Reference (E) - RVSM FRD.pdf

Naval Air Systems Command

Functional Requirements Document for

Reduced Vertical Separation Minimum (NAVAIR FRD for RVSM) Revision A

(Change 1)

15 January 2021

NAVAIR Public Release 2021-229 Distribution Statement A – Approved for public release;

distribution is unlimited.

i

THIS PAGE INTENTIONALLY BLANK

ii

FUNCTIONAL REQUIREMENTS DOCUMENT FOR REDUCED

VERTICAL SEPARATION MINIMUM (FRD FOR RVSM)

PROGRAM TITLE:

COMMUNICATIONS/NAVIGATION/SURVEILLANCE/

AIR TRAFFIC MANAGEMENT (CNS/ATM)

PREPARED BY:

Ashley Bird, RVSM/NAV Engineer PMA209

BASELINE FRD DATE:

FRD Revision A:

FRD Revision A Change 1:

7 January 2003 14 November 2014 15 January 2021

M. V. WILSON, CAPT, USN

Date Released iii

CHANGE SUMMARY PAGE

This change summary page is provided to maintain a record of change to the last issue of the Functional Requirements Document (FRD). Upon receipt of a change or revision, the holder of the FRD should incorporate the change(s)/revision(s) into the original and make an appropriate entry on the Record of Change listing below:

RECORD OF CHANGE

CHANGE NO. DATE TITLE OR BRIEF DESCRIPTION

(List of Change Pages)

ENTERED BY:

Initial Issue

Revision A

7 January 2003

14 November

Document baseline (under formal PMA209 Configuration Control)

Title Page-Document changed to NAVAIR document. All references to OPNAV as promulgator are removed.

Page ii- Added signature page.

Page v, Executive Summary – Added Figure 1 reference in first paragraph, deleted second paragraph because Rev A now addresses all three RVSM requirements categories, changes N78 to N98, and minor revisions to the last paragraph.

Pages vi-vii- Table of Contents– Updated page numbering.

Entire document outline converted to decimal outline format.

Page 1-1.2 Scope – Scope now includes all categories of requirements of RVSM.

Page 2-1.2.4 – Identified requirements terminology paragraph.

Pages 1-2-Background-deleted unnecessary text and revised for clarification.

Page 3- Figure 1 – Changed from Global RVSM Figure to Flight Level RVSM Figure.

Page 5-Added Reference (c). NAVAIR INST 5400.160A Air Combat Electronics PMA209 Charter Paragraph

7. S.

Removed reference (f) CNAF MSG R

061534Z JAN 05, ZYB PSN

495169Q34, 6 January 2005 (expired).

Pages 6-7-Rewrote paragraph 3.1 adding subparagraphs 3.1.1 for dual and 3.1.2 for single altimetry RVSM equipage.

DOD-FAA permits tactical fighter and

Mr. Berk C. Hoover, IPTL

Anthony Singleton, IPTL iv bomber aircraft to fly RVSM with single qualified altimetry systems.

Page 9-Added Figure 3 for single altimetry RVSM. This figure describes a single altimetry system.

Page 10-Paragraph 3.2.3, Added requirement for aircraft to meet performance requirement of the Basic envelope. Added statement that the aircraft would not be certified to the Full Envelope. All aircraft being qualified for RVSM must qualify the basic envelope. The full envelope is not certified in civil/commercial aircraft.

Page 11 – Figure 4. Updated figure to display notional RVSM envelopes in sub-MACH range only.

Pages 14-15-Added RVSM Inspection Program. 14 CFR, Part 91, Appendix G, Section 3. (b) (1) (i). Maintenance Programs, Periodic inspections and other maintenance practices are required.

Changed Ref. 2.1.b to 2.1.b.

Pages 15-17 - Added RVSM Monitoring Program including Table 1 for RVSM Monitoring Plan. FAA AC 91-86 paragraph 12. d. (8).

Page 16 – 3.7.3.2 & 3.7.3.2.1. Removed SHALL from both paragraphs.

Removed Coast Guard.

Page 16-paragraph 3.7.3-Changed SHALL to should.

Page 21-OPNAV changed to PMA209.

Page 40-Removed Appendix E-The definitions of basic and full envelope were moved to section 3, paragraph 3.2.3-(This was done because the flight envelopes are requirements).

Revision A Change 1

15 January 2021 Title page - rolled revision number, date and changed to Distro A.

Page ii – updated for new signature Page vi – corrected references Page vii-viii – updated Table of Contents Page 4 – Revised to address removal of previous Appendix C Page 19 – Appendix A – Acronyms, deleted unused and added missing acronyms Page 21 – Appendix B – Glossary, deleted and corrected terms

Ashley Bird, RVSM/NAV Engineer v

Removed previous Appendix C and re-lettered ASE Components as Appendix C.

Corrected references throughout entire document.

COMMENT INFORMATION

This document is under Configuration Management Control at NAVAIR, PMA209 Patuxent River, MD. Comments and suggested changes and updates to the document should be addressed to the following NAVAIR, PMA209, Configuration Management Control Point:

Send to: NAVAIRSYSCOM Attn.:PMA209 CNS/ATM 47123 Buse Rd.

Bldg. 2272, Suite 350 Patuxent River, MD 20670 Fax No.: 301-757-6459 vi

EXECUTIVE SUMMARY

During the 1980’s the International Civil Aviation Organization (ICAO) Review of the General Concept of Separation Panel (RGCSP) (ref. a) completed a comprehensive series of studies to examine the feasibility of reducing the Vertical Separation Minimum (VSM) above Flight Level (FL) 290 from 2000 ft to 1000 ft (Figure 1). The results of these studies demonstrated that the reduction of vertical separation was safe, cost beneficial, and feasible without imposing unduly demanding technical requirements.

Reduced Vertical Separation Minimum (RVSM) is being applied in selected airspace throughout the world to achieve capacity and operational benefits. RVSM approval is not restricted to a specific region or airspace as the aircraft requirements are the same globally. There are three categories of requirements for RVSM approval:

1. RVSM Equipage and Performance Requirements

2. RVSM Inspection Plan

3. RVSM Monitoring Program

This Functional Requirements Document (FRD) establishes the minimum functional requirements needed for Navy and Marine Corps aircraft to conform to civil airspace RVSM requirements.

