Explanatory Statement
Civil Aviation Regulations 1988
Determination of meteorological minima
Purpose
This determination revokes and replaces instrument CASA 237/10, thereby implementing new take-off and landing minima for aeroplanes and helicopters operating at aerodromes.
Legislation
Subsection 98 (1) of the Civil Aviation Act 1988 (the Act) provides that the Governor‑General may make regulations for the Act and in the interests of the safety of air navigation.
The Civil Aviation Regulations 1988 (CAR 1988) are made under subsection 98 (1) of the Act. Subregulation 257 (1) of CAR 1988 empowers the determination of meteorological minima for the landing or taking off of aircraft.
Related instruments
The determination of meteorological minima is 1 of a package of 4 inter-related instruments dealing with low visibility operations arising from the same background, the other 3 being a MOS Part 139 amendment, 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 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 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 – I.F.R. 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 assessment, in addition to an 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 the new determination on take-off and landing minima that revokes and replaces instrument CASA 237/10.
Key features of specific changes to take off and landing minima
A Take-off minima for aeroplanes
In addition to the existing requirements, the following 2 new requirements are introduced for a take-off at an aerodrome without an air traffic control service when the visibility is less than 800 m:
- the take-off may be conducted only by day
- the aerodrome must be one at which carriage of radio is mandatory.
Impact
The changes are safety enhancements intended to reduce the possibility of collision with objects including vehicles, other aircraft and animals that may be obscured by the combination of darkness and foggy conditions. Given that the safety practices of many operators would preclude take-offs under these conditions, CASA’s assessment is that the new requirements will have a low impact on aircraft operations.
B Take-off minima for multi-engine aeroplanes if engine failure requires return to departure aerodrome for landing
A new requirement is included to the effect that if the performance of a multi-engine aeroplane is such that a return to land at the departure aerodrome will be necessary in the event of an engine failure, then the meteorological conditions at the departure aerodrome must be:
- above limits for an instrument approach at the aerodrome; or
- such as to allow the pilot to return for landing by making a visual approach.
Impact
There is no anticipated impact for aircraft operators because the new standard formalises existing expectations and practice.
C Take-off minima for helicopters
The new instrument rewords the schedule covering take-off minima for helicopters for greater clarity, but without changing the existing minima.
Impact
There is no anticipated impact for helicopter operators because the minima and associated requirements are unchanged.
D Specification of existing operational requirements
The new instrument specifies a number of operational requirements associated with the take-off minima. Although these operational standards have been in effect for many years, they were not formally enacted by legislative instrument. The new instrument achieves this.
Impact
There is no anticipated impact for aeroplane or helicopter operators because the minima and associated requirements are unchanged.
Specific details of the determination are set out in Appendix 1.
Legislative Instruments Act
The determination is a legislative instrument and is subject to registration, and tabling and disallowance in the Parliament, under sections 24, 38 and 42 of the Legislative Instruments Act 2003 (the LIA).
Consultation
Consultation under section 17 of the LIA has taken place under the NPRM process described above.
As noted, NPRM 0906AS – I.F.R. 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 (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 determination commences on 2 June 2011. Implementation is delayed to allow the procedural changes to be incorporated in the Aeronautical Information Publication (AIP) at the next internationally recognised amendment date, and to give aerodrome operators some lead time to implement the necessary changes.
The instrument has been made by the Director of Aviation Safety, on behalf of CASA, in accordance with subsection 73 (2) of the Act.
[Instrument number CASA 70/11]
Appendix 1
Determination of meteorological minima
1 Commencement
Under this section, the instrument commences on 2 June 2011.
2 Revocation
Under this section, the previous determination, instrument CASA 237/10, is revoked.
3 Determination
(1)Under this subsection, the meteorological minima for an I.F.R. aeroplane taking off are as determined in Part A or Part B of Schedule 1, subject to any conditions mentioned in the Part.
(2)Under this subsection, the meteorological minima for an I.F.R. helicopter taking off are as determined in Part C or Part D of Schedule 1, subject to any conditions mentioned in the Part.
(3)Under this subsection, the meteorological minima for an I.F.R. aircraft landing are as determined in Schedule 2.
A Note explains that under regulation 257 of CAR 1988, unless exempted by CASA under regulation 308, it is a strict liability offence if an aircraft takes off or lands below any of the minima determined for the aircraft.
4 Definitions
Under this section, various acronyms, words and phrases in the instrument are defined. Thus:
AIP means Aeronautical Information Publication.
