Page7.313Route Operations
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IPH Chapter Three
 EN ROUTE OPERATIONS…EN ROUTE NAVIGATION; …AIR ROUTE TRAFFIC CONTROL CENTERS; …PREFERRED IFR ROUTES; …SUBSTITUTE EN ROUTE FLIGHT PROCEDURES; …TOWER EN ROUTE CONTROL; …AIRWAY AND ROUTE SYSTEM; …MONITORING OF NAVIGATION FACILITIES; …LOW FREQUENCY AIRWAYS/ROUTES; …VHF AIRWAYS/ROUTES; … VHF EN ROUTE OBSTACLE CLEARANCE AREAS; …PRIMARY AREA; …SECONDARY AREA; …NAVAID SERVICE VOLUME; …NAVIGATIONAL GAPS; …CHANGEOVER POINTS; …IFR EN ROUTE ALTITUDES; …MINIMUM EN ROUTE ALTITUDE; …MINIMUM OBSTRUCTION CLEARANCE ALTITUDE; …MINIMUM VECTORING ALTITUDES; …MINIMUM RECEPTION ALTITUDE; …MINIMUM CROSSING ALTITUDE; …MAXIMUM AUTHORIZED ALTITUDE; …IFR CRUISING ALTITUDE OR FLIGHT LEVEL; …LOWEST USABLE FLIGHT LEVEL; …RADAR CONTACT REPORTING PROCEDURES; …POSITION REPORT ITEMS; …NON-RADAR POSITION REPORTS; …COMMUNICATION FAILURE; …CLIMBING AND DESCENDING EN ROUTE; …PILOT/CONTROLLER EXPECTATIONS; …AIRCRAFT SPEED AND ALTITUDE; …HOLDING PROCEDURES; …ATC HOLDING INSTRUCTIONS; …MAXIMUM HOLDING SPEED; …HIGH PERFORMANCE HOLDING; …FUEL STATE AWARENESS; …DIVERSION PROCEDURES; …EN ROUTE RNAV PROCEDURES; …OFF AIRWAY ROUTES; …DIRECT FLIGHTS; …RANDOM RNAV ROUTES; …OFF ROUTE OBSTACLE CLEARANCE ALTITUDE; …PUBLISHED RNAV ROUTES; …COMPOSITION OF DESIGNATORS; …USE OF DESIGNATORS IN COMMUNICATIONS; …RNAV MINIMUM EN ROUTE ALTITUDE; …MINIMUM IFR ALTITUDE; …WAYPOINTS; …USER-DEFINED WAYPOINTS; …FLOATING WAYPOINTS; …COMPUTER NAVIGATION FIXES; …NATIONAL ROUTE PROGRAM; …ADVANCED AREA NAVIGATION ROUTES;  ...IFR TRANSITION ROUTES; …REQUIRED NAVIGATION PERFORMANCE; …REDUCED VERTICAL SEPARATION MINIMUMS; …

 EN ROUTE OPERATIONS
---Flight standards are set by Title 14 of the Code of Federal Regulations (CFR)
---En route is segment from termination point of departure procedure to origination point of arrival procedure

EN ROUTE NAVIGATION
---National Airspace System (NAS) consists of lowest from base of controlled airspace to 18,000 MSL
---Second stratum extends from 18,000 MSL to Flight Level (FL) 450
---Third stratum extends from FL 450 and above is for random, point-to-point navigation
---Under IFR pilots must fly the center of airways or direct between navaids or fixes defining a route
---All restrictions allow traffic avoidance as necessary

AIR ROUTE TRAFFIC CONTROL CENTERS (ARTCC)
---Twenty ARTCCs have 20 to 80 sectors defined by traffic, airways and workload
---The Code of Federal Regulations (CFRs) require pilots to monitor appropriate frequencies
---National Aeronautical Charting Office (NACO) makes charts with Centers, Sectors and frequencies
---Flights are handed-off as passage requires to new frequency and sector.
---Controller gives the pilot the name of the agency, frequency required for handoff
---Pilot makes contact by naming the agency, aircraft call-sign, and altitude situation
---Charted frequencies can be used for ‘Pop-up’ flight plan filing
---En route pilots are responsible for obstacle, traffic avoidance and situational awareness