However, it should be understood that this FRD does not usurp any international agreements or treaties that pertain to “State Owned Aircraft” being operated in accordance with rules governing Operational Air Traffic (OAT) that may differ from civil airspace requirements.

Due to the design limitations of Naval tactical aircraft and trainers, most of naval aviation will not be retrofitted with RVSM equipage, as determined by Deputy Chief of Naval Operations for Air Warfare (N98). The Department of Defense (DoD) is encouraged to make military aircraft compliant, as far as practicable, particularly transport and tanker aircraft that operate at FL 290 and above. Although RVSM airspace is exclusionary, the Federal Aviation Administration (FAA) will accommodate non-RVSM compliant U.S. military aircraft within the Domestic Reduced Vertical Separation Minimum (DRVSM) airspace, without mission degradation, to the extent practicable based upon existing traffic and safety considerations.

The Program Manager Air for Air Combat Electronics (PMA209) is designated as the Navy Lead Program Office to coordinate Communication Navigation Surveillance / Air Traffic Management (CNS/ATM) efforts as recommended by N78 Letter (CNO Ser 7U660859 dated 14 October 1997) (ref. b). In accordance with this tasking, PMA209 has developed this FRD for RVSM, Revision A Change 1. PMA209 is tasked in accordance with Communication Navigation Surveillance / Air Traffic Management Requirements, Functional Requirements Document Update and Certification Process Update, Memorandum for the Record of 24 January 2020 (ref. c) as the certification authority for approved CNS/ATM functionalities.

Ref: Federal Aviation Administration Advisory Circular (FAA AC) 91-85 (Navy modified) (ref. e).

vii

TABLE OF CONTENTS

1.0 INTRODUCTION 1

1.1 PURPOSE

1.2 SCOPE

1.3 BACKGROUND

1.4 MILITARY AIRCRAFT

2.0 REFERENCE DOCUMENTS 5

3.0 REQUIREMENTS

3.1 AIRCRAFT EQUIPAGE

3.2 ALTIMETRY

3.3 ALTITUDE ALERTING

3.4 AUTOMATIC ALTITUDE CONTROL SYSTEM

3.5 TRAFFIC ALERT AND COLLISION AVOIDANCE SYSTEM CAPABILITY

3.6 RVSM INSPECTION PLAN

3.7 RVSM MONITORING PLAN

3.7.1 PURPOSE

3.7.2 RESPONSIBILITIES FOR RVSM MONITORING

APPENDIX A. ACRONYMS 19

APPENDIX B. GLOSSARY 21

APPENDIX C. ALTIMETRY SYSTEM ERROR COMPONENTS 24

C.1.0 INTRODUCTION 24

C.2.0 OBJECTIVE OF ALTIMETRY SYSTEM ERROR BUDGET 24

C.3.0 ALTIMETRY SYSTEM ERROR 24

viii

LIST OF FIGURES

Figure 1. RVSM Levels Figure 2. Notional Architecture of RVSM Compliant Dual Altimetry System Figure 3. Notional Architecture of RVSM Compliant Single Altimetry System Figure 4. Notional RVSM Basic and Full Envelopes Figure C.3-1. Altimetry System Errors Figure C.3-2 Static Source Error/Static Source Error Correction

LIST OF TABLES

Table 1. Naval Tactical Group Designation and Monitoring Requirements Table C.3-1 Static Source Error (Cause: Aerodynamic Disturbance to Free-Stream Conditions) Table C.3-2 Residual Static Source Error

1.0 INTRODUCTION

1.1 PURPOSE

This document provides the minimum functional requirements for Navy and Marine Corps aircraft altimetry and height keeping for conducting flights in airspace or on routes where Reduced Vertical Separation Minimum (RVSM) is applied. Compliance with this document will ensure aircraft meet the performance requirements of CFR Part 91, Appendix G (ref. d).

1.2 SCOPE

The Chief of Naval Operations (CNO) has defined three categories of requirements for RVSM:

1.2.1. RVSM Equipage and Performance Requirements

1.2.2. RVSM Inspection Plan

1.2.3. RVSM Monitoring Program

1.2.4. Requirements Terminology. Within this document, the term “shall” is used to indicate requirements. An approved design should comply with every requirement, which can be assured by inspection, test, analysis or demonstration. The term “must” is used to identify items which are important but are either duplicated somewhere else in the document as a “shall”, or are considered outside of the scope of this document. The term “should” is used to denote a recommendation, but does not constitute a requirement.

Ref: FAA AC 91-85

1.3 BACKGROUND

During the 1980’s the International Civil Aviation Organization (ICAO) Review of the General Concept of Separation Panel (RGCSP) completed a comprehensive series of studies to examine the feasibility of reducing the Vertical Separation Minimum (VSM) above FL 290 from 2000 ft to 1000

ft. The results of these studies demonstrated that the reduction of vertical separation was safe, cost beneficial, and feasible without imposing unduly demanding technical requirements.

The ICAO RGCSP published two reports that have provided the basis for the development of RVSM implementation documents. The major conclusions of the Report of RGCSP/6 (ref. a) were that:

1.3.1 RVSM is "technically feasible without imposing unreasonably demanding technical requirements on the equipment."

1.3.2 RVSM would provide "significant benefits in terms of economy and en route airspace capacity."

The second major report published by RGCSP was the Report of RGCSP/7 (ref. e). This report contains the draft "Manual on Implementation of a 300 m (1,000 ft) Vertical Separation Minimum

(VSM) Between FL 290 and 410 Inclusive." This material was approved by the ICAO Air Navigation Commission in February 1991 and published as ICAO Document 9574 (ref. f) in 1992. It provides guidance for RVSM implementation planning, airworthiness requirements, flight crew procedures, Air Traffic Control (ATC) considerations, and system performance monitoring.

