Appendix A A-25 A.8.3.6 The methodology described above for Group approval is statistical in nature.
This is the result of the statistical nature of the risk analysis and previous statistical statements made when developing RVSM. In the context of a statistical method, a statement that, “Each individual aircraft in the Group must be built to have ASE contained within ±200 ft,” does not mean every airframe should be calibrated with a trailing cone or equivalent to demonstrate ASE is within 200 ft. Such an interpretation would be unduly onerous.
However, if any aircraft is identified as having an error exceeding ±200 ft, then it should receive corrective action.
A.8.4 ASE Component Error Budget: Non-Group Approval. Where an aircraft is submitted for approval as a Non-Group aircraft, the data should be sufficient to show the requirements of paragraph A.5.3.2 are met. The data package should specify how the ASE budget has been allocated between residual SSE and avionics error. The operator and the FAA should agree on what data will satisfy approval requirements. The following data should be acquired and presented:
1. Calibration of the avionics used in the flight test as required establishing a ctual avionics errors contributing to ASE. Since the purpose of the flight test is to determine the residual SSE, specially calibrated altimetry equipment may be used.
2. All avionics equipment contributing to ASE must be identified by function and part number. The applicant must demonstrate the avionics equipment can meet the requirements established according to the error budget when operating the equipment in the environmental conditions expected during RVSM operations.
3. Specifications for the installed altimetry avionics equipment indicating the largest allowable errors must be presented. The error sources shown in items 1 through 5 under paragraph A.7.2 are necessary elements of the altimetry system component error budget for a Non-Group aircraft.
A.9 Establishing and Monitoring SSEs.
A .9.1 General. Paragraph A.8.3.4 requires the methodology used to establish the SSE be substantiated. Further, maintenance procedures must be established to ensure conformity of both newly manufactured airplanes and those with in-service history. There may be many ways of satisfying these requirements; two examples are included below.
A.9.1.1 Examp le 1: Group Aircraft. One process for showing compliance with RVSM requirements is shown in Figure A-5, Process for Showing Initial and Continued Compliance of Airframe Static Pressure System. Figure A-5 illustrates flight test calibrations and geometric inspections will be performed on a given number of aircraft. The flight calibrations and inspections will continue until a correlation between the two is established. Geometric tolerances and SSEC will be established to satisfy RVSM requirements. For aircraft being manufactured, every Nth aircraft will be inspected in detail and
Appendix A A-26 every Mth aircraft will be flight test calibrated, where N and M are determined by the manufacturer and agreed to by the approving authority. The data generated by N inspections and M flight calibrations must be used to track the mean and 3 SD values to ensure continued compliance of the model with the requirements of paragraphs A.5.2.1 and A.5.2.2. As additional data are acquired, they should be reviewed to determine if it is appropriate to change the values of N and M as indicated by the quality of the results obtained.
A.9.1.1.1 There are various ways in which the flight test and inspection data might be use d to establish the correlation. The example shown in Figure A-6 is a process in which each of the error sources for several airplanes is evaluated based on bench tests, inspections, and analysis. Correlation between these evaluations and the actual flight test results would be used to substantiate the method. A highly favorable correlation may be used to augment flight test data, and if appropriate, mitigate the need to conduct periodic flight tests (every Mth aircraft) as presented in paragraph A.9.1.1 above.
A.9.1.1.2 Th e method illustrated in Figures A-5 and A-6 is appropriate for new models since it does not rely on any preexisting database for the Group.
A.9.1.2 Exam ple 2: Group Aircraft. Figure A-7, Process for Showing Initial and Continued Compliance of Airframe Static Pressure Systems for In-Service and New Model Aircraft, illustrates flight test calibrations should be performed on a given number of aircraft and consistency rules for air data information between all concerned systems verified. Geometric tolerances and SSEC should be established to satisfy the requirements. A correlation should be established between the design tolerances and the consistency rules. For aircraft being manufactured, air data information for all aircraft should be checked in terms of consistency in cruise conditions and every Mth aircraft should be calibrated, where M is determined by the manufacturer and agreed to by the approving authority. The data generated by the M flight calibrations should be used to track the mean and 3 SD values to ensure continued compliance of the Group with the requirements of paragraphs A.5.2.1 and A.5.2.2.
A.9.1.3 Non-G roup Aircraft. Where airworthiness approval has been based on flight tests, the continuing integrity and accuracy of the altimetry system must be demonstrated by periodic ground and flight tests of the aircraft and its altimetry system at periods to be agreed with the approving authority.