PREFERRED IFR ROUTES
---Use of preferred routes as designed by ATC moves traffic ‘better’ by avoiding high traffic areas
---Preferred routes seem designed for highest traffic situations to divert all neighboring traffic
---Present ARTCC system can predict congestion and choke points and hold traffic on the ground
---Preferred IFR routes are published in the A/FD
---Some preferred routes begin at a fix that you will get to by way of a vector
---The FAA computer will give you a preferred route whether you want it or not. so take it and change later
Notes:
---There are no preferred routes that take a flight even close to the San Francisco Class Bravo airspace
---Once into the preferred routing you should seek any ‘corner cutting’ options on each handoff
---One way around areas such as the Los Angeles Basin is to file inside and amend out an edge route later
---I once filed an 80 mile direct flight through the basin that took 215 miles of routes and vectors.

SUBSTITUTE EN ROUTE FLIGHT PROCEDURES
---ARTCCs establish substitute airways and route segments when facilities are shutdown or fail.
---Scheduled shutdown of facilities is anticipated by NOTAM otherwise as required
---Substitute airways must be in controlled airspace and be flight inspected by FAA
---Minimum en route and maximum en route with temporary reporting points are provided and tested
---A minimum reception altitude (MRA) is determined for each temporary reporting point.

TOWER EN ROUTE CONTROL (TEC)
---If you can fly without using ARTCC you can file an IFR tower en route between city pairs far apart
---When on a TEC flight plan you remain in approach control airspace
---All tower en route city pairs are listed in the A/FD with direct routing between navaid facilities
---Coded identifiers for the route can be used instead of filing the route

AIRWAY AND ROUTE SYSTEM
---The present en route system is based on VHF airway/route navigation system

MONITORING OF NAVIGATION FACILITIES
---AFSS and ARTCC sectors determine the operational status of navigation facilities based on internal tests
---Prior to any flight, a pilot should check notices to airmen (NOTAMS) regarding performance of navaids

LOW FREQUENCY AIRWAYS/ROUTES (LF)
---In Alaska only
---Range does not have the line-of-sight limitation of VHF frequencies

VHF AIRWAYS/ROUTES
---May have Maximum Authorized Altitudes because of radio limitations
---The Change Over Point (COP) between VHF navaids is midway unless otherwise charted

VHF EN ROUTE OBSTACLE CLEARANCE AREAS
---Obstacle clearance areas for the en route flight are identified as primary, secondary and turning areas
---Navigation airway is 4.5 or 6.7 NM to each side based upon factors of accuracy and probability
---The accuracy is 4.5 degrees out to 51 miles 95% of the time meaning 5% of the time you exceed 4nm
---The accuracy is 6.7 degrees out to 51 miles 99% of the time when airway is 12 miles wide.

PRIMARY AREA
---The primary obstacle clearance area of an airway is 4 NM to each side of center 1000’ above obstacles
---Differences is clearance areas exist where a dogleg occurs or Change Over Points (COP) are unequal
--- In mountainous areas (actually hilly) the obstacle clearance area is 2000’ above obstacles
---In some locations the 2000’ may be reduced to 1700’ or even 1500’
---Precipitous terrain
---Weather phenomena
---Pressure differentials
---Type and distance between navaids
---Weather services
---Altimeter setting accuracy
---1000’ over manmade obstacles if not subject to low pressure Bernoulli Effect

SECONDARY AREA
---Extends 2NM beyond 8NM primary area to each side giving total of 6NM each side of center line
---The secondary obstacle clearance plane begins at a point 500’ above the obstacle basis for the primary area and angles out for two miles and up another 500 feet. Draw it to see it.
---Pilots are expected to lead turns before a fix (Figure 3-13)