Document 9574 was used to derive the Minimum Aircraft Systems Performance Specifications (MASPS) used by designers, manufacturers, operators, and approval authorities. There have been two MASPS documents developed for the U.S. and Europe, respectively: FAA AC 91-85, Authorization of Aircraft and Operators for Flight in Reduced Vertical Separation Minimum Airspace (ref. g) and Joint Airworthiness Authorities (JAA) Temporary Guidance Leaflet 6 REV 1, Guidance Material on the Approval of Aircraft and Operators for Flight in Airspace Above Flight Level 290 where a 300 m (1,000 ft) Vertical Separation Minimum is Applied (ref. h). These documents detail the civil airworthiness, continuing airworthiness, and operations programs necessary to approve civil operators and aircraft to conduct flights in RVSM airspace. The Original Equipment Manufacturer (OEM), the integrating contractor, or a qualified government test organization may perform testing and demonstration of RVSM compliance.

It is Department of Defense (DoD) policy that military platforms conducting peacetime operations will conform to applicable rules to ensure interoperability and transparency within domestic and international controlled airspace. The U.S. Navy and U.S. Marine Corps will self-certify the tactical aircraft that will enter RVSM airspace. Adopting and following the civil monitoring requirements will ensure the transparency needed to instill confidence that naval aviation is compliant and safe to fly in a RVSM environment.

Non-RVSM Airspace RVSM Airspace

FL 430

FL 410

FL 390

FL 370

FL 350

FL 330

FL 310

FL 290

FL 280

FL 270

GREEN = EASTBOUND LEVELS

Non-RVSM Above 41,000 feet (Flight Level (FL) 410)

FL 410

FL 400

FL 390

FL 380

FL 370

FL 360

FL 350

FL 340

FL 330

FL 320

FL 310

FL 300

FL 290

Non-RVSM Below 29,000 feet (Flight Level (FL) 290)

RED = WESTBOUND LEVELS

Figure 1. RVSM Levels

1.4 MILITARY AIRCRAFT

Due to the design limitations, most Navy and Marine Corps aircraft will not be retrofitted with RVSM equipage, as determined by Chief of Naval Operations Letter Serial Number N783C2/4U789215, dated 1 June 2004 (ref. i). Civil Air Traffic service providers have stated they will accommodate military aircraft that do not meet RVSM functionality to the extent practicable upon existing traffic and safety considerations.

The goal of Domestic RVSM (DRVSM) is to achieve more advantageous flight profiles with increased airspace capacity. The DoD has been encouraged to make military aircraft compliant with the RVSM MASPS as far as practicable, particularly transport and tanker aircraft that operate at FL 290 and above

Although RVSM airspace is exclusionary, the FAA assures that they will accommodate non-RVSM compliant military aircraft operation within DRVSM airspace, without mission degradation, to the extent practicable based upon existing traffic and safety considerations. State aircraft that will not be equipped for RVSM will be afforded 2000 ft separation when operating above FL 290. In Europe, formation flights of State aircraft, regardless of their individual RVSM approval status, are treated as non-RVSM and are provided with 2000 ft vertical separation.

Controllers must be continually aware of the RVSM status of all aircraft operating with DRVSM airspace. Though advance notification for non-RVSM equipped aircraft flight planning to operate within DRVSM airspace is not required, flight plans will need to indicate RVSM equipage status.

Additionally, the DoD is responsible for ensuring that flight crews are aware of the operating practices and procedures in FAA Advisory Circular (AC) 91-85, Appendix 4 (ref. g), for aircraft operations above FL 290, regardless of RVSM equipage status.

The FAA has agreed to recognize DoD aircraft equipped with a single RVSM compliant altitude measurement system for DRVSM. However, such aircraft must meet the height keeping performance required by all RVSM-compliant aircraft. It should be noted that this does not mean single altimeter aircraft will be authorized to fly as RVSM-compliant in other RVSM airspace.

2.0 REFERENCE DOCUMENTS

a. Doc. 9536, Review of the General Concept of Separation Panel (RGCSP), Sixth Meeting, Montreal, 28 November - 15 December 1988

b. Chief of Naval Operations (N78) Letter Serial Number N880G2/7U660859, dated 14 October

1997, Platform Integration Study for Global Air Traffic Management (GATM)

c. Communication Navigation Surveillance / Air Traffic Management Requirements, Functional Requirements Document Update and Certification Process, Memorandum for the Record of 24 January 2020

d. Electronic Code of Federal Regulations Title 14 Part 91 Appendix G.

http://www.ecfr.gov/cgi-bin/text-idx?node=14:2.0.1.3.10#se14.2.91_1706

e. Doc. 9572, RGCSP, Seventh Meeting, Montreal, 30 October - 20 November 1990

f. Doc. 9574, Manual on the Implementation of a 300 m (1,000 ft) Vertical Separation Minimum

Between FL 290 - FL 410 Inclusive, Second Edition, 2001

g. FAA Advisory Circular 91-85, Authorization of Aircraft and Operators for Flight in Reduced

Vertical Separation Minimum Airspace, 21 August 2009

h. Joint Aviation Authorities (JAA) Temporary Guidance Leaflet No. 6, Revision 1: Guidance

Material on the Approval of Aircraft and Operators for Flight in Airspace Above Flight Level 290 Where a 300 m (1,000 ft) Vertical Separation Minimum is Applied, 1 October 1999

i. Chief of Naval Operations (N78) Letter Serial Number N783C2/4U789215, dated 1 June 2004, CNO Reduced Vertical Separation Minimums (RVSM) Guidance

j. PMA209 CNS/ATM Reduced Vertical Separation Minimum (RVSM) Periodic Monitoring Policy, Revision A of 14 July 2015

k. COMNAVAIRFORINST 13200.1 Reduced Vertical Separation Minimum (RVSM) Periodic Monitoring, 20 October 2009 http://www.ecfr.gov/cgi-bin/text-idx?node=14:2.0.1.3.10#se14.2.91_1706

3.0 REQUIREMENTS

The requirements of this FRD are applicable to all Naval tactical aircraft seeking RVSM approval.

The Navy’s civil derivative aircraft apply for approval in accordance with the policies required to update their Type Certificate.

3.1 AIRCRAFT EQUIPAGE

For RVSM operations, the minimum equipment required shall be in accordance with the following paragraphs for all aircraft.

