting approach light systems with either distance coded centreline or Barrette centreline configurations, as detailed in ICAO Annex 14 — Aerodromes
- adopting ICAO standards for runway touchdown zone markings and aiming point markings
- promulgating a Civil Aviation Advisory Publication (CAAP) to assist aircraft operators in applying for permission to conduct low visibility operations.
CASA received 10 responses to the NPRM and, in general, the proposals received a favourable response. The next step in the amendment process was the authorisation of changes to the relevant legislative documents. This Explanatory Statement covers changes to Manual of Standards (MOS) — Part 139.
Key features of specific changes in the MOS amendment and their impact
A General
Apart from the new standards for RV assessments (as described later in this Explanatory Statement), all the changes made in the MOS amendment adopt ICAO SARPs relevant to operations in conditions of reduced cloud ceiling or low visibility.
B Aerodrome operators to provide additional information on aerodrome lighting
The existing requirement for an aerodrome operator to publish information on various components of aerodrome infrastructure is amended to require additional information. In particular, aerodrome operators will be required to arrange for the following information to be published in the Aeronautical Information Publication (AIP):
(a) the type, length and intensity of the approach lighting system;
(b) the type, length, colour and intensity of various components of runway lighting;
(c) details of the procedures used at the aerodrome for supporting aircraft operations during conditions of reduced cloud ceiling or low visibility.
The new requirements mentioned in this section come into effect on 17 November 2011.
Impact
This change implements an existing ICAO standard for aeronautical information as detailed in Annex 15 to the International Convention on International Civil Aviation (the Chicago Convention). No significant impact is expected on aerodrome operators because the required information should already be known to the aerodrome operators. The additional information is essential for planning and conducting aircraft operations at aerodromes during conditions of reduced cloud ceiling or low visibility. The requirements are already in place in many other countries.
C New aiming point and touchdown zone markings
A new standard is introduced to implement Annex 14 (Aerodromes) to the Chicago Convention (Annex 14) standards for aiming point and touchdown zone markings on runways intended for precision approach operations. Aiming point and touchdown zone markings are a pattern of rectangles painted in white on the surface of a relevant runway intended to enhance pilot situation awareness during landing.
Previously, Australia used a unique form of aiming point (known as a fixed distance marking) and unique touchdown zone markings that differed significantly from the international standard. The intention of the new standard is for pilots (particularly those involved in international operations) to be presented with a consistent and familiar visual perspective when approaching a runway in conditions of reduced cloud ceiling or low visibility.
The standards mentioned in this section come into effect on 2 June 2011.
Impact
The cost of implementing the new standard for touchdown zone and aiming point markings for instrument runways is expected to be low. However, regardless of the cost, the safety benefits of the new standard, particularly during operations in conditions of reduced cloud ceiling or low visibility, make the changes imperative for safety reasons. The markings on a total of 19 runways (spread among 15 Australian aerodromes) will need to be modified under the new standard.
To minimise the impact, the chosen pattern allows aerodrome operators to utilise elements of the existing runway markings. In addition, mandatory compliance with the new standard will only come into effect on:
- 30 May 2013, for operators of aerodromes that support international flight operations
- 29 May 2014, for operators of other affected aerodromes.
These dates also coincide with the dates for planned relevant amendments to the AIP.
Aerodrome markings require routine maintenance, including repainting. The pattern selected and phased implementation period is intended to reduce the cost of implementation by allowing the new standard to be adopted as part of routine maintenance.
D Sunset provision for aerodromes not complying with MOS Part 139 standards
When MOS Part 139 came into effect in 2003, it introduced a number of changes to existing Australian aerodrome standards to align with ICAO Annex 14 standards and recommended practices. To reduce the impact on aerodrome operators, particularly the high cost of implementing ICAO-compliant aerodrome lighting systems, MOS Part 139 included a provision that exempted existing lighting facilities from compliance with the MOS until specified events occurred. These events included:
(a) the light fittings of a lighting system being replaced with fittings of a different type; and
(b) the facility being upgraded; and
(c) there being a change in the category of either:
(i) aerodrome layout; or
(ii) aerodrome traffic density; and
(d) in exceptional circumstances, CASA determining that, in the interest of safety, a lighting facility had to meet the standards of the MOS.
However, an unforseen outcome of the exemption provision is that aerodromes at which low visibility operations take place are not compelled to ensure lighting facilities meet the MOS Part 139 standards for operations in conditions of reduced cloud ceiling or low visibility. Low visibility operations are among the most complex and error-prone activities that can occur on an aerodrome. The worst aviation disasters have occurred in such conditions.
