Aircraft Certification Policy Letter (ACPL)

ACPL No.: 56
Issue No.:  2
Issue Date:  2002-03-21
AARD File:  5009-0-56

Aircraft Certification Policy Letter (ACPL)

Subject: Reduced Vertical Separation Minima (RVSM) - Airworthiness Approval

1.0 Purpose

The purpose of this ACPL is to provide Headquarters (HQ) and Regional Aircraft Certification personnel, delegates, and industry with background information and guidance for the aircraft certification activities associated with operational approval of Reduced Vertical Separation Minima (RVSM).

2.0 Reference Documents

  1. Transport Canada Airworthiness Notice (AN) D003 - Maintenance Requirements for Aircraft Operating under Reduced Vertical Separation in the North Atlantic Region;
  2. Transport Canada Commercial and Business Aviation Advisory Circular (CBAAC) No. 0186 - Canadian Reduced Vertical Separation Minimum (RVSM) Airspace;
  3. Federal Aviation Administration (FAA) Interim Guidance Material on the Approval of Operators/Aircraft for RVSM Operations, No. 91-RVSM, Change 1 - Approval of Aircraft and Operators for Flight in Airspace Above FL 290 where a 1,000 Foot Vertical Separation Minimum is Applied. Available from the FAA Oceanic Procedures Branch RVSM web site;
  4. Joint Aviation Authorities (JAA) Temporary Guidance Leaflet (TGL) No. 6, revision 1 - Guidance Material on the Approval of Aircraft and Operators for Flight in Airspace above Flight Level 290 where a 300m (1,000 ft) Vertical Separation Minimum is Applied. Available from the EUROCONTROL web site; and
  5. More documentation and information on RVSM can be found at:
    1. The NAV Canada RVSM web site accessible through the Service Projects - RVSM menu item selection at: www.navcanada.ca/navcanada.asp;
    2. The FAA Oceanic Procedures Branch RVSM web site at: http://www.faa.gov/pilots/intl/oceanic_ops/;
    3. The EUROCONTROL (European Organisation for the Safety of Air Navigation) web site for the European RVSM programme at: www.eur-rvsm.com; and
    4. The ARINC Incorporated RVSM web site at: www.arinc.com/rvsm/.

3.0 Background

3.1 There are two aspects of Aircraft Certification activity in the process for approval for RVSM:

  1. The first involves the approval of an aircraft type for RVSM, which is usually handled between the aircraft type certificate or type design holder and Transport Canada HQ; and
  2. The second is associated with the operational approval of a specific aircraft for RVSM operation, which is normally handled through the Regional Aircraft Certification Office.

3.2 The goal of RVSM is to reduce the vertical separation above flight level (FL) 290 from 2,000 ft. minimum to 1,000 ft. minimum. This allows aircraft to fly more optimum profiles, gain fuel savings and increase airspace capacity. The process of safely changing this separation standard required a study to assess the actual performance of airspace users under the current separation (2,000 ft.) and potential performance under the new standard (1,000 ft.). In 1988, the International Civil Aviation Organization (ICAO) Review of General Concept of Separation Panel (RGCSP) completed a study and concluded that safe implementation of the 1,000 ft. separation standard was technically feasible without imposing unreasonably demanding technical or operational requirements. The North Atlantic (NAT) Region was identified as best suited to the first application of the new minimum due to the better-than-average height keeping accuracy shown by the NAT Minimum Navigation Performance Specification (MNPS) approved aircraft and the predominant one-way traffic flow in the NAT Region.

3.3 To implement RVSM and ensure that the required Target Level of Safety (TLS) could be met, a certification process was necessary for those aircraft that would conduct RVSM operations. The FAA and JAA, with ICAO, developed criteria for the airworthiness approval of aircraft to meet the RVSM altitude tolerance criteria.

3.4 Compliance with the altitude tolerance criteria has required aircraft type certificate or type design holders to demonstrate the altitude-keeping performance of their design. This has involved providing a technical justification that the aircraft type can remain within an altitude error tolerance. Many aircraft types required improvements in their autopilot and air data systems, with special attention to the skin waviness in the area surrounding the static ports.