3.1.1 Dual altimetry equipped aircraft shall have the following.

3.1.1.1 Two independent altitude measurement systems (see Figure 2).

3.1.1.2 Cross-coupled static source/system, with ice protection if located in areas subject to ice accretion.

3.1.1.3 Equipment for measuring static pressure sensed by the static source, converting it to pressure altitude, and displaying the pressure altitude to the flight crew.

3.1.1.4 Equipment for providing a digitally coded signal corresponding to the displayed pressure altitude, for automatic altitude reporting purposes.

3.1.1.5 Static Source Error Correction (SSEC), if needed to meet the performance requirements of paragraphs 3.2.2, as appropriate.

3.1.1.6 The equipment fit shall provide reference signals for automatic control and alerting at the selected altitude. These signals shall be derived from an altitude measurement system meeting the full requirements of this document, but must in all cases enable the requirements of paragraphs 3.2.5, 3.2.6.1 and 3.3 to be met.

3.1.2 Single altimetry equipped aircraft shall have the following. (See Figure 3)

3.1.2.1 An altitude measurement system.

3.1.2.2 Cross-coupled static source/system, with ice protection if located in areas subject to ice accretion.

3.1.2.3 Equipment for measuring static pressure sensed by the static source, converting it to pressure altitude, and displaying the pressure altitude to the flight crew.

3.1.2.4 Equipment for providing a digitally coded signal corresponding to the displayed pressure altitude, for automatic altitude reporting purposes.

3.1.2.5 SSEC, if needed to meet the performance requirements of paragraphs 3.2.2, as appropriate.

3.1.2.6 The equipment fit shall provide reference signals for automatic control and alerting at the selected altitude. These signals shall be derived from an altitude measurement system meeting the full requirements of this document, but must in all cases enable the requirements of paragraphs 3.2.5, 3.2.6.1 and 3.3 to be met.

Additional information: Tactical aircraft certified with single certifiable altimetry systems are authorized for DRVSM where approved by PMA209 certification letter and PMA class desk fleet release. Aircrew members must verify approval prior to flight.

Ref: FAA AC 91-85, Para. 9a(1) (Amended)

3.1.3 One Secondary Surveillance Radar (SSR) altitude reporting transponder. If only one is fitted, it shall have the capability for switching to operate from either altitude measurement system.

Ref: FAA AC 91-85 Para. 9a(2) (Amended)

3.1.4 An altitude alerting system.

Ref: FAA AC 91-85 Para. 9a(3) (Amended)

3.1.5 An automatic altitude control system.

Ref: FAA AC 91-85 Para. 9a(4) (Amended)

Figure 2. Notional Architecture of RVSM Compliant Dual Altimetry System

Figure 3. Notional Architecture of RVSM Compliant Single Altimetry System

3.2 ALTIMETRY

3.2.1 System Definition

The altimetry system of an aircraft comprises all those elements involved in the process of sampling free stream static pressure and converting it to a pressure altitude output. The elements of the altimetry system fall into two main groups:

3.2.1.1. Airframe plus static sources.

3.2.1.2. Avionics and/or instruments.

Ref: FAA AC 91-85 Para. 9b(1)

3.2.2 Altimetry System Accuracy

Accuracy is determined by the Altimetry System Error (ASE). This is the difference between the pressure altitude displayed to the flight crew when referenced to International Standard Atmosphere (ISA) standard ground pressure setting (29.92 in. Hg/1013.25 hPa) and free stream

Mission Computer

Digital FCC or ADC

Ps - Static

Pt - Pitot Standby Altimeter

Head Up Display Autopilot

340 29000

340 29000

1.5 M 0.84 G 1.0

4.0

Mission Computer

Digital FCC or ADC

Ps - Static

Pt - Pitot Standby Altimeter

Head Up Display Autopilot

340 29000340 29000

340 29000

1.5 M 0.84 G 1.0

4.0

340 29000

1.5 M 0.84 G 1.0

4.0 pressure altitude. An overview of ASE and its components is provided in Appendix C. Specific ASE requirements are dependent on whether an aircraft has a group or non-group designation.

3.2.2.1 For efficiency of aircraft certification and testing, aircraft may be considered as a group. Group aircraft shall have been manufactured to a nominally identical design and be approved by the same Type Certificate (TC) or DoD contract specification as applicable.

Performance of these aircraft within the flight envelope defined for a particular group is expected to be similar. (Threshold = Objective)

3.2.2.2 The static system of each aircraft shall be installed in a nominally identical manner and position. The same SSE corrections shall be incorporated in all aircraft of the group. (Threshold = Objective)

3.2.2.3 The avionics units installed on each aircraft to meet the minimum RVSM equipment requirements of paragraph 3.1 shall be manufactured to the manufacturer's same specification.

(Threshold = Objective)

Additional information. Aircraft avionics that are of a different manufacturer or part number may be considered part of the group, if it is demonstrated that this standard of equipment provides equivalent system performance.

Ref: FAA AC 91-85 Para. 9b (2) and Para. 9b(4) (Amended)

3.2.3 The Operational Envelope

The operational flight envelope is defined by aircraft limitations and performance capability, while the RVSM envelope is determined solely by altimetry system accuracy requirements over the full range of compatible gross weight ratio. For the purposes of RVSM approval, the aircraft flight envelope may be considered in two parts: the Basic RVSM Envelope and the Full RVSM Envelope. Figure 4 illustrates the Notional RVSM Basic and Full Envelopes.