However, exemption from flight test requirements may be granted if the applicant can adequately demonstrate the relationship between any subsequent airframe/system degradation and its effects on altimetry system accuracy is understood and adequately compensated/corrected for.
Appendix A Figure A-5. Process for Showing Initial and Continued Compliance of Airframe Static Pressure System Flight test calibration Geometric inspections of all aircraft Number of aircraft as required flight tested (or more as required) to to meet the objective below meet objective below
OBJECTIVE OF INITIAL CALIBRATIONS AND INSPECTIONS
1. Establish correlation between geometric inspections and flight calibrations.
2. Establish geometric tolerances and SSEC necessary to show compliance with RVSM requirements Inspect each aircraft until confidence of geometric compliance is established Geometric inspection of every Nth aircraft Flight test calibrate every Mth aircraft Figure A-6. Compliance Demonstration Ground-To-Flight Test Correlation Process Example Conduct ADC ground Measure fuselage Fuselage flight test calibration geometric geometric calibration conformance conformance using inspection with xx ? Yes tool No Y Perform an Remove ADC calibration Rework analysis to estimate error airplane position error Ground Checks Combine AOA vane functional/ calibration estimated P/S probe installation/ alignment component Flush static port installation error Estimated A-27
Appendix A Figure A-7. Process for Showing Initial and Continued Compliance of Airframe Static Pressure Systems for In-Service and New Model Aircraft Corresponding Documents and Results Tests * Identification of Static Pressure Error.
With development aircraft Flight Test Calibration (see note 1) * Establish the SSEC Laws for the * Certification Cards. Demonstration Air Data Computers. of compliance with requirements. Airworthiness Assessment * Definition of Consistency Rules.
- - For Each New Aircraft * Use the pre-delivery flight(s) to check the coherence of the air data information * Record data from captain's side Airworthiness Authorities Results Geometrical Inspection and Satisfactory? •NO→ Theoretical Analysis.
Repairs, if necessary.
Aircraft Cruise Calibrate Every TBD Aircraft in Flight Manufacturer Responsibility Note 1: The flight test installation chosen to get the calibration data shall have an accuracy compatible with the level of performance to be demonstrated and an analysis of this accuracy shall be provided. Any possible degradation of this accuracy shall be monitored and corrected during the flight test period.
A-28
Appendix A A-29 A.10 Maintenance Requirements.
A.10.1 G eneral . The data package must include a definition of the procedures, inspections/tests, and limits used to ensure all aircraft approved against the data package “conform to type design.” All future approvals, whether of new build or in-service aircraft, must also meet the error budget allowances developed according to paragraph A.8. The tolerances will be established by the data package and include a methodology allowing for tracking the mean and SD for new build aircraft.
A.10.1.1 D efine compliance requirements and test procedures for each potential source of ASE. Ensure the error sources remain as allocated in the ASE budget.
Provide guidance for corrective action in the event of equipment, test, and/or inspection failure. Typical RVSM-specific maintenance procedures include the following:
1. Verification of avionics component part numbers.
2. ADS Ground Test. This is a direct assessment of altimetry system component errors and correct application of the SSEC.
3. Assessment/measurement of the skin surrounding the static sources
(e.g., skin waviness, skin splices/joints, access panels, radome fit/fair, and damage).
4. Inspection of the pitot-static probe or static port (e.g., erosion, corrosion, damage, static port orifice degradation, static port step-height, excessive or non-homogenous paint).
5. SmartProbe©. Inspection for corrosion, erosion, damage, and degradation.
A.10.1.2 RVSM-specific maintenance requirements may be necessary to ensure the automatic altitude control and altitude alerting systems meet the requirements of paragraphs A.4.1.3 and A.4.1.4. The data package should provide data to substantiate these requirements, if needed.
A.10.1.3 W here an operating restriction has been adopted (paragraphs A.5.2.2 or A.5.3.3, as appropriate), t he data package should contain the data and information necessary to document and establish that restriction. The Airplane Flight Manual (AFM), Pilot Operating Manual (POM), or an RVSM-specific flight manual supplement must be revised/created as necessary to reflect this restriction.
A.10.1.4 A ny variation/modification from the initial installation affecting RVSM approval should be approved by the airframe manufacturer or approved design organization and allowed by the FAA to show RVSM compliance has not been compromised.
