AC 90-96 - APPROVAL OF U.S. OPERATORS AND AIRCRAFT TO OPERATE UNDER INSTRUMENT FLIGHT RULES (IFR) IN EUROPEAN AIRSPACE DESIGNATED FOR BASIC AREA NAVIGATION (BRNAV/RNP-5)

Approval of Egyptian operators and aircraft to operate under instrument flight rules (IFR) in European airspace designated for basic area navigation (BRNAV/RNP 5)

EAC91-8.1 Purpose

This circular provides the Egyptian requirements regarding on-board Area Navigation (RNAV) equipment for operators of Egyptian registered or operated civil aircraft, operating in a basic area navigation (BRNAV) environment in the European region. This circular identifies types of RNAV equipment that has been determined to be acceptable for BRNAV.

EAC91-8.3 Related ECAR sections

-ECAR 91.205, 91.703 and 91.704.

-ECAR 121.345,121.355 and appendix G.

EAC91-8.5 Definitions

(a) Area Navigation (RNAV). This is a method, which permits aircraft navigation along any desired flight path within the coverage of the associated navigation aids or within the limits of the capability of self-contained aids, or a combination of these methods. For the purpose of this circular, RNAV equipment is considered to be that equipment which operates by automatically determining aircraft position from one, or a combination, of the following sensors with the means to establish and follow a desired path:

(1) VOR/DME.

(2) DME/DME.

(3) INS* or IRS*.

(4) GPS*.

Note: Equipment marked with an asterisk (*) is subject to the limitations contained in paragraph 91-8.7(d).

(b) Class-1 navigation. Class-1 navigation is any en route flight operation or portion of a flight operation conducted in an area entirely within the officially designated operational service volumes of ICAO standard airways navigation facilities.

(c) Basic RNAV (BRNAV). For the purposes of this circular, BRNAV is defined as RNAV that meets a track keeping accuracy equal to or better than +/- 5 NM for 95% of the flight time (RNP-5). This value includes signal source error, airborne receiver error, display system error, and flight technical error.

(d) Pseudorange. The distance from the user to a satellite plus an unknown user clock offset distance. With four satellite signals it is possible to compute position and offset distance. If the user clock offset is known, three satellite signals would suffice to compute a position.

(e) Receiver Autonomous Integrity Monitoring (RAIM). A technique whereby a GPS receiver/processor monitors the GPS. This integrity determination is achieved by a consistency check among redundant measurements.

(f) Required Navigation Performance (RNP). This is a statement of the navigation performance necessary for operation within a defined airspace.

(g) Required Navigation Performance Type (RNP Type). RNP types are established according to navigational performance accuracy in the horizontal plane, that is, lateral and longitudinal position fixing. The type is identified as an accuracy value expressed in nautical miles (e.g., RNP-5).

EAC91-8.7 Related reading materials.

(a) ICAO Doc.7030/4 Regional Supplementary Procedures.

(b) ICAO Doc.9613-AN/937 Manual on Required Navigation Performance (RNP) types.

(c) JAA LEAFLET No. 2 rev. 1: AMJ 20X2 - Guidance Material on Airworthiness Approval and operational criteria for the use of navigation systems in European air space designated for Basic RNAV operations.

(d) FAA AC 90-96 approval of operators & aircraft to operate under IFR in European Airspace Designated for Basic Navigation (BRNAV/RNP-5).

(e) FAA AC 20-130A, Airworthiness Approval of Navigation or Flight Management Systems Integrating Multiple Navigation Sensors.

(f) FAA AC 20-138 (current edition), Airworthiness Approval of Global Positioning System (GPS) Navigation Equipment for Use as a VFR and IFR Supplemental Navigation System.

(g) FAA AC 25-15 (current edition), Approval of Flight Management Systems in Transport Category Airplanes.

(h) RTCA DO 178B/EUROCAE 12B, Software Consideration in Airborne Systems and Equipment Certification.

EAC91-8.9 Background

(a) Implementation of RNAV is one of the key elements to obtain system capacity improvements and should allow airspace users to benefit from more direct routings and greater fuel savings. In European airspace, RNAV will allow greater flexibility in airspace design and reduce the need to depend totally on ground-based point source navigation aids when planning Air Traffic Services (ATS) routes.

(b) RNP-5 was chosen for the initial stage of RNAV operations in European airspace to take account of existing aircraft equipage and the current navigation infrastructure. Only RNAV equipped aircraft having a navigation accuracy meeting RNP-5 may plan for operations under IFR on the ATS routes of the Flight Information Regions (FIR)/Upper Information Regions (UIR) and/or designated Standard Instrument Departures (SID) and Standard Terminal Arrival Routes (STAR) in/out of Terminal Management Areas identified in ICAO Regional Supplementary Procedures Doc 7030/4, paragraph 14.2.1. The RNP-5 value includes signal source error, airborne receiver error, display system error, and flight technical error.