3.2.3.1 The aircraft shall meet the performance requirements of the Basic RVSM Envelope.

Certification of an aircraft for RVSM will be for the Basic Envelope. The Basic RVSM Envelope is where the aircraft meets the basic accuracy requirements of subparagraphs below. (Threshold = Objective)

3.2.3.1.1 In the Basic RVSM Envelope the absolute value of the mean ASE shall not exceed 80 ft.

(Threshold = Objective)

3.2.3.1.2 In the Basic RVSM Envelope the absolute value of the mean ASE plus three standard deviations shall not exceed 200 ft. (Threshold = Objective)

Ref: FAA AC 91-85 Para. 8c (3)

3.2.3.2 The Full RVSM Envelope is where the aircraft meets the accuracy requirements of subparagraphs below. The aircraft will not be certified to the Full Envelope. The aircraft altimetry system RVSM analysis shall include the full envelope. (Threshold = Objective)

3.2.3.2.1 In the Full RVSM Envelope the absolute value of the mean ASE shall not exceed 120 ft.

(Threshold = Objective)

3.2.3.2.2 In the Full RVSM Envelope the absolute value of the mean ASE plus three standard deviations shall not exceed 245 ft. (Threshold = Objective)

Ref: FAA AC 91-85 Para. 8c(4)(Amended)

Figure 4. Notional RVSM Basic and Full Envelopes

Additional Information: This diagram is for illustrative purposes only and is not intended to reflect actual data for any aircraft. The figure above super-imposes the Basic and Full RVSM envelopes over a notional Aircraft Operating Envelope. The Basic RVSM envelope is where the aircraft operates most frequently (blue shaded region) and where less altimetry system error is permitted. When an aircraft operates near the boundaries of its operating envelope, the requirements of the Full RVSM envelope apply (red shaded region). Since the aircraft will not normally operate at the boundaries of its operating envelope, the requirements in the Full RVSM envelope are less stringent.

3.2.3.3 Non-Group Aircraft are aircraft that are not part of an approved group and a single ASE value has been established that controls the simple sum of the altimetry system errors. Each Non- Group approved aircraft shall require a flight test to quantify the ASE and establish the operating envelope, altimetry maintenance procedures, and inspection periods. Non-Group aircraft shall meet the following requirements (Threshold = Objective):

Ref: FAA AC 91-85 Para. 8c(7)

3.2.3.3.1 For all conditions in the Basic RVSM Envelope the performance shall be:

Residual Static Source Error (SSE) + worst case avionics < 160 ft. (Threshold = Objective)

3.2.3.3.2 For all conditions in the Full RVSM Envelope the performance shall be:

Residual SSE + worst case avionics < 200 ft. (Threshold = Objective)

Ref: FAA AC 91-85 Para. 8c(8)

Additional information: Worst-case avionics means that combination of tolerance values, specified by the manufacturer for the altimetry fit into the aircraft, which gives the largest combined absolute value for residual SSE plus avionics errors.

3.2.4 Static Source Error Correction (SSEC)

If the design and characteristics of the aircraft and altimetry system are such that the requirements of paragraph 3.2.2 are not satisfied by the location and geometry of the static sources alone, then the SSEC shall be applied automatically within the avionic part of the altimetry system. The design aim for static source error correction, whether aerodynamic/geometric or avionic, must lead to satisfaction of the requirements of paragraph

3.2.2 and sub-paragraphs.

Ref: FAA AC 91-85 Para. 9b(4)

3.2.5 Altitude Reporting Capability

The aircraft altimetry system shall provide an output to the aircraft transponder. (Threshold = Objective)

Ref: FAA AC 91-85 Para. 9b(5)

3.2.6 Altitude Control Output

3.2.6.1 The altimetry system shall provide an output that can be used by an automatic altitude control system to control the aircraft at a commanded altitude. The output may be used either directly or combined with other sensor signals. The output may be an altitude deviation signal, relative to the selected altitude, or a suitable absolute altitude output. (Threshold = Objective)

3.2.6.2. If SSEC is necessary in order to satisfy the requirements of paragraph 3.2.2 of this document, then an equivalent SSEC shall be applied to the altitude control output. (Threshold = Objective)

Additional information: Whatever the system architecture and SSEC system, the difference between the output to the altitude control system and the altitude displayed must be kept to the minimum.

Ref: FAA AC 91-85 Para. 9b(6)

3.2.7 Altimetry System Integrity

The predicted rate of occurrence of undetected altimetry system failures shall not exceed 1 x 10-5 per flight hour. All failures and failure combinations whose occurrence would not be evident from cross-cockpit checks, and which would lead to altitude measurement/display errors outside the specified limits, need to be assessed against this budget. No other failures or failure combinations need to be considered. (Threshold = Objective)

Ref: FAA AC 91-85 Para. 9b(7)

3.3 ALTITUDE ALERTING

The altitude deviation warning system shall signal an alert when the altitude displayed to the flight crew deviates from selected altitude by more than a nominal value. For aircraft that received Navy operational approval or FAA type certification prior to January 1, 1997, the nominal value shall not be greater than ±300 ft. For aircraft for which operational approval, type certification, or major change in type design is made after January 1, 1997, the nominal value shall not be greater than ±200

ft. The overall equipment tolerance in implementing these nominal threshold values shall not exceed ±50 ft. (Threshold = Objective)

Ref: FAA AC 91-85 Para. 9c

3.4 AUTOMATIC ALTITUDE CONTROL SYSTEM

3.4.1 As a minimum, a single automatic altitude control system shall be installed that is capable of controlling aircraft height within ±65 ft about the acquired altitude when the aircraft is operated in straight and level flight under non-turbulent, non-gust conditions. (Threshold = Objective)

Additional information: Aircraft that received Navy operational approval or FAA type certification prior to January 1, 1997, that are equipped with automatic altitude control system with flight management system/performance management system inputs which allow variations up to ±130 feet under non-turbulent, non-gust conditions do not require retrofit or design alteration.

Ref: FAA AC 91-85 Para. 9d

3.4.2 Where an altitude select/acquire function is provided, the altitude select/acquire control panel shall be configured such that an error of no more than ±25 ft exists between the display selected by the flight crew and the corresponding output to the control system.

Ref: FAA AC 91-85 Para. 9d

3.5 TRAFFIC ALERT AND COLLISION AVOIDANCE SYSTEM CAPABILITY

All aircraft equipped with TCAS II shall be equipped with a TCAS II that meets TSO C-119b (Version 7.0), or a later version, to operate in RVSM airspace.

Ref: 14 CFR, Part 91, Appendix G, Section 2, Para (g)

3.6 RVSM INSPECTION PLAN

3.6.1 Purpose

The purpose of a RVSM inspection plan is to determine that aircraft are in RVSM configuration at certification and ensure that RVSM-certified aircraft maintain compliance with RVSM configuration throughout the service life of the aircraft. These safeguards will ensure the transparency of naval aircraft operating in RVSM airspace worldwide.