3.5 RVSM airworthiness approval for an aircraft type can occur as part of a group or as a "non group" approval. For an aircraft to be considered a member of a group:

  1. It should have been manufactured to a nominally identical design;
  2. The static system of each aircraft should be installed in a nominally identical manner;
  3. The same static source error correction should be incorporated in all aircraft of the group;
  4. The avionics units installed on each aircraft to meet the minimum RVSM requirements should be manufactured to the same specification and have the same part number; and
  5. The RVSM data package should have been produced or provided by the type certificate or type design holder.

3.6 If the aircraft does not meet these conditions then it must be considered as a non-group aircraft. In most cases, aircraft will have received RVSM airworthiness approval as part of a group.

4.0 RVSM Implementation

4.1 North Atlantic RVSM

As stated in section 3.2, the NAT Region was identified as best suited for first application of the new minimum. Therefore, Phase I of NAT RVSM was implemented from FL 330 to FL 370, inclusive, on March 27, 1997, within MNPS airspace. Phase II of NAT RVSM expanded the MNPS airspace from FL 310 to FL 390, inclusive, on October 8, 1998. Ongoing system performance monitoring and review of aircraft approvals continues during Phase II of NAT RVSM implementation. Phase III of the NAT RVSM will lead to full implementation by expanding the NAT MNPS airspace from FL 290 to FL 410. The Phase III implementation will be concurrent with the implementation of RVSM in Europe.

4.2 West Atlantic Route System RVSM

4.2.1 The West Atlantic Route System (WATRS) Region is a complex, high traffic area that is comprised mostly of fixed routes with a significant number of crossings. There are two dominant traffic flows in the WATRS region. One is between North America and the Caribbean, Bermuda, and South America and the other is between the Americas and Europe. Historically, WATRS traffic has been increasing at an approximate rate of 2.8 percent per year. This trend is expected to continue and consequently, both the FAA and users have agreed that RVSM is needed to accommodate the increased demand for optimum altitudes and routes.

4.2.2 The Phase I plan (implemented September 30, 2000) expanded the FAA designated transition areas to U.S. facilities adjacent to the New York Flight Information Regions (FIR) with the exception of the San Juan Combined Center Radar Approach Control (CERAP). Phase II (implemented November 1, 2001) is defined as the implementation of RVSM for all approved aircraft in the New York FIR portion of WATRS, and the expansion of RVSM transition airspace to include the San Juan CERAP and any remaining portion of Miami Oceanic.

4.3 Asia Pacific RVSM

Australia, Fiji, New Zealand, Tahiti, the United States, Japan, and Papua New Guinea simultaneously implemented RVSM within specified areas of their FIR. Effective 0700 hrs, 24 February 2000 Coordinated Universal Time (UTC), RVSM airspace was prescribed within the Oakland Oceanic FIR and Anchorage Oceanic FIR within controlled airspace between FL 290 and FL 390 inclusive.

4.4 European RVSM Implementation Schedule

EUROCONTROL Provisional Council approved the RVSM Master Plan in April 1999. The following dates serve as the benchmark for the program:

  1. Implementation Date January 2002;
  2. Initial Post Implementation Safety Assessment December 2002; and
  3. Final Post Implementation Safety Assessment December 2004.
4.5 Canadian Northern Domestic Airspace

4.5.1 With the forecast of increased traffic in northern Canadian airspace, including operations on polar routes, the aspects of airspace capacities and operator economies will only become more significant. The increased airspace capacity, while addressing the intercontinental traffic, will also provide opportunities for domestic airspace users in the designated RVSM airspace to operate closer to optimum vertical profiles with the resultant economies.

4.5.2 RVSM will be introduced in Canadian Northern Domestic Airspace April 18, 2002. More information on the implementation of RVSM in Canadian Northern Domestic airspace can be found at the NAV Canada RVSM website, as indicated in section 2.0 of this ACPL.

5.0 Transport Canada Policy

5.1 Airspace where RVSM is applied is considered as minimum navigation performance specification airspace. The appropriate Transport Canada Civil Aviation (TCCA) Branch must approve both the individual operator and the specific aircraft type before an operator may conduct flights in RVSM airspace.