(c) Joint Aviation Authorities (JAA) first published advisory material for the Airworthiness Approval of Navigation Systems for use in designated European airspace for BRNAV operations in July 1996. This material was developed by EUROCAE WG-13 and was commonly referenced as AMJ 20X2. In May 1997, revision 1 to AMJ 20X2 was expanded to include specific guidance on the approval and use of GPS-based equipment for the purposes of conducting BRNAV operations.

(d) This Circular identifies eligible navigation system types and the criteria that should be used to determine acceptable means of compliance for Egyptian operators conducting Class I navigation in European BRNAV airspace. ECAA approval of Egyptian operators for European BRNAV operations is based on consideration of existing systems and previously completed airworthiness approvals, as described in the Airplane Flight Manual (AFM), or an assessment process described in this AC.

EAC91-8.11 Approval process for BRNAV

(a) Operators should submit an application to the FSSS in the form and manner and contain information prescribed by the ECAA. Each operator must submit his application at least 30 days before the date of intended operation along with the following:

(1) Eligibility Airworthiness Documents. Sufficient documentation should be available to establish that the aircraft has an appropriate AFM, AFM Supplement (AFMS), if applicable. and is otherwise suitably qualified to fly the intended routes .

(2) Description of Aircraft Equipment to be used for RNP-5 operations.

(3) RNP-5 Time Limit for Inertial Navigation Systems (INS) or Inertial Reference Units (IRU) (if applicable).

(4) Operational Training Programs and Operating Practices and Procedures.

(5) Operational Manuals and Checklists.

(6)Operating history that identifies relevant past problems and incidents, if any, and actions taken to correct the situation.

(7) Minimum Equipment List (MEL) relevant updates.

(8) Maintenance program relevant updates.

(9) Awareness of the necessity to follow up action after navigation error reports, and the potential for removal of RNP-5 operating authority.

(b) Operators should address the guidance contained on RNAV system equipage, eligibility and usage limitations; the general operating procedures specified in the pilot knowledge items the flight plan procedures, and any policy or procedures related to BRNAV operations that are required by European Civil Aviation Authorities. (ECAR 91, section 91.703, paragraph (a)(2) requires that the operator "when within a foreign country, comply with the regulations relating to the flight and maneuver of aircraft there in force"). discusses the documents and the processes that should be used for approval of operators and RNAV systems.

EAC91-8.11 Operator/RNAV system approval for BRNAV in designated European BRNAV airspace.

(a) Aircraft equipage. An aircraft may be considered eligible for BRNAV approval if it is equipped with one or more RNAV systems approved and installed in accordance with the guidance contained in this document. The minimum level of availability and integrity required for BRNAV systems for use in designated European airspace can be met by a single installed system comprising one or more sensors, RNAV computer, control display unit, and navigation display(s) (e.g., HSI, or CDI), provided that the system is monitored by the crew and that in the event of a system failure, the aircraft retains the capability to navigate relative to ground based navigation aids (e.g., VOR, DME, and NDB). Aircraft not suitably equipped will not be permitted to operate in the designated BRNAV airspace.

(b) Operator/RNAV system eligibility based on the Airplane Flight Manual (AFM) (Supplement).

(1) Aircraft BRNAV system eligibility. The aircraft should be considered eligible for BRNAV operations, if the AFM shows that the navigation system installation has received airworthiness approval in accordance with one of the following FAA AC's: AC 20-130A, AC 20-138, AC 25-15 or equivalent. The guidance for airworthiness approval contained in these AC's provides aircraft navigation performance that is equivalent to RNP-5 or better. (See paragraph 7d for limitations on design and use of RNAV systems in European BRNAV airspace). Once equipment eligibility is established, operator approval should proceed in accordance with paragraph (b) (2) or (3), as appropriate.

(2) ECAR 91 Aircraft/Operator approval. Egyptian ECAR 91 operators should review their AFM to establish that it shows RNAV system eligibility as detailed in paragraph (b) (1) of this section. Once RNAV system eligibility has been established, the operator should take steps to ensure that BRNAV operations are conducted in accordance with the guidance contained in this AC as well as any other operational or airspace requirements that may be established by European authorities. When the operator has completed these actions, it may begin to conduct BRNAV operations. See paragraph (c) for actions to take if the operator is not able to determine from the AFM that the aircraft RNAV system has been approved and installed in accordance with an appropriate AC’s as detailed in paragraph (b) (1) of this section.

