Appendix A A-25 D.1.5.3 required reassessment. This item states, “Each individual aircraft in the Group must be built to have ASE contained within ±200 ft.” This statement 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 considering the risk analysis allows for a small proportion of aircraft to exceed 200 ft. 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 actual 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 paragraph A.7.2.1.1 through A.7.2.1.5 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 Example 1. Group Aircraft.
A.9.1.1.1 One process for showing compliance with RVSM requirements is shown in Figure A.9-1, Process for Showing Initial and Continued Compliance of Airframe Static Pressure System. Figure A.9-1 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 every Mth
Appendix A A-26 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.9.1.1.2 There are various ways in which the flight test and inspection data might be used to establish the correlation. The example shown in Figure A.9-2 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.9.1.1.1 above.
A.9.1.1.3 The method illustrated in Figures A.9-1 and A.9-2 is appropriate for new models since it does not rely on any preexisting database for the Group.
A.9.1.2 Example 2. Group Aircraft. Figure A.9-3, 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-Group 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.9-1. 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.9-2. Compliance Demonstration Ground-To-Flight Test Correlation Process Example Conduct ADC ground Measure fuselage Fuselage flight test calibration conformance geometric conformance geometric calibration using inspection with xx ? Yes tool No Perform an Remove ADC calibration Rework analysis to estimate error airplane position error Residual Position Error Correlation 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.9-3. 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) * Certification Cards. Demonstration * Establish the SSEC Laws for the of compliance with requirements. Air Data Computers. 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 NOT Theoretical Analysis.
Satisfactory?
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 General. 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 Define 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. Air Data System 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. Skin waviness, skin splices/joints, access panels, radome fit/fair, and damage.
4. Inspection of the pitot-static probe or static port. Erosion, corrosion, damage, static port orifice degradation, static port step-height, excessive or non-homogenous paint.
5. SmartProbe©. Inspection for corrosion, erosion, damage, 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 Where an operating restriction has been adopted, paragraphs A.5.2.2 or A.5.3.3, as appropriate, the data package should contain the data and information necessary to document and establish that restriction. The AFM, pilot operating manual, or a RVSM-specific flight manual supplement must be revised/created as necessary to reflect this restriction.
A.10.1.4 Any 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. Air Data System Modifications. Changes to the components comprising an RVSM-compliant air data system 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 Technical Standard Order (TSO) C74( ), TSO C112( ), as applicable, in accordance with the operational regulations under which the airplane is approved.
4. Airframe 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 air data system 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 Continued 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 with special attention to the areas around the static source, angle of attack 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 a 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 (paragraph A.10.1.3) specific to RVSM performance.
A.10.2.3 The 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 The 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 To 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 General. Obtaining RVSM airworthiness approval is a two-step process. First, the manufacturer or design organization develops the data package through which to seek airworthiness approval and submits the package to the appropriate ACO for approval.
Once the ACO approves the data package, the operator applies the procedures defined in the package to obtain authorization from the Flight Standards District Office (FSDO)/certificate-holding district office (CHDO)/certificate management office (CMO)/International Field Office (IFO) (as appropriate) 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.
A.11.2.1 As a minimum, the data package should consist of the following items:
1. A definition of the flight envelope(s) applicable to the subject aircraft. See paragraph A.2.
2. A definition of the aircraft 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.11.2.2 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 advisory circular (AC) was written for use by a wide variety of operator types (e.g., 14 CFR part 91, 91K, 121, 125, 129, 135 operators) and therefore, certain items are included for purposes of clarity and completeness.
B.2 Flight Planning. During flight planning, the flightcrew and dispatchers, if applicable, should pay particular attention to conditions which may affect operation in Reduced Vertical Separation Minimum (RVSM) airspace. These include, but may not be limited to:
1. Verifying the aircraft is approved for RVSM operations.
2. Annotating the flight plan to be filed with the Air Traffic Service Provider to show the aircraft and operator are authorized for RVSM operations. Block 10 (equipment) of the International Civil Aviation Organization (ICAO) flight plan (FAA Form 7233-4) should be annotated with the letter W for filing in RVSM airspace.
3. For exceptions to the use of FAA Form 7233-4, see chapter 5 of the latest version of the FAA Aeronautical Information Manual (AIM) for the proper flight codes.
Note: An aircraft or operator not authorized for RVSM operations or an operator/aircraft without operable RVSM equipment is referred to as non-RVSM.