5.2 The specific procedures and technical requirements to be used for airworthiness and operational approvals relating to the introduction of RVSM have been specified in the FAA Interim Guidance Material on the Approval of Operators/Aircraft for RVSM Operations, No. 91-RVSM, Change 1, identified in section 2.0 of this ACPL. Transport Canada has adopted this interim FAA guidance material for RVSM approvals in Canada.

5.3 For foreign aircraft seeking RVSM Operational Approval in Canada, Transport Canada will accept as an alternative to FAA 91-RVSM, JAA Temporary Guidance Leaflet No. 6 Rev 1, titled "Guidance Material on the Approval of Aircraft and Operators for Flight above Flight Level 290 where a 300m (1,000 ft) Vertical Separation Minimum is applied".

6.0 The Approval Process

6.1 General

The specific aircraft type or types that the operator intends to use will need to be approved by Transport Canada before the operator conducts flights in RVSM airspace. Subsequent to the purchase of an aircraft with approved RVSM capability, or incorporation of the provisions prescribed in a Service Bulletin (SB), aircraft owners and operators will need to request the issuance of an airworthiness approval, maintenance procedures and maintenance schedules approval and an operational approval. Subsection 6.2.1 provides guidance for the airworthiness approval of newly built aircraft, aircraft that have already entered service, and non-group aircraft. Subsection 6.2.2 contains guidance on the applicable maintenance requirements for all RVSM operations. Subsection 6.3.1 explains the airworthiness aspects of the operational approval.

6.2 Headquarters Responsibilities

6.2.1 Airworthiness Approval of Aircraft Type

Note:

In the following paragraphs, build standard refers to the aircraft configuration that meets the Minimum Aircraft System Performance Specification of FAA Interim Guidance Material No. 91-RVSM Change 1, or later change as agreed to by Transport Canada.

equipment and systems installations. The approval consists of an RVSM data package that the aircraft type certificate or type design holder submits to the responsible state of design authority. The combination of performance and analytical data, SBs or equivalent, Instructions for Continued Airworthiness (ICA), and the approved amendment or supplement to the Aircraft Flight Manual (AFM) is known as the RVSM approval data package. As a minimum, the RVSM data package should consist of the following items:

  1. A statement of the aircraft group or non-group aircraft and applicable build standard to which the data package applies;
  2. A definition of the applicable flight envelope(s);
  3. Data showing compliance with the RVSM performance and systems criteria;
  4. The procedures to be used to ensure that all aircraft submitted for airworthiness approval comply with RVSM criteria. These procedures will include the references of applicable SBs and the applicable approved AFM amendment or supplement; and
  5. The maintenance instructions that ensure continued airworthiness for RVSM approval.

6.2.1.2 In the case of a newly built aircraft, the aircraft type certificate or type design holder develops and submits to the state of design authority, the performance and analytical data that supports RVSM airworthiness approval of a defined build standard. The data will be supplemented with maintenance and repair manuals giving associated ICAs. Compliance with RVSM criteria will be stated in the AFM including reference to the applicable build standard, related conditions and limitations.

6.2.1.3 In the case of an aircraft already in service, the aircraft type certificate or type design holder submits to the responsible authority, either in the state of design or the state in which the aircraft is registered, the performance and analytical data that supports RVSM airworthiness approval of a defined build standard. The data will be supplemented with a SB, or its equivalent, that identifies the work to be done to achieve the build standard, ICAs, and an amendment to the AFM stating related conditions and limitations.

6.2.1.4 For Canadian aircraft type certificate or type design holders, airworthiness approval is to be obtained from the Aircraft Certification Branch. The aircraft type certificate or type design holder will submit to the Aircraft Certification Branch and the Maintenance and Manufacturing Branch the data package necessary to substantiate compliance with the requirements as stated in FAA Interim Guidance Material No. 91-RVSM Change 1. Upon receipt of Transport Canada approval, the type certificate or type design holder will either incorporate the modification in production aircraft, or issue a SB to aircraft owners and operators applicable to aircraft requiring RVSM approval. These SBs will include appropriate instructions to ensure that each individual aircraft is eligible for inclusion within the defined group.