NAVAID SERVICE VOLUME
---The use of the term volume is a GovSpeak misleading and potentially dangerous way of saying how far a radio signal may be used. They think of radio signals as being in a cylinder. Do you?
---Maximum distances vary with altitude and obstacles obstructing line of sight signals
---12000 and below (terminal facilities) 50NM
---Below 18000 80NM
---14500 to 17999 200NM
---18000 to FL 450 260NM
---Above FL450 200NM
---If cleared to a facility beyond your range by ATC they will monitor your flight with radar

---Exist called MEA gap can still be approved for a distance related to altitude with one gap per airway
---MEA steps are limited to one step between facilities
---A navigational gap is not identified on the chart by distances from navaids

CHANGE OVER POINTS (COP)
---Normal COP is midway between navaids unless otherwise depicted on chart with numerical legs
---The COP assures navaid reception at IFR minimum altitude
---The COP affects the primary and secondary obstacle clearance areas
---Offset COP and dogleg segments of airways result in a flare in the width at the COP

IFR EN ROUTE ALTITUDES
---Altitudes selected for adequate signal to keep flight within route widths
---IFR FARs requires that pilots fly at or above IFR minimum altitudes on IFR flights
---Mountainous areas require IFR flight 2000’ above the obstacle within 4NM of airway centerline
---Non-mountainous areas minimum IFR altitude is1000’ above any obstacle within 4NM centerline
---Exception: Within 22NM of VOR pilot can fly down to Minimum Obstacle Clearance Altitude (MOCA)
---Climbing to higher Minimum IFR Altitude (MIA) must begin at the first point that is higher.
---When obstruction exists begin climb so as to get vertical separation from terrain
---The Minimum Crossing Altitude (MCA) applies to the VOR point as published
---On an IFR flight and cleared to VFR on top flight at or above minimum IFR altitudes must be maintained
---Minimum IFR altitudes apply to all IFR flights regardless of weather conditions

MINIMUM EN ROUTE ALTITUDE (MEA)
---MEA is the lowest altitude between radio fixes giving acceptable signal and obstacle clearance
---MEAs are buffered 300’ above transition area altitudes and 500’ within control areas
---MEAs provide obstacle clearance, navigation signal and communication but...
---Communications at MEA is not guaranteed

MINIMUM OBSTRUCTION CLEARANCE ALTITUDE (MOCA)
---The lowest published altitude gives obstacle clearance for entire route segment
---Assures navigational signal within 22NM of facility
---MOCA set to Required Obstacle Clearance (ROC) is computed by TERPS to nearest 100’
---1000’ additional is added in mountainous areas
---ATC will warn pilots if aircraft by giving a safety alert and pilot should advise as to action taken

MINIMUM VECTORING ALTITUDES (MVAs)
---Some MVAs have lower altitudes than MOCAS and MEAs but most are same as MOCAs and MEAs
---MVA charts are available to ATC but not to pilots

MINIMUM RECEPTION ALTITUDE (MRA)
---These are FAA flight tested altitudes on every route.
---Should the fix MRA be above the MEA a new MRA for the fix is required to use the fix

MINIMUM CROSSING ALTITUDE (MCA)
---MCA is lowest altitude to be at when proceeding toward a higher minimum en route IFR altitude
---MCAs are used preceding a higher en route altitude (Figure 3-18) having obstacles
---When a change of altitude is combined with a route change course guidance may be required
---MCA climb Gradients:
---Sea level through 5000’MSL –150’ per NM
---5000 through 10000’MSL 120’ per NM
---10000 through and over 100’ per NM

MAXIMUM AUTHORIZED ALTITUDE (MAA)
---Procedural limits determined by technical limits of airspace or frequency interference

IFR CRUISING ALTITUDE or FLIGHT LEVEL
---When in IFR flight pilots must maintain altitudes and headings as assigned by ATC
---For IFR cruising altitudes see Figure 3-21 all courses are magnetic
---When below 18,000 MSL altimeter setting must be set by (closest) source within 100 NM
---Any change in altitude must be (requested/reported) to ATC

LOWEST USABLE FLIGHT LEVEL
---The true altitude of an aircraft is lower than indicated when barometric pressure is lower than standard
---When flying below 18000 feet in NOTAMED low pressure conditions set altimeter to 31.00