CAO means Civil Aviation Order.
defined point after take-off means the point within the take-off and initial climb phase before which the helicopter’s ability to continue the flight safely, with 1 engine inoperative, is not assured and a forced landing may be required.
LSALT means lowest safe altitude.
MSA means minimum sector altitude.
MTOW means maximum take-off weight.
PC1 means performance class 1 and is the class of helicopter performance such that in the event of failure of the critical power-unit the helicopter is able either to land within the rejected take-off distance available, or to safely continue the flight to an appropriate landing area, depending on when the failure occurs.
PC2 means performance class 2 and is the class of helicopter performance such that in the event of critical power-unit failure performance is available to enable the helicopter to safely continue the flight except when the failure occurs early during the take-off manoeuvre or late in the landing manoeuvre, in which cases a forced landing may be required.
qualifying multi-engine aeroplane means an I.F.R. aeroplane to which Part A of Schedule 1 applies.
qualifying multi-engine helicopter means an I.F.R. helicopter to which Part C of Schedule 2 applies.
RVR means runway visual range and is measured by instrument and reported by Air Traffic Control (ATC).
TODA means take-off distance available.
Schedule 1 Take-off minima for aircraft
Schedule 1 is comprised of 4 Parts. Parts A and B deal respectively with certain multi-engine I.F.R. aeroplanes and other I.F.R. aeroplanes, including conditions on the use of minima.
Parts C and D deal respectively with certain multi-engine I.F.R. helicopters, and other I.F.R. helicopters, including conditions on the use of minima.
Part A Take-off minima for certain multi-engine I.F.R. aeroplanes
1 Under this clause, Part A is expressed to apply to a multi-engine I.F.R. aeroplane (known as a qualifying multi-engine aeroplane) that meets each of the following requirements:
(a) the aeroplane is:
(i) 2 pilot operated; or
(ii) a single pilot operated jet aeroplane; or
(iii) a single pilot operated propeller aeroplane with operative auto feather; and
(b) for an aeroplane with a MTOW exceeding 5 700 kg — the aeroplane is able to meet the relevant obstacle clearance requirements of CAO 20.7.1B; and
(c) for an aeroplane with a MTOW not exceeding 5 700 kg:
(i) the gross climb gradient performance is at least 1.9% under ambient conditions with the loss of the most critical engine; and
(ii) the aeroplane engine-out climb gradient under ambient conditions specified in the manufacturer’s data is at least 0.3% greater than the obstacle free gradient for the runway length required; and
(iii) the pilot in command uses published obstacle free gradients only if such gradients are surveyed to at least a distance of 7 500 m from end of TODA; and
(An interposed Note explains that all runways with strip widths of 150 m or greater are surveyed to 7 500 m unless otherwise annotated in the AIP.)
(iv) an operator-established obstacle free gradient is used only if:
(A) the gradient (having a 150 m baseline at the end of TODA), 12.5% splays, and 7 500 m distance) is established not more than 30° from runway heading; and
(B) the procedures involve not more than 15° of bank to track within the splay; and
(d) for a 2-pilot operation — each pilot is:
(i) endorsed on type; and
(ii) multi-crew trained on type; and
(iii) multi-crew proficiency checked within the previous 13 months; and
(iv) instrument rated.
2 Under this clause, where all of the relevant, applicable qualifying criteria are met, the take-off minima for a qualifying multi-engine aeroplane are:
(a) a ceiling of zero feet; and
(b) visibility of:
(i) 550 m —but only if the following conditions are complied with:
(A) the runway must have illuminated edge lighting at spacing intervals not exceeding 60 m, and centreline lighting or centreline markings; and
(B) if the aerodrome is a non-controlled aerodrome, or a controlled aerodrome without ATC in operation — the take-off must be conducted by day only, and the aerodrome must be one at which carriage of radio is mandatory; or
(ii) 800 m.
3Under this clause, it is a condition of the use of the take-off minima by a qualifying multi-engine aeroplane under Part A that the pilot in command of the aeroplane must ensure that:
(a) if a return to land at the departure aerodrome will be necessary in the event of an engine failure — the meteorological conditions must be at or above instrument approach and landing minima for the aerodrome or such as to allow a visual approach; and
(b) if engine failure occurs at any time after V1, lift-off, or encountering non‑visual conditions — terrain clearance is assured until reaching either en route LSALT or departure aerodrome MSA; and
(c) if a return to the departure aerodrome is not possible — the aeroplane’s performance and fuel availability must each be adequate to enable the aeroplane to proceed to a suitable aerodrome, having regard to terrain, obstacles and route distance limitations.