Standardisation of procedures and facilities is an important safety mitigator of risks during low visibility operations. To close the loophole and ensure appropriate standardisation of lighting facilities for low visibility operations, ‘support of low visibility operations’ is introduced as an event for requiring compliance with MOS Part 139 requirements.
The standards mentioned in this section come into effect on and from 2 June 2011 for an aerodrome operator who elects to be bound and notifies CASA. Otherwise, compliance following a trigger event becomes mandatory on and from 29 May 2014.
Impact
The costs of equipping an aerodrome for low visibility operations can be very high. However, the new trigger event does not compel any aerodrome to meet a specific capability. Instead, aerodrome operators are given 3 years to determine an appropriate level of capability for their aerodrome and either voluntarily elect to implement the necessary infrastructure, or set in place operating limits appropriate to the aerodrome’s facilities. Accordingly, CASA assesses the impact of the change as low.
E Approach lighting systems
A new standard is introduced which allows an additional pattern of approach lighting system as specified in Annex 14. An approach lighting system is an array of lights located on the approaches to precision approach runways. They are intended to assist pilots to gain visual contact with the runway environment during the conduct of instrument approaches in poor weather conditions.
Previously, Australia only permitted the use of 1 pattern of approach lighting system known as the ‘Calvert’ system. The new standard permits the use of both the ‘Calvert’ system and a pattern known as a ‘Barrette centreline pattern’.
The standards mentioned in this section come into effect on 2 June 2011.
Impact
CASA’s assessment is that the new standard for approach lighting systems will have no adverse impact on aerodrome operators. A positive impact of the new standards arises from the fact that the ‘Barrette centreline pattern’ uses a smaller land ‘footprint’ than the ‘Calvert’ system, and can be cheaper to install and maintain. The reduced environmental footprint and cost of the ‘Barrette centreline pattern’ systems may enable more runways to be equipped with approach lighting, leading to economic and safety benefits through lower minima (for example, continued operations in reduced weather conditions) and improved visual guidance to aircraft on approach.
F Serviceability levels for lighting
A new standard is introduced for the minimum acceptable serviceability level for lighting systems on a runway intended for precision approach Category II and III operations, a runway meant for take-off in visibility conditions of less than 550 m; and a taxiway intended for use in RVR conditions of less than 350 m. Precision approach Categories II and III operations are aircraft approach and landing operations in weather conditions as poor as a cloud ceiling of zero feet and a visibility as low as 75 m. The new standard is consistent with ICAO Annex 14 standards and recommended practices.
The standards mentioned in this section come into effect on 2 June 2011.
Impact
No significant impact is expected on aerodrome operators because the new standard is broadly similar to the existing standards for serviceability of various aerodrome lighting facilities.
G Aerodrome safety procedures during conditions of reduced visibility or low cloud
A new set of standards is introduced for the procedures for use by aerodrome operations personnel during conditions of reduced cloud ceiling or low visibility. An aerodrome operator will need to develop appropriate procedures that address specified topics mentioned in the MOS, apply these procedures under specified weather conditions, and periodically review the procedures to ensure they are fit for purpose. The standards are consistent with ICAO standards and recommended practices.
The standards mentioned in this section come into effect on 17 November 2011.
Impact
The impact of the new standards are expected to be low because all aerodromes with a local ATC tower are already required to have procedures for use in low visibility conditions. The new standards differ from the existing standards in that they provide more guidance for ensuring essential safety aspects are addressed. This is intended to achieve greater standardisation between Australian aerodromes and between Australian and international practice.
H Runway Visibility Assessments by Ground Personnel
A new set of standards is introduced relating to the training, appointment and duties for a person conducting RV assessments. As its name implies, an RV assessment is an assessment of the visibility along a particular runway taken from specific points. Information about the visibility along a runway is important for aircraft operations, particularly in marginal weather conditions. Previously, there were no standards for ensuring consistency and accuracy of RV assessments and procedures would vary from aerodrome to aerodrome. The general international practice is for the visibility along the runway to be measured by electronic systems which then present an RVR. The cost of RVR equipment has meant only 2 Australian aerodromes have installed RVR sensors and the remainder rely on RV assessment. To ensure standardisation and consistent RV practices, the RV assessment system from Canada has been adopted. The Canadian system was selected because it is a system proven in adverse weather conditions and is relatively easy to implement in the Australian operational environment.
The standards mentioned in this section come into effect on 17 November 2011.
Impact
The impact of the new standards is expected to be low, because existing RV assessment practices generally comply with most of the new standards, and will require only minor documentation and procedural changes.