RADAR CONTACT REPORTING PROCEDURES (Figure 3-23)
---Always acknowledge and read back a handoff from one controller to another
---Leaving one altitude for another while always using the words climbing and descending
---Any VFR-on-top change in altitude
---Leaving any assigned holding fix or point
---Missed Approach
---Unable to climb/descend at 500 fpm
---True Air Speed (TAS) variation of 5% or 10 knots from filed speed
---Time (after the hour) and altitude on reaching holding fix or clearance limit
---Loss of nav/comm capability
---Un-forecast weather or safety change

POSITION REPORT ITEMS (FIGURE 3-24)
---Identification, position, time, altitude, IFR/VFR, ETA of next fix, name of next fix and remarks

NON-RADAR POSITION REPORTS
---Leaving FAF or OM when inbound
---ETA over three minutes off
---Position reporting as required (over facilities and solid triangles)
---Off airways with filed fixes, report all fixes used in flight plan
---Mandatory reporting points apply to VFR-on-top giving position, route, and ETA.
---Time may be given in minutes if no misinterpretation is possible

COMMUNICATION FAILURE
---See AIM for all requirements
---Should your comm radios fail ATC may try to contact you on VOR frequencies or previous frequency
---Regulations try to get you out of IFR flight plan get to VFR when able if unable comply with regulations
---On radio failure aircraft is expected to squawk 7600 this shows as a flashing RDOF on the radar screen
Route
---Fly the route assigned in last clearance
---If being vectored fly direct to fix, route or airway specified in radar clearance
---In no assigned or expected route fly route as filed
Altitude
---As assigned in last clearance
---Fly minimum IFR altitude
---Fly altitude advised to expect
---Climb to MEA and MCAs as they occur

CLIMBING AND DESCENDING EN ROUTE
---Position reports only if radar fails
---En route flight includes climbing, level, and descending on ARTCC flight progress strip
---Flight has communications, reports, response to clearances, monitoring position and equipment status

PILOT/CONTROLLER EXPECTATIONS
---ATC clearances or instructions require pilot execution on receipt

---‘immediately’ said by ATC is a sign of urgency in required response
---"Climb at pilot’s discretion" allows pilot to select rate, level off any time but cannot go down again
---If no ATC climb restrictions are made pilot climbs at optimum rate until 1000’ below assigned altitude
---Advise ATC if at any time you are unable to climb at 500 feet per minute
---"expedite climb" means to climb at maximum rate but ‘expedite’ is cancelled by any new requirement.
---All clearances given and clearance readbacks require accuracy or clarification

AIRCRAFT SPEED AND ALTITUDE
---ATC anticipates the 10,000’ 250-knot airspeed limit and expects you to anticipate as well.
---Pilots are expected to maintain assigned speed + ten knots
---ATC radar can issue speed adjustments according to traffic needs. I was once told to slow my C-172
---Never hesitate to query ATC if you even THINK there is a clearance or instruction discrepancy
---‘Expect" clearances are for planning purposes only not to be read back until issued as a flight clearance

HOLDING PROCEDURES
---Criteria for the holding pattern are what it takes for separation and obstacle clearance purposes
---The hold is 1000’ above any obstacle in the primary area and 500’ above obstacles in the secondary area
---When ATC tells you to climb in a hold, no obstacle can be at any of the hold altitudes
---Holding factors are facility errors, wind, procedures, ATC control, outbound leg, airspeed, DME error, airspace size and altitude. Order 7130.3 Holding Pattern Criteria sets the limits

ATC HOLDING INSTRUCTIONS
---Holding instructions are at least five minutes before ETA to the fix
---Pilots are expected to hold at a published fix as published
---Given are direction to fix, fix name, course and leg length turn direction understood or specified, EFC
---You should fly right turns unless left turns are specified.
---Loss of radio requires you to leave the fix at the EFC time
---At the clearance limit without a new clearance, query ATC, hold at the fix on inbound course right turns
---ATC may hold you at designated reporting point at the higher of MEA or MRA
---Unplanned holds at fixes on airway or route radials, bearings or courses
Clearance for Charted Holding Patterns
----Direction to hold from the fix
---Name of the fix
---Expect Further Clearance (EFC) time
Clearance for Uncharted Holding Patterns
---Direction hold from the fix
---Name of fix
---Holding course by radial, bearing, airway or route
---Outbound leg length by time or miles
---Nonstandard pattern
---EFC time