3.6.2 Responsibilities for RVSM Inspection

NAVAIR PMA209 shall designate all naval aircraft as RVSM Group or Non-Group in accordance with guidance in this document. The aircraft platform PMA shall develop a RVSM inspection plan for each RVSM Group or Non-Group under their purview. The platform PMA shall incorporate the RVSM inspection plan into the appropriate aircraft publications, e.g. Naval Training and Operations Procedures (NATOPS), maintenance manuals, etc. The platform PMA is responsible for the ongoing execution of the inspection procedures in accordance with the approved plans. An aircraft shall be in compliance with the applicable Platform RVSM Inspection Plan in order to obtain and maintain approval for RVSM flight operations.

3.6.3 Requirements

The RVSM Inspection plan shall list all RVSM-critical aircraft components and shall describe the inspection procedures required to validate acceptable performance of these components.

This plan shall also specify the detailed maintenance procedures associated with these inspections, including provisions for failed inspections. The platform PMA shall incorporate this plan into the NATOPS and/or appropriate maintenance publications.

3.6.3.1 A platform RVSM Inspection plan comprises three general categories: Initial, Scheduled (calendar-driven or hourly-driven) and Unscheduled (event-driven). The inspection plan shall be developed and appropriately documented at the time of RVSM certification.

3.6.3.1.1 RVSM Initial inspections shall include a complete inventory, assessment of physical condition and ground test of the altimetry system.

3.6.3.1.2 RVSM Scheduled inspections shall be performed at regular calendar or hourly intervals, as appropriate to the aircraft RVSM Group or Non-Group and its RVSM integration.

Specific inspections shall be performed in accordance with the aircraft Maintenance Publications and are tailored to the aircraft RVSM Group or Non-Group.

3.6.3.1.3 RVSM Unscheduled Inspections shall be performed after the occurrence of events that include but are not limited to hard landings, damage, modifications to the altimetry system, or failure of an in-flight monitoring event. These events are considered “On Condition” events.

The platform PMA will define the “On Condition” events in accordance with accepted Navy practices and standards for the specific aircraft.

3.6.3.2 RVSM inspections may include but are not limited to the procedures listed below. A technical evaluation of the aircraft integration should be conducted to determine the required elements of the aircraft RVSM configuration.

3.6.3.2.1 Inventory the aircraft for installation of required RVSM components

3.6.3.2.2 A visual inspection of the normal static plates and surrounding areas

3.6.3.2.3 A Normal Static Plate Convexity/Concavity Test

3.6.3.2.4 A Static Plate Waviness Test

3.6.3.2.5 A RVSM Controlled Area Skin Inspection or Skin Waviness Test

3.6.3.2.6 A Port Height Step Check

3.6.3.2.7 An Air Data System Accuracy Test

3.6.3.2.8 A Pitot-Static Leak Test

3.6.3.2.9 An In-Flight Autopilot (altitude hold) performance verification test

3.6.3.2.10 An In-flight monitoring flight

3.6.3.2.11 A Transponder Test

3.6.3.2.12 An Altitude Alerter Test

3.6.3.2.13 A Pitot-static L-Probe alignment

3.6.3.3 RVSM inspections may include but are not limited to the components and aircraft physical systems listed below.

3.6.3.3.1 The complete aircraft altimetry system.

3.6.3.3.2 The physical condition of the aircraft skin and airframe structure in areas that could affect the airflow patterns around altimetry system sensors.

Ref: FAA AC 91-85 Para. 11[Applies to all of paragraph 3.6.3.]

3.7 RVSM MONITORING PLAN

3.7.1 PURPOSE

The purpose of the RVSM Monitoring Program is to ensure that RVSM-certified aircraft maintain compliance with RVSM performance standards throughout the service life of the aircraft. These safeguards will ensure the transparency of naval aircraft operating in RVSM airspace worldwide. A RVSM Monitoring Plan provides standard procedures for required aircraft RVSM initial and periodic monitoring.

3.7.2 RESPONSIBILITIES FOR RVSM MONITORING

NAVAIR PMA209 shall designate all naval aircraft as RVSM Group or Non-Group. The Aircraft Platform PMA shall develop and maintain a RVSM Monitoring plan for each RVSM aircraft group under their purview. The Platform PMA shall incorporate the Monitoring plans into the appropriate aircraft publications, e.g. NATOPS, maintenance manuals, etc. The Platform PMA is responsible for the ongoing execution of the Monitoring procedures in accordance with the approved plans.

3.7.3 Requirements

All U.S. Navy and Marine Corps aircraft certified for RVSM operations should conduct monitoring in accordance with Table 1. There are two types of monitoring, Initial Monitoring and Periodic Monitoring.

Ref: COMNAVAIRFORINST 13200.1, paragraph 4. (ref. k)

3.7.3.1 Initial Monitoring. The platform PMA shall complete an Initial Monitoring Phase of the aircraft or aircraft group. NAVAIR PMA209 normally certifies aircraft for RVSM after completion of Initial Monitoring.

3.7.3.1.1 A RVSM aircraft must perform Initial Monitoring to validate that the integration of RVSM capability is in accordance with the performance requirements of flight in RVSM airspace. Initial Monitoring shall be conducted on a subset of aircraft from within a designated RVSM aircraft group. For Naval Tactical aircraft, this subset shall consist of the first “x” number of aircraft modified, delivered or otherwise found compliant with the group RVSM configuration, where “x” represents a number equal to 10% of the group total. The Initial Monitoring period ends when each aircraft in the subset has successfully undergone RVSM monitoring. Newly modified/manufactured aircraft Initial Monitoring shall be completed no later than six months after the modification/delivery of the final aircraft in the subset. Aircraft groups requiring no modification shall complete Initial Monitoring within six months of designation as an RVSM aircraft group.

3.7.3.1.2 Non-Group aircraft shall monitor each individual aircraft within six months after designation as RVSM qualified. Developmental Test (DT) or Operational Test (OT) data is acceptable if collected using approved monitoring procedures.

3.7.3.1.3 Upon completion of Initial Monitoring the RVSM Group or Non-Group aircraft shall begin Periodic Monitoring as defined in paragraph 3.7.3.3 below.