If either the operator or the aircraft or both have not received RVSM authorization the operator or dispatcher will not file the RVSM equipment code in the flight plan.
4. Reported and forecast weather conditions on the route of flight.
5. Minimum equipment requirements pertaining to height-keeping systems.
6. If required for the specific aircraft group, accounting for any aircraft operating restrictions related to RVSM airworthiness approval. (See Appendix A, paragraph A.10.1.3.)
B.3 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.
Appendix B B-2
2. During the external inspection of aircraft, pay particular attention to the condition of static sources and 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 local altimeter atmospheric pressure at nautical height (QNH) setting 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 field elevation (QFE) may also be used.
Note: Both checks should be an emphasis item for training materials.
4. Before takeoff, equipment required for flight in RVSM airspace should be operational, and indications of malfunction should be resolved.
B.4 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 so as to avoid flight in this airspace. The following equipment should be operating normally at entry into RVSM airspace:
1. Two primary altitude measurement systems.
2. One automatic altitude-control system.
3. One altitude-alerting device.
Note: The operator should ascertain the requirement for an operational transponder in each RVSM area where operations are intended.
B.5 In-Flight Procedures. Incorporate the following policies into flightcrew training and procedures:
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.)
2. Place emphasis on promptly setting the sub-scale on all primary and standby altimeters to 29.92 in. Hg/1013.25 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 air traffic control (ATC) clearances are fully
Appendix B B-3 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 flight levels, the aircraft should not be allowed to overshoot or undershoot the cleared flight level 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 should 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 should be operational.
7. At cruise flight level 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 stand by altimeters for use in contingency situations.
8. At intervals of approximately 1 hour, make cross-checks between the primary altimeters and the stand-by altimeter.
• The normal pilot scan of flight deck instruments should suffice for altimeter crosschecking on most flights.
• When operating in surveillance airspace (Radar/Automatic Dependent Surveillance-Broadcast (ADS-B)), the initial altimeter cross-check should be performed after level off.
• 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.
• 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.
Note: In oceanic and remote continental (procedural) airspace, even if the aircraft is equipped with automatic comparators, the crew should be recording the altimeter cross-checks for use in a contingency situation.
9. Normally, the altimetry system being used to control the aircraft should be selected to provide the input to the altitude-reporting transponder transmitting information to ATC.
Appendix B B-4
10. If ATC notifies the pilot of an assigned altitude deviation (AAD) error equal to or exceeding 300 ft (90 m) then the pilot should take action to return to cleared flight level (CFL) as quickly as possible.
11. Contingency procedures after entering RVSM airspace. The flight crew after realizing that they no longer can comply with RVSM requirements (aircraft system failure, weather, lost com, etc.) must request a new clearance from the controller/radio operator as soon as the situation allows. If a new clearance is not available or the nature of the emergency requires rapid action the pilot should notify ATC of their action and contingency procedures. Operators should refer to the RVSM section of the AIM when experiencing abnormal situations and implementing contingency procedures. It is also the responsibility of the crew to notify ATC when the implementation of the contingency procedures is no longer required.
B.6 Post Flight. In making maintenance logbook entries against malfunctions in height-keeping systems, the pilot should provide sufficient detail to enable maintenance to effectively troubleshoot and repair the system. The pilot should detail the actual defect and the crew action taken to try to isolate and rectify the fault. Note the following information when appropriate:
1. Primary and standby altimeter reading.
2. Altitude selector setting.
3. Subscale setting on altimeter.
4. Autopilot used to control the airplane and any differences when the alternate system was selected.
5. Differences in altimeter readings if alternate static ports selected.
6. Use of air data computer selector for fault diagnosis procedure.
7. Transponder selected to provide altitude information to ATC and any difference if alternate transponder or altitude source is manually selected.
B.7 Special Emphasis Items: Flightcrew Training. The following items should also be included in flightcrew training programs:
1. Operators are responsible for knowing the RVSM procedures in the areas of intended operation. Operators starting RVSM operation in an RVSM area of operation new to them should ensure their RVSM programs incorporate RVSM policy and procedures unique to the new area of operations.
Note: Additional specific information on RVSM operational policy and procedures in the domestic U.S., Alaska, Offshore Airspace, and the San Juan flight information region (FIR) can be found in the AIM, Chapter 4, Section 6.
2. Importance of crewmembers cross-checking each other to ensure ATC clearances are promptly and correctly complied with.