MAXIMUM HOLDING SPEED
---Altitude ranges have speed limits to keep plane in bounds you are to slow down accordingly
200 knots ias ---Minimum Holding Altitude (MHA) up to 6000 feet
230 knots ias ---6000 feet up to 14000 feet
265 knots IAS ---14000 feet up

HIGH PERFORMANCE HOLDING
Military allowed 310 knots IAS

FUEL STATE AWARENESS
---Commercial aircraft required to track time and fuel remaining during flight
---Top of Climb (TOC) is the altitude maintained at level cruise
---Pilot Not Flying (PNF) tracks fuel burn and tells results to pilot flying (PF)

DIVERSION PROCEDURES
---Aircraft must be able to land
---Passengers and crew must be able to disembark
---All physiological needs supplied until safe evacuation
---Total recovery of all within 12 to 48 hours
---Designation of alternate airport in IFR flight plan is first step

EN ROUTE RNAV PROCEDURES
---RNAV is any system that has facilities that allow flight on any course within its ‘volume’
---Required navigational performance (RNP) concept with improved technology gives us RNAV
NEW RNAV PROCEDURES FOR INSTRUMENT PILOTS 1-9-05
On September 1, the FAA implemented new RNAV procedures in both terminal and high-altitude airspace. If you're an IFR pilot and you file as a "/G," you should be prepared to fly RNAV instrument departure procedures (SIDs on Jeppesen charts, DPs in NACO publications) and standard terminal arrival routes (STARs). And you now have access to new RNAV "T" routes to ease your way through some Class B airspace and "Q" routes to shorten the distance if you're flying above 18,000 feet. If you have an IFR-approved panel-mount GPS, you probably have the equipment you need. "The FAA is turning more and more to satellite navigation, which is something that AOPA has encouraged for a long time," said Randy Kenagy, AOPA director of advanced technology. "RNAV means more direct routes, more efficient use of airspace, and time and money savings for pilots." For more on what you need to know to fly RNAV procedures, see AOPA Online ( http://www.aopa.org/whatsnew/newsitems/2005/050901rnav.html ).

OFF AIRWAY ROUTES
---Off airway routes are established using the same criteria, as are the airway routes
---Off airways routes are within controlled airspace using existing facilities
---Off airways avoid military bases, training areas and military operations areas
---Off airways operations requirements include reduced vertical separation, long range radio over water, special fuel reserves, extended range, areas of magnetic unreliability, multiple long range navigation

DIRECT FLIGHTS
---A straight line on a Lambert Conformal Conic Projection is very close to a geodesic line
---The closer the line is parallels of 33 degrees and 45 degrees the better flight’s straight line
---North and south directions have practically no distortion
---Direct flights off airways are still dependent on service volume distance limitations

RANDOM RNAV ROUTES
---Random RNAV routes are direct routes based on RNAV
---All Random RNAV routes require radar but be aware of range (volume) of facilities used
---All ARTCCs have unpublished Minimum Instrument Altitudes (MIA) available by asking

OFF ROUTE OBSTACLE CLEARANCE ALTITUDE (OROCA)
---OROCA is same as on airways 2000’ four miles laterally in mountains otherwise 1000’ above
---When on a clearance below minimums you are responsible until reaching MEA, MIA, MVA or OROCA
---Advise ATC and state intentions if you are unable to reach or maintain OROCA minimums
---All direct routes should be planned to avoid prohibited or restricted airspace by 3 NM
---All random RNAV flights must have one waypoint in each ARTCC area flown
---Turning points on an off route must be part of the flight plan filed

PUBLISHED RNAV ROUTES
---En route charts are required when on an RNAV flight
---Published routes are fixed, permanent and charted for flight planning for RNAV flight