(3) ECAR 121 air carrier/air taxi operator approval. ECAR Part 121 operators should present the following documentation to the ECAA: Sections of the AFM that document airworthiness approval in accordance with an appropriate standard as detailed in paragraph (b) (1) of this section and training and operations manuals that reflect the operating policies of this AC as well as any other operational or airspace requirements that may be established by ECAA. Once the operator has addressed the guidance in these paragraphs to the satisfaction of the ECAA, the ECAA will update the Operations Specifications to reflect RNP-5 approval. See paragraph (c) of this section for guidance on actions to take if the operator is unable to determine from the AFM whether the aircraft RNAV system has been approved in accordance with an appropriate standard as detailed in paragraph (b) (1) of this section.

(1) The operator may not be able to determine the airborne equipment's eligibility from the AFM, or may require a BRNAV time limit extension for non-radio updated INS-based RNAV systems beyond 2 hours. See paragraph (d) (1) of this section. In this case, the operator should provide the FSSS with the RNAV system make, model and part number, evidence from the manufacturer of meeting RNP-5 accuracy and the BRNAV requirements pertaining to, crew operating procedures, bulletins, and any other pertinent information.

(2) For ECAR 91 operations, after the ECAA determines that the navigation equipment is eligible for BRNAV/RNP-5 operations based on the documentation provided by the operator, the FSSS will issue a letter documenting that finding to the operator. For ECAR Part 121 operators, the FSSS will establish aircraft RNAV system eligibility and determine that the operator's training and operations manuals reflect the operating policies of this AC. Once these steps are completed, the Operations Specifications (B36) for ECAR Part 121 operators may be revised to reflect RNP-5 approval.

(d) Limitations on the design and/or use of navigation systems. Although the following navigation systems have RNAV capability, limitations are required for their use when conducting operations in designated BRNAV airspace.

(1) Inertial Navigation Systems (INS). Those approved INS system installations which meet the required functions, but do not have automatic radio navigation updating of INS position, are limited to a maximum 2-hour time limit for operation in designated BRNAV airspace from the time that the system is placed in the navigation mode (NAV SELECT). The ECAA will give consideration to extending the 2-hour time limit for specific INS configurations. The ECAA will coordinate this effort with the JAA. Requests for time extensions should be submitted with supporting rationale and data to ECAA, for evaluation.

Note: Certain INSs perform automatic radio navigation aid updating after the pilot makes a manual selection of navigation aids. Such systems are not limited to the 2-hour time limit provided that the operator has established procedures for pilots to follow.

(2) GPS.

(i) GPS design. GPS installed in accordance with FAA AC 20-138 or equivalent should provide pseudorange step detection and health word checking functions in accordance with TSO-C129a, or equivalent. Compliance with these requirements can be established by one of the following:

(A) A statement in the AFM(s) that the GPS equipment meets the criteria for primary means of navigation in oceanic and remote airspace, or

(B) A placard on the GPS receiver evidencing it meets TSO-129a or equivalent, or

(C) A letter of design approval for the applicable equipment. Operators should contact the avionics installer or manufacturer to determine if the equipment complies and if a letter of design approval is available. Operators should keep this letter with the AFM entry as evidence of BRNAV eligibility. Any limitations included in the letter of design approval should be reflected in a letter of finding to ECAR Part 91 operators, or

(D) GPS equipment that has been approved in accordance with TSO C-129 or equivalent, but which does not satisfy the step detection and health word checking, may still obtain a letter of design approval for BRNAV. In this case, BRNAV operations are limited to flights where Receiver Autonomous Integrity Monitoring (RAIM) outages do not exceed 5 minutes. With this restriction, TSO C-129 or equivalent equipment is similar to equipment that provides step detection and health word checking. The maximum RAIM outage should not be extended beyond 5 minutes for TSO C-129 or equivalent.

(b) Flight planning restrictions for GPS. During pre-flight planning, if 24 satellites (23 if baro aiding is incorporated into the GPS installation) are projected to be operational for the flight, then the aircraft can depart without further action. If, however, 23 or fewer satellites (22 if baro aiding incorporated), are projected to be operational, then the availability of GPS integrity (RAIM) should be confirmed for the intended flight (route and time). This should be obtained from a prediction program that is provided in the GPS unit installed in the aircraft, a prediction program run outside the aircraft (such a program should use the same algorithms as those in the aircraft GPS units), or from an alternative method considered acceptable to the ECAA after review of JAA comments on the method proposed. (Appendix 1 contains basic criteria for RAIM Prediction Programs). In the event of a predicted continuous loss of RAIM of more than 5 minutes for any part of the intended flight, the flight should be delayed, canceled, or rerouted on a track where RAIM requirements can be met. Alternate methods should be submitted for approval through FSSS.