I Siting of equipment and installations on operational areas
Several changes and new standards are introduced relating to the safeguarding of runway environments and navigation equipment installations. Among other things, the standards detail minimum distances that people, vehicles, aircraft and non-essential equipment must be kept away from runways and navigation equipment installations. The changes adopt ICAO Annex 14 SARPs in this regard.
The standards mentioned in this section come into effect on 2 June 2011.
Impact
The impact of the new standards is expected to be low because the existing practices are generally consistent with the proposed changes and only minor procedural changes will be necessary.
MOS amendment
Details of the MOS amendment are contained in Attachment 1.
Legislative Instruments Act
Under section 5 of the Legislative Instruments Act 2003 (the LIA), the MOS amendment is taken to be a legislative instrument because it is of a legislative character and satisfies the other attributes mentioned in section 5. As a legislative instrument, the MOS amendment is subject to registration, and tabling and disallowance in the Parliament, under sections 24, 38 and 42 of the LIA.
Consultation
Consultation under section 17 of the LIA has taken place under the NPRM process described above and in accordance with the requirements for making a MOS under Subpart 11.J of CASR 1998.
As noted, NPRM 0906AS – IFR minima and low visibility operations – was released for public consultation on 12 December 2009. The period for comment closed on 12 February 2010. There were 10 responses to the NPRM and CASA took each response into account in deciding how to proceed further with the NPRM.
Office of Best Practice Regulation (the OBPR)
CASA assessed the proposed changes for their impact on industry, and concluded that all the changes are expected to have a nil to low impact. CASA also submitted the change proposals for review by the OBPR, and has been informed that no Regulation Impact Statement is required (OBPR Exemption 10996 refers).
Making, commencement and date of effect
The MOS amendment has 2 commencement dates, 2 June 2011 for Schedule 1 amendments and 17 November 2011 for Schedule 2 amendments. Implementation is delayed to allow the procedural changes to be incorporated in the Aeronautical Information Publication at the internationally recognised amendment dates, and to give aerodrome operators some lead time to implement the necessary changes.
Specific amendments have a 2 or 3-year implementation lead time.
The MOS amendment has been made by the Director of Aviation Safety, on behalf of CASA, in accordance with subsection 73 (2) of the Act.
[Manual of Standards Part 139 Amendment (No. 1) 2011]
Attachment 1
Manual of Standards Part 139 Amendment (No. 1) 2011
1 Name of instrument
Under this section, the instrument is named the Manual of Standards Part 139 Amendment Instrument (No. 1) 2011.
2 Commencement
Under this section, the instrument commences as follows.
(a) on 2 June 2011 for sections 1, 2 and 3, and for Schedule 1;
(b) on 17 November 2011 for Schedule 2.
3 Amendment of the Manual of Standards Part 139
Under this section, Schedule 1 amends Manual of Standards Part 139.
Schedule 1 Amendments
[1] Section 1.2, definition of Instrument runway
This amendment updates the visibility values for precision approach runway Category (CAT) II from 350 m to 300 m; precision approach runway CAT IIIA from 200 m to 175 m; and precision approach runway CAT IIIB from 200 m to 175 m. This is to match the latest ICAO standards.
[2] Section 1.2, definition of Runway visual range (RVR)
This amendment amends the definition by adding a note explaining that within Australia, the term runway visual range (RVR) is used exclusively in relation to RVR measured by an instrumented system.
[3] Section 1.2, new definitions
This amendment adds the following definitions:
- Low visibility procedures: Procedures applied at an aerodrome for protecting aircraft operations during conditions of reduced visibility or low cloud.
- Runway visibility (RV): The distance along a runway over which a person can see and recognise a visibility marker or runway lights.
- Visibility marker: A dark object of suitable dimensions for use as a reference in evaluating runway visibility.
[4] After paragraph 6.2.24.2
This amendment inserts a requirement for mobile objects (such as personnel, vehicles and aircraft) to be kept a specified distance from a runway being used for landing or take off. The distance depends on the size of the aircraft making the landing or take-off, but varies between 45 and 77.5 metres from the runway centreline.
[5] After paragraph 6.2.28.1
Subsection 6.2.28 relates to runway end safety areas (RESA) — a type of prepared surface on an aerodrome. This amendment inserts a note advising readers of the subsection to also consider the information in subsection 11.1.4A regarding siting of equipment and installations on RESA.