COMPOSITION OF DESIGNATORS

---Basic route RNAV designator consists of one or two letters followed by a number from l1 to 999
---RNAV route may overlay existing routes but using a different code on the charts Last letter will be R

USE OF DESIGNATORS IN COMMUNICATIONS
Phonic changes referenced to RNAV
---Letter K = "Kopter" obviously a helicopter route
---Letter U = "Upper" obviously upper altitudes
---Letter S = "Supersonic"
See Page 3-32

RNAV MINIMUM EN ROUTE ALTITUDE
---RNAV MEA are given on IFR en route charts when they exist

MINIMUM IFR ALTITUDE (MIA)
---If not prescribed standard is 2000’ above obstacle when mountainous, otherwise 1000’ above
---MIAs are not flight checked for communications

WAYPOINTS
---Geographical points used to define RNAV route or flight path
---Waypoints may be predefined, published, floating or user-defined
---Predefined published waypoints are defined relative to VOR, DME, or VORTAC
---All waypoints are given five-letter pronounceable names

USER-DEFINED WAYPOINTS
---Pilot created for use in random RNAV direct navigation
---Will be given to ATC by bearing and distance or longitude and latitude
---Offset phantom waypoints (remain to be defined in the book—glossary same as text)

FLOATING WAYPOINTS
---Not associated with existing airways but may be used as traffic metering fixes, holding point, STAR origination points and SID termination points (Figure 3-3
---Any one waypoint entered incorrectly into your flight data plan will derail your flight

COMPUTER NAVIGATION FIXES
---Database waypoint identifiers are on charts enclosed in parentheses
--- Identifiers are also Computer Navigation Fixes (CNFs) not used by ATC, nor in flight plans, or radio
---Database identifiers are to be used for orientation, navigation and situational awareness
---Computers are NOT to be used as a substitute for paper charts (will the FAA ever give up pencils?)
---The pilot should know the RNAV system he is using but more importantly are its limitations

NATIONAL ROUTE PROGRAM (NRP)
---The National Route Program is a set of rules and procedures for ‘free flight’ in the system
---Choice for efficient, economical flight above FL29
---Simple clearances with flight planning and lost communications protection
---Two airspace zones around aircraft protected and alert internal warning when alert meets alert
---Made possible by Automatic dependent surveillance broadcast (ADS-B) GPS system not ATC
---Aircraft broadcasts its position to be displayed to every other aircraft more accurate than radar
---ADS-B works at all altitudes and on the ground
---User Request Evaluation Tool (URET) gives enhanced, automated flight data management
---URET predicts aircraft conflicts of five miles as RED and twelve miles as YELLOW
---A BLUE alert warns of aircraft and airspace conflict
---As of 1-1-05 six of the ARTCC centers of the 24 existing have URET

ADVANCED AREA NAVIGATION ROUTES (ANR)
---Properly equipped aircraft in western and Pacific areas

IFR TRANSITION ROUTES
---Working to provide over flight of Class B airspace for RNAV codes E, F, G capable IFR aircraft
---Effort being made to let limited performance General Aviation aircraft to use these routes

REQUIRED NAVIGATION PERFORMANCE
---Taking the place of NDB, VOR and LORAN will be Flight Management System and GPS are
---Required Navigation Performance (RNP) and Reduced Vertical Separation Minimums (RVSM)
---Minimum Navigation Performance Specifications (MNPS) and Gross Navigation Error (GNE)
---Atlantic Ocean errors of 25 miles or 300 feet disrupt the safety factors applying even to Part 91
---Required Navigational Performance of 0.1 is about 608 feet. That’s about a city block.
---RPN procedures requires new pilot communications, limitations, and terminology
---RPN airspace is generic term for routes, legs, operations and procedures
---Estimated Position Error (EPE) same as Actual Navigation Performance (ANP)
---See Figure 3-45

REDUCED VERTICAL SEPARATION MINIMUMS (RVSM)
---RVSM airspace is between FL 290 and FL 41) with 1000 foot vertical separation effective 2005
---(History of vertical separation) Latest in February 2005 1000' between FL290 and FL410

END of Chapter 3: Route Operations
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