(c) Loss of RAIM en route. In the event of loss of the RAIM detection function, the GPS stand-alone equipment may continue to be used for navigation as long as the cockpit crew determines, by cross checking other on-board navigation systems that the GPS system is continuing to provide an acceptable level of IFR navigation performance. Otherwise, the crew should notify ATC and revert to an alternative means of navigation (e.g., VOR, DME, or NDB).

(d) Actions when failure is detected. In the event of a detected failure (including detected failure of satellites for GPS-based RNAV systems), the crew should notify ATC and revert to an alternative means of navigation.

(e) Availability of VOR, DME, OR ADF. VOR, DME or ADF capability should be installed and operative consistent with the applicable operating rules (e.g., ECAR 91 and 121) and intended route-of-flight to ensure availability of a suitable alternative means of navigation in the event of GPS/RNAV system failure.

EAC91-8.13 BRNAV operating procedures (general)

For BRNAV operations, the crew should be familiar with the normal operating procedures and the contingency procedures detailed in this AC.

(a) Normal procedures. The procedures for the use of navigational equipment on BRNAV routes should include the following:

(1) When a navigation database is installed, the database validity should be checked before the flight.

(2) Other NAVAIDs (e.g., VOR, DME, and ADF) should be selected so as to allow immediate cross-checking or reversion in the event of loss of RNAV capability.

(b) Contingency procedures. The crew should be familiar with the following general provision: Pilots should notify ATC of conditions (e.g., equipment failures and weather conditions) that may affect the ability of the aircraft to maintain position within the designated BRNAV airspace. In this case, crews should state their intentions, coordinate a plan of action, and obtain a revised ATC clearance. If unable to obtain an ATC clearance prior to deviating from the BRNAV airspace, the crew should follow established contingency procedures, as defined by the region of operation, and obtain an ATC clearance as soon as possible.

EAC91-8.15 Pilot knowledge

Pilots should be knowledgeable in the following areas:

(a) RNP definition as it relates to BRNAV requirements in European airspace;

(b) Airspace where RNP-5 is required;

(d) Navigation equipment required to be operational for flight in designated BRNAV airspace, limitations associated with the RNAV equipment;

(e) Flight planning requirements;

(f) Contingency procedures (e.g., for equipment failure);

(g) En route, terminal, and approach procedures applicable to RNAV; and

(h) The requirements of this circular.

EAC91-8.17 Flight plans

Egyptian operated aircraft filing flight plans into European BRNAV designated airspace are expected to meet the European BRNAV airspace requirements. Operators should indicate approval for BRNAV/RNP-5 operations by annotating block 10 (Equipment) of the ICAO flight plan with the letter "R." If there are any other flight plan annotations required by individual States, operators should make appropriate annotations.

APPENDIX 1

EAC91-8.aa.19 GPS Integrity Monitoring (RAIM) prediction program

Where a GPS Integrity Monitoring (RAIM) prediction program is used as a means of compliance with this AC it should meet the following criteria:

(a) The program should provide prediction of availability of the integrity monitoring (RAIM) function of the GPS equipment, suitable for conducting RNP-5 (BRNAV) operations in designated European airspace.

(b) The prediction program software should be developed in accordance with at least RTCA DO 178B/EUROCAE 12B, level D guidelines.

(c) The program should use either a RAIM algorithm identical to that used in the airborne equipment or an algorithm based on assumptions for RAIM prediction that give a more conservative result.

(d) The program should calculate RAIM availability based on a satellite mask angle of not less than 5 degrees, except where use of a lower mask angle has been demonstrated to be acceptable to the ECAA.

(e) The program should have the capability to manually designate GPS satellites which have been notified as being out-of-service for the intended flight.

(f) The program should allow the user to select:

(1) The intended route and declared alternates;

(2) The time and duration of the intended flight.

APPENDIX 2

EAC91-8.aa.21 Required functions

The following system functions are the minimum required to conduct BRNAV/RNP-5 operations:

(a) Continuous indication of aircraft position relative to track to be displayed to the pilot flying on a navigation display situated in his primary field of view;

Note: In addition, where the aircraft type certificate requires more than one pilot, information to verify aircraft position must be displayed in the non-flying pilot's primary field of view.

(b) Display of distance and bearing to the active (To) waypoint;

(d) Storage of waypoints; minimum of 4; and

(e) Appropriate failure indication of the RNAV system, including the sensors.