Appendix A A-30
1. ADS modifications. Changes to the components comprising an RVSM-compliant ADS cannot be effectively evaluated without the development of a revised ASE budget. Such modifications must be approved by the airframe manufacturer or approved design organization.
2. Automatic altitude control and altitude alert system modifications.
Changes to components comprising an RVSM-compliant automatic altitude control or altitude alert system should be evaluated by the airframe manufacturer or approved design organization.
3. Altitude reporting. As stated in paragraph A.4.1.2, any transponder meeting or exceeding the requirements of TSO-C74( ) or TSO-C112( ), as applicable, in accordance with the operational regulations under which the airplane is approved.
4. A irframe modifications. Over time, a RVSM-approved aircraft may become a candidate for airframe modifications, such as installation of large antennas, radomes, fairings, equipment lockers, winglets, etc. Any modification changing the exterior contour of the aircraft, or potentially impacting the ADS static sources and/or pneumatic configuration, aircraft weight, and/or performance in any manner, must be evaluated by the manufacturer or design organization to ascertain the RVSM compliance status.
A.10.2 C ontinued Airworthiness Documentation.
A.10.2.1 Aircraft manufacturers. Review and update the following items, as appropriate, to include the effects of RVSM implementation:
1. The Structural Repair Manual (SRM), with special attention to the areas around the static source, angle of attack (AOA) sensors, and doors if their rigging can affect airflow around the previously mentioned sensors.
2. The Master Minimum Equipment List (MMEL).
A.10.2.2 Design organizations. The RVSM airworthiness approval will generally take the form of an RVSM-specific STC. The STC should contain the following:
1. RVSM-specific maintenance instructions for initial and continued airworthiness. These maintenance instructions should include procedures ensuring all sources of ASE and aircraft systems performance degradation can be assessed and controlled.
Paragraphs A.10.1.1, A.10.1.2, and A.10.1.4 summarize key elements of RVSM-specific maintenance procedures.
Appendix A A-31
2. An Airplane Flight Manual Supplement (AFMS). The AFMS should summarize any RVSM-specific performance, configuration, and/or operational considerations (see paragraph A.10.1.3) specific to RVSM performance.
A.10.2.3 T he data package should include the required periodicity of the maintenance procedures presented in paragraph A.10.1.1 and A.10.1.2, to ensure continued airworthiness compliance with RVSM requirements.
A.10.2.4 T he data package should include descriptions of any special procedures not covered in paragraph A.10.1, but may be needed to ensure continued compliance with RVSM requirements.
A.10.2.5 T o the extent possible, define in-flight defect reporting procedures to facilitate identification of ASE sources. Such procedures could cover acceptable differences between primary and alternate static sources, and others as appropriate.
A.11 RVSM Airworthiness Approval.
A.11.1 G eneral . Obtaining RVSM airworthiness approval is a two-step process. First, the manufacturer or design organization develops the data package for airworthiness approval and submits the package to the appropriate ACO. Once the ACO approves the data package, the operator applies the procedures defined in the package to obtain authorization from the appropriate Flight Standards office to use its aircraft to conduct flight in RVSM airspace. The initial airworthiness review process must consider continued airworthiness requirements. This paragraph summarizes the requirements of the RVSM airworthiness approval data package, and presents a means of compliance for a Group or Non-Group aircraft. All aircraft must meet the equipment, configuration, and performance requirements of paragraph A.4, and the altimetry system performance requirements of paragraph A.5.
A.11.2 Contents of the Data Package. As a minimum, the data package should consist of the following items:
1. A definition of the flight envelope(s) appli cable to the subject aircraft. (See paragraph A.2.)
2. A definition of the Group or Non-Group aircraft to which the data package applies. (See paragraph A.3.)
3. The data needed to show compliance with the requirements of paragraphs A.4 and A.5. This data will include most elements presented in paragraphs A.7 through A.9, as appropriate. Older, “ legacy” airframes may require guidance presented in paragraph A.6.
Appendix A A-32
4. The engineering data and compliance procedures required to:
• Validate all aircraft submitted for airworthiness approval meet RVSM requirements; and
• Validate continued in-service RVSM approval integrity of the Group or Non-Group aircraft.
A.11.2.1 Data Package Approval. All necessary data should be submitted to the appropriate ACO for action. The operator will be required to implement the procedures for initial and continued airframe airworthiness compliance, as presented in the approved data package, to demonstrate the aircraft is in compliance with RVSM performance standards.