[6] After paragraph 6.2.34.1
Subsection 6.2.34 relates to clearways — a type of prepared surface on an aerodrome. This amendment inserts a note advising readers of the subsection to also consider the information in subsection 11.1.4A regarding siting of equipment and installations on clearways.
[7] After paragraph 6.3.15.1
Subsection 6.3.15 relates to taxiway strips — a type of prepared surface on an aerodrome. This amendment inserts a note advising readers of the subsection to also consider the information in subsection 11.1.4A regarding siting of equipment and installations on taxiway strips.
[8] Paragraph 6.3.17.1, Table 6.3-5, after the second Note
This amendment inserts a note at the end of the table detailing taxiway minimum separation distance advising readers that ILS installations may also influence the location of taxiways due to interferences to ILS signals by a taxiing or stopped aircraft.
[9] Paragraph 6.4.4.2
This amendment omits the paragraph because the original standard has been moved to the end of Table 6.4-1. This is an editorial amendment to make this part of MOS Part 139 consistent with ICAO Annex 14.
[10] Paragraph 6.4.4.2, Table 6.4-1, Column 4, Precision Category I
This amendment adds the superscripted letters ‘e’ and ‘f’ to the distance values mentioned in the column ‘Category I’. These letters are a cross‑reference link to footnotes which have been added to the table by Amendment 12.
[11] Paragraph 6.4.4.2, Table 6.4-1, Column 5, Precision Category II or III
This amendment adds the superscripted letters ‘e’ and ‘f’ to the distance values mentioned in the column ‘Category II or III’. These letters are a cross‑reference link to footnotes which have been added to the table by Amendment 12.
[12] Paragraph 6.4.4.2, Table 6.4-1, after footnote d
This amendment adds 2 footnotes: the first (identified by an ‘e’) being the standards omitted by Amendment 11; and the second (identified by an ‘f’) stating the cross-referenced distances in Table 6.4-1 may need to be increased to avoid interference with radio navigation aids.
[13] After paragraph 7.1.3.3
Subsection 7.1.3 relates to control of obstacles of various forms around an aerodrome. This amendment inserts a note advising readers of the subsection to also consider the information in subsection 11.1.4A regarding siting of equipment and installations on taxiway strips.
[14] After subsection 7.2.3
This amendment adds a requirement for operators of aerodromes to make available a Precision Approach Terrain Chart – ICAO for each precision approach runway Category II or III runway. A Precision Approach Terrain Chart – ICAO provides detailed terrain profile information within a defined portion of the final approach to assist aircraft operators with operational planning. Provision of this type of chart is an ICAO standard.
[15] Subsections 8.3.7 and 8.3.7A
This amendment replaces the existing standards for a fixed distance marking and Australia-unique touchdown zone markings (a type of painted marking on the runway surface used to enhance pilot situation awareness) with standards for an ICAO Annex 14-compliant aiming point and touchdown zone markings. The new markings will become mandatory for precision runways after 30 May 2013 for aerodromes that service international flights and 29 May 2014 for other aerodromes with precision runways. Equivalent standards to the original fixed distance marking and Australia-unique touchdown zone markings apply for non-precision or non-instrument runways, however, aerodrome operators may voluntarily implement the new Annex 14‑compliant markings on these runways.
[16] Subparagraph 9.1.1.1 (d)
Paragraph 9.1.1.1 currently has a provision that exempts existing aerodrome lighting facilities from compliance with MOS Part 139 lighting standards until specified events occur. These events include:
(a) the light fittings of a lighting system being replaced with fittings of a different type; and
(b) the facility being upgraded; and
(c) there being a change in the category of either:
(i) aerodrome layout; or
(ii) aerodrome traffic density; and
(d) in exceptional circumstances, CASA determining that in the interest of safety, a lighting facility had to meet the standards of the MOS.
This amendment adds an additional trigger event of an aerodrome supporting operations where the visibility is less than 550 m or the cloud ceiling is below 200 ft above ground level. Compliance following this trigger event becomes mandatory on 29 May 2014. Until then, aerodrome operators may voluntarily elect to comply.
[17] Paragraph 9.1.11.1, the Note
Subsection 9.1.11 provides standards for the weight and frangibility of light fixtures and supporting structures. This amendment inserts a note advising readers of the subsection to also consider the information in subsection 11.1.4A regarding siting of equipment and installations on operational areas.
[18] After paragraph 9.1.14.9A
Paragraphs 9.1.14.9 and 9.1.14.9A provide standards for monitoring of lighting systems used to control aircraft movement. This amendment inserts a note recommending, for runways meant for use in visibility conditions of less than 550 m, that aerodrome operators provide a suitable monitoring system for lighting systems, in addition to those used to be used to control aircraft movement.