Part B Take-off minima for other I.F.R. aeroplanes
1 Under this clause, Part B is expressed to apply to an I.F.R. aeroplane that is NOT a qualifying multi-engine aeroplane within the meaning of Part A.
2 Under this clause, the take-off minima for the aeroplane are:
(a) a ceiling of 300 ft; and
(b) visibility of 2 000 m.
3Under this clause, it is a condition of the use of the minima in Part B that the pilot in command of the aeroplane must ensure that:
(a) terrain clearance is assured until reaching either en route LSALT or departure aerodrome MSA; and
(b) if a return to the departure aerodrome is not possible — the aeroplane’s performance and fuel availability are each adequate to enable the aeroplane to proceed to a suitable aerodrome, having regard to terrain, obstacles and route distance limitations.
4Under this clause, it is a condition of the use of the minima in Part B that
(a) if a return to land at the departure aerodrome will be necessary in the event of an engine failure — the meteorological conditions must be at, or above, instrument approach and landing minima for the aerodrome or such as to allow a visual approach; and
(b) that for any multi-engine aeroplane if engine failure occurs at any time after V1, lift-off, or encountering non-visual conditions terrain clearance must be assured until reaching either en route LSALT or departure aerodrome MSA.
Part C Take-off minima for certain multi-engine I.F.R. helicopters
1Under this clause, Part C applies to a multi-engine I.F.R. helicopter (known as a qualifying multi-engine helicopter) operating in PC1 or PC2.
2Under this clause, the minima for a qualifying multi-engine helicopter are:
(a) clear of cloud:
(i) for helicopters operating in PC1 – until attaining the greater of Vyse or Vmin IMC; or
(ii) for helicopters operating in PC2 – until attaining the greater of Vyse or Vmin IMC, and passing the defined point after take-off; and
(b) visibility of:
(i) 800 m; or
(ii) 550 m, but only if the relevant runway or helicopter landing site has:
(A) illuminated edge lighting at spacing intervals not exceeding 60 m; and
(B) centreline lighting or centreline markings.
3Under this clause, it is a condition of the use of the minima in Part C that after entering instrument meteorological conditions the take-off must be conducted:
(a) either:
(i) in accordance with published I.F.R. departure procedures; or
(ii) if there are no published procedures — such that terrain clearance is assured; and
(b) in a 1-engine inoperative configuration until reaching en route LSALT or departure aerodrome MSA and safe flight can be made to a suitable destination or alternate, or a return to land can be made.
4.Under this clause, it is a condition of the use of the minima in Part C that if a return to land at the departure aerodrome will be necessary in the event of an engine failure, the meteorological conditions must be at or above instrument approach and landing minima for the aerodrome for the instrument approach with the highest visibility and ceiling requirement or such as to allow a visual approach.
Part D Take-off minima for other I.F.R. helicopters
1 Under this clause, Part D applies to an I.F.R. helicopter that is NOT a qualifying multi-engine helicopter within the meaning of Part C.
2 Under this clause, the minima for the helicopter are:
(a) a ceiling of 500 ft; and
(b) visibility of 800 m.
3Under this clause, it is a condition of the use of the minima in Part D that after entering instrument meteorological conditions the take-off must be conducted either:
(a) in accordance with published I.F.R. departure procedures; or
(b) if there are no published procedures — such that terrain clearance is assured;
until reaching either en route LSALT or departure aerodrome MSA and safe flight to a suitable destination or alternate, or a return to land can be made.
4.Under this clause, it is a condition of the use of the minima in Part D that if a return to land at the departure aerodrome will be necessary in the event of an engine failure, the meteorological conditions must be at, or above, instrument approach and landing minima for the aerodrome for the instrument approach with the highest visibility and ceiling requirement or such as to allow a visual approach.
Schedule 2 Landing minima for I.F.R. aircraft
Schedule 2 deals with the landing minima for I.F.R. aircraft.
Under this clause, the landing minima for an I.F.R. aircraft are:
(a) for an aerodrome with an approved instrument approach procedure — the minima specified in the instrument approach chart for carrying out that procedure, being:
(i) a height above runway threshold of not less than 200 ft and visibility of not less than 800 m; or
(ii) a height above runway threshold of not less than 200 ft and an RVR of not less than 550 m in the runway touchdown zone; or
(b) for other aerodromes:
(i) in the case of day I.F.R. – visual approach requirements; and
(ii) in the case of night I.F.R. – VMC from the lowest safe altitude within 3 nautical miles.