Appendix B B-1 APPENDIX B. TRAINING PROGRAMS AND OPERATING PRACTICES
AND PROCEDURES B.1 Introduction. Items listed in this appendix should be standardized and incorporated into training programs and operating practices and procedures. Certain items may already be adequately standardized in existing operator programs and procedures. New technologies may also eliminate the need for certain crew actions. If this is the case, then the intent of this guidance can be considered to be met.
Note: This AC was written for use by a wide variety of operator types (e.g., 14 CFR parts 91, 91K, 121, 125, 129, and 135 operators); therefore, certain items are included for purposes of clarity and completeness.
B.2 RVSM General.
B .2.1 RVSM Description. RVSM airspace was designed to allow 1,000 ft vertical separation between aircraft operating at flight levels (FL) at or above FL 290. At 0901 universal coordinated time (UTC) on January 20, 2005, the FAA implemented RVSM between FL 290−410 (inclusive) in the following airspace: the airspace of the lower 48 states of the United States, Alaska, Atlantic, and Gulf of America High Offshore Airspace, and the San Juan flight information region (FIR). On the same time and date, RVSM was also introduced into the adjoining airspace of Canada and Mexico to provide a seamless environment for aircraft traversing those borders. In addition, RVSM was implemented on the same date in the Caribbean and South American regions.
B.2.1.1 In the domestic Un ited States, Alaska, offshore airspace, and the San Juan FIR RVSM airspace, altitude assignments for direction of flight follow a scheme of odd altitude assignment for magnetic courses 000−179 degrees and even altitudes for magnetic courses 180−359 degrees for flights up to and including FL 410, as indicated in Figure B-1.
Figure B-1. Flight Level Orientation Scheme + Note: Odd flight levels (FL): magnetic course 000−179 degrees.
Even FLs: magnetic course 180−359 degrees.
Appendix B B-2 B.3 Operating Policies and Procedures in U.S.-Controlled RVSM Airspace. Operators and pilots should reference the U.S. Aeronautical Information Manual (AIM), Chapter 4, Section 6, Operational Policy/Procedures for Reduced Vertical Separation Minimum (RVSM) in the Domestic U.S., Alaska, Offshore Airspace and the San Juan FIR, and the U.S. Aeronautical Information Publication (AIP), En Rout e Sec tion 7, Oceanic Operations, as applicable, prior to conducting RVSM operations in U.S.-controlled RVSM airspace.
B.3.1 Flight Planning. During flight planning, the flightcrew and dispatchers, if applicable, should pay particular attention to conditions which may affect operation in RVSM airspace. These include, but may not be limited to:
1. V erifying the aircraft and operator meet RVSM requirements.
2. Annotating the flight plan to be filed with the Air Traffic Service Provider (ATSP) to show compliance for RVSM operations. The International Civil Aviation Organization (ICAO) flight plan, FAA Form 7233-4, Pre-F light Pilot Checklist and International Flight Plan, Item 10, Equipment, should be annotated with the letter W for filing in RVSM airspace.
• W hen using FAA Form 7233- 4, operators should ensure that the aircraft’s registration number (Reg/) is listed in Item 18 (Other Information), if different than that listed in Item 7 (Aircraft Identification).
• For exceptions to the use of FAA Form 7233-4, refer to the FAA AIM, Chapter 5, Air Traffic Procedures, for the proper flight codes.
Note: An aircraft or operator not meeting the requirements for RVSM operations including an aircraft without operable RVSM equipment is referred to as non-RVSM. If either the flightcrew or aircraft do not meet the requirements for RVSM, the operator or dispatcher will not file the RVSM equipment code in the flight plan and follow the procedures for a non-RVSM status, including the appropriate pilot-air traffic control (ATC) phraseology in Table B-1, RVSM Phraseology.
3. Reported and forecast weather conditions on the route of flight.
4. Minimum equipment requirements pertaining to altitude-keeping systems.
5. Traffic Alert and Collision Avoidance System (TCAS) equipage. TCAS equipage requirements are contained in part 121, § 121.356; part 125, § 125.224; part 129, § 129.18; and part 135, § 135.180. Part 91 appendix G does not contain TCAS equipage requirements specific to RVSM; however, part 91 appendix G does require that aircraft equipped with TCAS II and flown in RVSM airspace be modified to incorporate TCAS II Version 7.0 or a later version.