3.7.3.2 Periodic Monitoring. All U.S. Navy and Marine Corps aircraft certified for RVSM operations shall conduct periodic monitoring in accordance with COMNAVAIRFORINST

13200.1 (ref. k). This instruction assigns responsibilities for periodic monitoring. The responsibilities include:

3.7.3.2.1 COMNAVAIRFOR (N42) tracks and directs the appropriate Air Wing to conduct periodic monitoring in a two year cycle per this instruction.

3.7.3.2.2 Aircraft Type/Model/Series (T/M/S) PMA will provide special instructions for conducting monitoring flights.

3.7.3.2.3 NAVAIR PMA209 will:

3.7.3.2.3.1 Determine the monitoring sample size in coordination with COMNAVAIRFOR (N42).

3.7.3.2.3.2 Notify COMNAVAIRFOR (N42) no later than 180 days prior to any monitoring deadline.

3.7.3.2.3.3 Collect and evaluate monitoring data.

3.7.3.2.3.4 Provide monitoring results to COMNAVAIRFOR (N42) and platform PMA.

3.7.3.3 RVSM periodic monitoring procedures shall be carried out in accordance with PMA209 CNS/ATM Reduced Vertical Separation Minimum (RVSM) Periodic Monitoring Policy, Revision A of 14 July 2015 (ref. j).

Table 1. Naval Tactical Group Designation and Monitoring Requirements

MONITORING

CATEGORY

INITIAL MONITORING FOR EACH

AIRCRAFT GROUP

PERIODIC

MONITORING FOR

EACH AIRCRAFT

GROUP

Initial Monitoring shall be conducted on a subset of aircraft from within a designated RVSM aircraft group. This subset shall consist of the first “x” number of aircraft modified, delivered or otherwise found compliant with the group RVSM configuration, where “x” represents a number equal to 10% of the group total.

The Initial Monitoring period ends when each aircraft in the subset has successfully undergone RVSM monitoring. Newly modified/manufactured aircraft Initial Monitoring shall be completed no later than six months after the modification/delivery of the final aircraft in the subset. Aircraft groups requiring no modification shall complete Initial Monitoring within six months of designation as an RVSM aircraft group.

Developmental Testing (DT) or Operational Testing (OT) data may be used to satisfy Initial Monitoring requirements if collected in accordance with approved monitoring procedures.

After successful completion of Initial Monitoring and Fleet Release of RVSM capability, a number equal to 10% of airframes from a designated group shall be monitored every 24 months. This 24 month period is a fixed calendar period established at fleet release of RVSM capability.

NON-

Each non-group aircraft shall be monitored within six months after designation as RVSM qualified. DT or OT data is acceptable if collected using approved monitoring procedures.

Each non-group aircraft shall be monitored every 24 months after completion of successful Initial Monitoring.

Ref: All of paragraph 3.7 except 3.7.3 (e) FAA AC 91-85 Para. 12h

APPENDIX A. ACRONYMS

AAD Assigned Altitude Deviation ADC Air Data Computer ASE Altimetry System Error ATC Air Traffic Control CNS/ATM Communication Navigation Surveillance/Air Traffic

Management CNO Chief of Naval Operations DoD Department of Defense DRVSM Domestic Reduced Vertical Separation Minimum DT Developmental Test FAA Federal Aviation Administration FAA AC Federal Aviation Administration Advisory Circular FCC Flight Control Computer FL Flight Level FRD Functional Requirements Document ICAO International Civil Aviation Organization ISA International Standard Atmosphere

in. Hg inches of Mercury JAA Joint Airworthiness Authorities MASPS Minimum Aircraft System Performance Specification NATOPS Naval Training and Operations Procedures NAVAIR Naval Air Systems Command OT Operational Test PMA Program Manager Air RGCSP Review of the General Concept of Separation Panel RVSM Reduced Vertical Separation Minimum of (300m) 1000 ft between flight levels SSE Static Source Error SSEC Static Source Error Correction SSR Secondary Surveillance Radar TC Type Certificate TCAS Traffic Collision Avoidance System TLS Target Level of Safety TVE Total Vertical Error VSM Vertical Separation Minimum

APPENDIX B. GLOSSARY

Aircraft Group. A group of aircraft that are of nominally identical design and build with respect to all details that could influence the accuracy of height keeping performance.

Altimetry System Error (ASE). The difference between the pressure altitude displayed to the flight crew when referenced to International Standard Atmosphere (ISA) standard ground pressure setting (29.92 in. Hg/1013.25 hPa) and free stream pressure altitude.

Automatic Altitude Control System. Any system which is designed to automatically control the aircraft to a referenced pressure altitude.

Barometric Altitude. Altitude as measured using barometric static pressure.

Barometric Altimetry Systems. Aircraft height measuring systems that measure altitude and display barometric altitude.

Basic RVSM Envelope. The Basic RVSM Envelope should generally encompass the full range of Long Range Cruise Mach Number plus 0.04 Mach.

Full RVSM Envelope. The Full RVSM Envelope includes parts of the flight envelope where the aircraft operates less frequently and where a larger ASE tolerance is allowed.

Functional Requirements Document (FRD). A document approved by Air Combat Electronics Program Manager (PMA209) that describes the performance an aircraft must meet in order to be certified for any one of five Communication Navigation Surveillance/Air Traffic Management functionalities. The FRD for RVSM is one such document.

General Air Traffic (GAT). Flights conducted in accordance with the rules and provisions of ICAO.

Gross Weight Ratio (W/δ). Aircraft weight, W, divided by the ratio of ambient pressure at flight altitude divided by sea level standard pressure, δ.

Height-Keeping Performance. The observed performance of an aircraft with respect to adherence to a flight level.

Monitoring. Monitoring aircraft height-keeping performance is the collection of necessary data using specialized systems, estimation of relevant performance parameters and comparison of these parameter estimates to corresponding RVSM requirements, on both an individual-aircraft and a system-wide basis. The purpose is to validate that an aircraft is in an approved RVSM configuration. Monitoring of an aircraft that is part of an approved aircraft group configuration contributes toward the minimum monitoring requirement for the affected group. Monitoring may be performed using a variety of methods which include data collection by a ground based monitoring site or an airborne system.