6.2.1.5 The aircraft type certificate or type design holder will either incorporate a modification in production aircraft, or issue a SB subsequent to approval by the responsible airworthiness authority. Depending on the arrangement that exists between Transport Canada and the responsible airworthiness authority, Transport Canada may become involved in a certification review of the modifications and its associated instructions. The type certificate or type design holder, in accordance with existing arrangements, will initiate this process. Any changes to the SB because of the certification review may result in the type certificate or type design holder issuing a SB specifically for Canadian registered aircraft.

6.2.1.6 The activity required of the Aircraft Certification Branch is different for aircraft that are not part of a group approval. Non-group aircraft will not be discussed in detail in this document other than to say an applicant would have to provide much of the same data that an aircraft type certificate or type design holder would provide for the data package of a group approval. As this would require substantial instrumentation, flight test and analysis, it is usually beyond the scope for an applicant seeking an operational approval of a single non-group aircraft.

6.2.2 Maintenance Approval

The integrity of the design features necessary to make certain that altimetry systems continue to meet RVSM approval criteria should be verified by scheduled tests and inspections in conjunction with an the approval of the maintenance schedule, pre-departure checks and technical dispatch procedures. This approval must be obtained from the appropriate regional Transport Canada Centre.

Note:

Airworthiness Notice (AN) D003 specifies the applicable maintenance requirements.

6.3 Regional Aircraft Certification Responsibilities

6.3.1 Airworthiness Approval of Specific Aircraft as Part of the Operational Approval

6.3.1.1 Operational approval will be required for each aircraft to be used for RVSM operations. Aircraft owners/ operators must apply for this approval through their Principal Operations Inspector (POI) to the Commercial and Business Aviation Branch. Transport Canada will need to be satisfied that:

  1. Each aircraft holds RVSM airworthiness approval. Check with Transport Canada Aircraft Certification Branch in HQ for the status of approval in Canada;
  2. The operator has obtained Transport Canada's approval for the pertinent maintenance procedures and maintenance schedules; and
  3. Where necessary, operating procedures unique to the airspace have been incorporated into the operations manuals.

6.3.1.2 The appropriate Transport Canada Aircraft Certification, Maintenance and Manufacturing, or Commercial and Business Aviation Regional Office can be contacted for additional information on their specific approval requirements.

6.3.1.3 As part of the operational approval process the operator will be required to be height monitored by over flying a ground Height Monitoring Unit (HMU) located at Strumble, U.K. or Gander, NFLD or by the temporary installation of a GPS Monitoring Unit (GMU). ARINC has:

  1. Developed the GMU under contract from the FAA. Portable GMUs are available for monitoring from ARINC. Monitoring may be conducted by ARINC personnel at the operators request or by the operator themselves through a loan agreement with ARINC. The GMU comprises a laptop PC-based computer and data retrieval system with a GPS receiver and antenna. The antenna is to be fastened to an appropriate window inside the aircraft.
  2. Undertaken to obtain Supplemental Type Certificates (STCs) for the temporary installation of the GMU on most aircraft types that will require RVSM approval. If an FAA STC is available at the time GMU monitoring takes place, the GMU will be installed and operated in accordance with the provisions of the STC. Transport Canada Regional Offices will be required to familiarize the STC in the normal manner.

6.3.1.4 In the event that ARINC has not obtained an STC for the installation of a GMU on a particular aircraft type or model, the owner or operator must apply for a Canadian Limited STC (LSTC). In this event, Regional Offices should consult with the Aircraft Certification Branch Engineering (AARDD) and Flight Test (AARDC) Divisions in HQ, for guidance.

7.0 Operational Specification

Approval to operate in RVSM airspace will be granted through the issuance of an Operations Specification. The Operations Specification will be issued through the appropriate Commercial and Business Aviation regional office once the required airworthiness approval and operational approval have been granted and the operator has met the Height Monitoring requirements.

8.0 Termination Date

This ACPL will be rescinded upon the publication of the appropriate Airworthiness Manual Advisory (AMA).

Original signed by:

Maher Khouzam
Chief, Regulatory Standards
Aircraft Certification Branch

 

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