6. If re quired for the specific aircraft Group, accounting for any aircraft operating restrictions related to RVSM airworthiness approval. (See Appendix A, RVSM Airworthiness Certification, paragraph A.10.1.3.)
Appendix B B-3 B.3.2 Preflight Procedures. Accomplish the following actions during preflight:
1. Review maintenance logs and forms to ascertain the condition of equipment required for flight in the RVSM airspace. Ensure maintenance action has been taken to correct defects to required equipment.
2. During the external inspection of aircraft, pay particular attention to the condition of static sources, the condition of the fuselage skin near each static source, and any other component affecting altimetry system accuracy. (A qualified and authorized person other than the pilot (e.g., a Flight Engineer (FE) or maintenance personnel) may perform this check.)
3. Before takeoff:
• The aircraft altimeters should be set to the barometric pressure for local altimeter setting (QNH) and should display a known elevation (e.g., field elevation) within the limits specified in aircraft operating manuals. The difference between the known elevation and the elevation displayed on the altimeters should not exceed 75 ft.
• The two primary altimeters should also agree within limits specified by the aircraft operating manual/Airplane Flight Manual (AFM), as applicable. An alternative procedure using atmospheric pressure at aerodrome elevation (QFE) may also be used.
Note: Both checks should be an emphasis item for training materials.
4. Equipment required for flight in RVSM airspace should be operational, and indications of malfunction should be resolved.
B.3.3 Procedures Before RVSM Airspace Entry. If any of the required equipment fails prior to the aircraft entering RVSM airspace, the pilot should request a new clearance to avoid flight in this airspace. The following equipment must be operating normally at entry into RVSM airspace:
1. Two primary altitude measurement systems.
2. O ne automatic altitude control system.
3. One altitude alerting device.
Note: The operator or pilot should ascertain the requirement for an operational transponder and TCAS in each RVSM area where operations are intended.
B.3.4 In-Flight Procedures. Inc orporate the following policies into flightcrew training and procedures, as applicable:
1. Flightcrews should comply with aircraft operating restrictions (if required for the specific aircraft Group) related to RVSM airworthiness approval. (See paragraph A.10.1.3.)
Appendix B B-4
2. Place emphasis on promptly setting the sub-scale on all primary and standby altimeters to 29.92 inches of mercury (inHg)/1013.25 hectopascals (hPa) when climbing through the transition altitude and rechecking for proper altimeter setting when reaching the initial cleared flight level (CFL).
3. In level cruise, it is essential the aircraft is flown at the CFL. This requires particular care is taken to ensure ATC clearances are fully understood and followed. Except in contingency or emergency situations, the aircraft should not intentionally depart from CFL without a positive clearance from ATC.
4. During cleared transition between FLs, the aircraft should not be allowed to overshoot or undershoot the CFL by more than 150 ft (45 m).
Note: It is recommended the level-off be accomplished using the altitude capture feature of the automatic altitude control system, if installed.
5. An automatic altitude control system must be operative and engaged during level cruise, except when circumstances such as the need to retrim the aircraft or turbulence require disengagement. In any event, adherence to cruise altitude should be done by reference to one of the two primary altimeters.
6. The altitude alerting system must be operational.
7. At cruise FL, the two primary altimeters should agree within 200 ft (60 m) or a lesser value if specified in the aircraft operating manual. (Failure to meet this condition will require that the altimetry system be reported as defective and notified to ATC.) Note the difference between the primary and standby altimeters for use in contingency situations.
8. At intervals of approximately 1 hour, make cross-checks between the primary altimeters and the standby altimeter.
a. The normal pilot scan of flight deck instruments should suffice for altimeter cross-checking on most flights.
b. When operating in surveillance airspace (Radar/Automatic Dependent Surveillance-Broadcast (ADS-B)), the initial altimeter cross-check should be performed after level-off.
c. In oceanic and remote continental (procedural) airspace, a cross-check should be performed and recorded in the vicinity of the point where oceanic and remote continental navigation begins (e.g., on coast out). The readings of the primary and standby altimeters should be recorded and available for use in contingency situations.
d. Some aircraft have automatic comparators that compare the two primary altimetry systems. The comparators include a monitoring, warning, and fault function. The faults may be recorded automatically by the system, but a record of the differences in the primary altimetry systems may not be easily derived.