Non-Group Aircraft. An aircraft for which the operator applies for approval on the characteristics of the unique airframe rather than on a group basis (see paragraph 3.2.3.3.).

Operational Air Traffic (OAT). Flights which do not comply with the provisions stated for GAT and for which rules and procedures have been specified by appropriate authorities.

Periodic Monitoring. Naval Aviation will use the term “Periodic Monitoring” in lieu of the FAA term “Ongoing Monitoring”.

Residual Static Source Error. The amount by which SSE remains undercorrected or overcorrected after the application of SSEC.

RVSM Accommodation. The method by which DoD non-RVSM qualified aircraft will be cleared to fly in RVSM airspace. The FAA policy for DoD non-RVSM qualified aircraft states “The FAA will accommodate non-RVSM compliant military aircraft operation within DRVSM airspace, without mission degradation, to the extent practicable based upon existing traffic and safety considerations”. When cleared these aircraft will be provided 2,000 feet of vertical separation between FL290 and FL410.

RVSM Approval. The approval that is issued by the appropriate authority of the State in which the Operator is registered.

RVSM Inspection Program. Naval Aviation will use the term “RVSM Inspection Program” in lieu of the FAA term “Continued Airworthiness.”

Standard Deviation. The statistic that communicates the average of the deviations of the scores from the mean in a set of data.

State Aircraft. Aircraft used in military, customs and police services shall be deemed to be State Aircraft.

Static Source Error (SSE). The difference between the pressure sensed by the static system at the static port and the undisturbed ambient pressure.

Static Source Error Correction (SSEC). A correction for static source error.

Total Vertical Error (TVE). Vertical geometric difference between the actual pressure altitude flown by an aircraft and its assigned pressure altitude (flight level).

Worst Case Avionics. Avionics components which exhibit performance at or near the limit defined in paragraph 3.2.7 of this document.

APPENDIX C. ALTIMETRY SYSTEM ERROR COMPONENTS

(This section is extracted from FAA AC 91-85)

C.1. INTRODUCTION. Paragraph 10b(5)(b) states that an error budget must be established and presented in the approval data package. The requirements for this error budget are discussed in some detail in paragraph 10b(5)(c) through 10b(5)(e) for group and non-group aircraft. This appendix provides guidance to help ensure that all of the potential error sources are identified and included in the error budget for each particular model.

C.2. OBJECTIVE OF ASE BUDGET.

C.2.1 Purpose. The altimetry system error (ASE) budget demonstrates that the allocation of tolerances among the various parts of the altimetry system is, for the particular data package, consistent with the overall statistical ASE requirements. These individual tolerances within the ASE budget also form the basis of the procedures, defined in the airworthiness approval data package, which will be used to demonstrate that aircraft satisfy the Reduced Vertical Separation Minimum (RVSM) requirements.

C.2.2 Components. It is necessary to ensure that the budget takes account of all contributory components of ASE.

C.2.3 Group Approval. For group approval it is necessary to ensure either that the budget assesses the combined effect of the component errors in a way that is statistically realistic, or that the worst-case specification values are used.

C.3. ALTIMETRY SYSTEM ERROR.

C.3.1 Breakdown. Figure C.3-1, Altimetry System Error and its Components, shows the breakdown of total ASE into its main components, with each error block representing the error associated with one of the functions needed to generate a display of pressure altitude. This breakdown encompasses all altimetry system errors that can occur, although different system architectures may combine the components in slightly different ways.

C.3.1.1 The “Actual Pressure Altitude” is the pressure altitude corresponding to the undisturbed ambient pressure.

C.3.1.2 “Static Source Error” (SSE) is the difference between the undisturbed ambient pressure and the pressure within the static port at the input end of the static pressure line.

C.3.1.3 “Static Line Error” is any difference in pressure along the length of the line.

Figure C.3-1. ALTIMETRY SYSTEM ERROR AND ITS COMPONENTS

C.3.1.4 “Pressure Measurement and Conversion Error” is the error associated with the processes of transducing the pneumatic input seen by the avionics and converting the resulting pressure signal into altitude. As drawn, Figure C.3-1 represents a self-sensing altimeter system in which the pressure measurement and altitude conversion functions would not normally be separable. In an air data computer system, the two functions would be separate and SSEC would probably then be applied before pressure altitude (Hp) was calculated.

C.3.1.5 “Perfect SSEC” would be that correction which compensated exactly for the SSE actually present at any time. If such a correction could be applied, then the resulting value of Hp calculated by the system would differ from the actual altitude only by the static line error plus

Pressure at LRU port

Hp (Uncorrected)

* When using ISA standard ground pressure setting.

Actual Pressure Altitude

Altimetry System Error*

Static Source Error

Residual Static Source Error

Hp

Static Line Error (Lag and Leakage)

Perfect

SSEC

HP (With perfect SSEC)

Static Line Error Plus Pressure Measurement

& Conversion Error

Actual

SSEC

Baro-correction error

Encoding error

HpB Mode C Output

Display error

Correspondence

Pressure Measurement & Conversion

Displayed Altitude the pressure measurement and conversion error. In general, this cannot be achieved, so although the “Actual SSEC” can be expected to reduce the effect of SSE, it will do so imperfectly.

C.3.1.6 “Residual SSE” is applicable only in systems applying an avionic SSEC. It is the difference between the SSE and the correction actually applied. The corrected value of Hp will therefore differ from actual pressure altitude by the sum of static line error, pressure measurement and conversion error, and residual SSE.

C.3.1.7 Between Hp and displayed altitude occur the baro-correction error and the display error. Figure C.3-1 represents their sequence for a self-sensing altimeter system. Air data computer systems can implement baro-correction in a number of ways that would modify slightly this part of the block diagram, but the errors would still be associated with either the baro-correction function or the display function. The only exception is that those systems that can be switched to operate the display directly from the Hp signal can eliminate baro-correction error where standard ground pressure setting is used, as in RVSM operations.

C.3.2 Components. The altimetry system errors presented in Table C.3-1 and described in paragraph 3.2.2 are discussed below in greater detail.

C.