[19] Subsection 9.7.2
This amendment adds the standards for an additional type of approach lighting system that may be used for a precision approach Category I runway. The standards for the original type of approach lighting system are retained and aerodrome operators have the option to use either system.
[20] Subsection 9.7.3
This amendment adds the standards for an additional type of approach lighting system that may be used for a precision approach Category II or III runway. The standards for the original type of approach lighting system are retained and aerodrome operators have the option to use either system.
[21] Subparagraph 9.10.18.1 (a)
This amendment changes the standard for the number of runway end lights from a total of 6 lights to ‘at least 6 lights’. This amendment is complimentary to Amendment 22 which requires runway end lights for a precision approach runway Category III spaced at intervals not exceeding 6 m. With at least 1 precision approach runway Category III having a width of 60 m, the new standard allows the full complement of required runway end lights to be provided.
[22] Subparagraph 9.10.18.1 (a)
This amendment inserts a new standard to the effect that a precision approach runway Category III must have runway end lights with a spacing not exceeding 6 m. This is an ICAO Annex 14 standard.
[23] After paragraph 9.10.25.1
This amendment inserts a note to remind readers that if a precision approach Category II or Category III lighting system is provided, it is necessary to also provide touchdown zone lights. This note replaces the original ‘standard’ at paragraph 9.10.25.2 (omitted by Amendment 24).
[24] Paragraph 9.10.25.2
This amendment omits a statement in the MOS which stated it is implicit that touchdown zone lights must be provided where Categories II and III approach lights are provided. The statement was effectively advice and was better stated as a note. This change was done at Amendment 23.
[25] Subparagraph 9.13.11.2 (a)
This amendment changes the existing standard for when alternating green and yellow taxiway centreline lighting must be used so as to include the portion of taxiway from the runway centreline to the perimeter of an instrument landing system sensitive area.
[26] After subsection 9.19.3
For runways used when the visibility is less than 350 m, this amendment inserts a requirement for aerodrome operators to provide a suitable road holding position light at each road-holding position serving a runway.
[27] Subparagraph 9.20.2.5 (d) and the Note
This amendment inserts a new standard for the minimum acceptable levels of serviceability for individual lights or lighting systems used for a precision approach runway Category II or III, a runway meant for take-off in visibility conditions of less than 550 m and a taxiway intended for use in RVR conditions of less 350 m.
[28] After subsection 11.1.4
This amendment inserts a set of new standards relating to safeguarding runway environments and navigation equipment installations. The standards detail minimum distances that people, vehicles, aircraft and non-essential equipment must be kept from runways and navigation equipment installations. The changes adopt ICAO Annex 14 SARPs in this regard.
[29] Subsection 11.1.8
This amendment substitutes revised general information on the components that make up an instrument landing system (ILS).
[30] Subsection 11.1.9
This amendment substitutes revised requirements for an aerodrome operator to consult with the relevant aeronautical telecommunications service and radio navigation service provider to establish adequate arrangements for protecting the ILS installations from interference by a vehicles, plant and aircraft.
[31] Subsection 11.1.10
This amendment substitutes revised requirements for establishing ILS critical and sensitive areas. These critical and sensitive areas are areas derived by computer modelling from which vehicles, plant and aircraft must be excluded to prevent interference with the navigation signals produced by an ILS.
[32] Subsection 11.1.11
This amendment substitutes revised requirements for protecting marker beacons from interference by buildings, power and telephone lines and vegetation.
Schedule 2 Amendments
[1] Paragraph 5.1.2.5
This amendment changes the scope and detail of the various types of aerodrome lighting and lighting infrastructure which must be provided by an aerodrome operator for publication in the AIP.
[2] After paragraph 5.1.2.10
This amendment adds a requirement for aerodrome operators to provide details of the procedures used at the aerodrome in conditions of low cloud or reduced visibility (low visibility procedures) for publication in the AIP.
[3] Section 10.17
This amendment inserts a revised subsection on the standards for conduct of operations during conditions of reduced cloud ceiling or low visibility. The standards cover the factors to be addressed in developing the procedures, the circumstances for applying the procedures and a requirement for periodic review of the procedures to ensure they are fit for the purpose.
[4] After section 10.18
This amendment inserts a set of new standards relating to the training, appointment and duties of persons conducting RV assessments, and the facilities and procedures for conducting RV assessments. An RV assessment is an assessment of the visibility along a particular runway taken from specific points. Information about the visibility along a runway is important for aircraft operations, particularly in marginal weather conditions.