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Archive / FAA Instrument Procedures Handbook / FAA Instrument Procedures Handbook: Chapter 2 — En Route Operations

Chapter 2 — En Route Operations — Part 7

Chapter 2 — En Route Operations — Part 7

FAA-H-8083-16B (2017)

En Route Reporting Procedures

In addition to acknowledging a handoff to another Center

en route controller, there are reports that should be made

without a specific request from ATC. Certain reports should

be made at all times regardless of whether a flight is in radar

contact with ATC, while others are necessary only if radar

contact has been lost or terminated. [Figure 2-68]

Non-Radar Position Reports

If radar contact has been lost or radar service terminated,

the CFRs require pilots to provide ATC with position reports

over designated VORs and intersections along their route

of flight. These compulsory reporting points are depicted

on IFR en route charts by solid triangles. Position reports

over fixes indicated by open triangles are noncompulsory

reporting points and are only necessary when requested by

ATC. If on a direct course that is not on an established airway,

report over the fixes used in the flight plan that define

the route, since they automatically become compulsory

reporting points. Compulsory reporting points also apply

when conducting an IFR flight in accordance with a VFR-

on-top clearance.

Whether a route is on an airway or direct, position reports

are mandatory in a non-radar environment, and they

must include specific information. A typical position

report includes information pertaining to aircraft position,

expected route, and ETA. When a position report is to be

made passing a VOR radio facility, the time reported should

be the time at which the first complete reversal of the TO/

FROM indicator is accomplished. When a position report is

made passing a facility by means of an airborne ADF, the

time reported should be the time at which the indicator

makes a complete reversal. When an aural or a light panel

indication is used to determine the time passing a reporting

point, such as a fan marker, Z marker, cone of silence or

intersection of range courses, the time should be noted

when the signal is first received and again when it ceases.

The mean of these two times should then be taken as the

actual time over the fix. If a position is given with respect to

distance and direction from a reporting point, the distance

and direction should be computed as accurately as possible.

Except for terminal area transition purposes, position

reports or navigation with reference to aids not established

for use in the structure in which flight is being conducted

are not normally required by ATC.

Flights in a Radar Environment

When informed by ATC that their aircraft are in “Radar

Contact, ” pilots should discontinue position reports over

designated reporting points. They should resume normal

position reporting when ATC advises “radar contact lost”

or “radar service terminated. ” ATC informs pilots that they

are in radar contact:

1. When their aircraft is initially identified in the

ATC system; and

2. When radar identification is reestablished after

radar service has been terminated or radar

contact lost.

Subsequent to being advised that the controller has

established radar contact, this fact is not repeated to

the pilot when handed off to another controller. At

times, the aircraft identity is confirmed by the receiving

controller; however, this should not be construed to

mean that radar contact has been lost. The identity of

transponder equipped aircraft is confirmed by asking

the pilot to “ident, ” “squawk standby, ” or to change

codes. Aircraft without transponders are advised of

their position to confirm identity. In this case, the pilot

is expected to advise the controller if in disagreement

with the position given. Any pilot who cannot confirm

the accuracy of the position given because of not being

tuned to the NAVAID referenced by the controller

should ask for another radar position relative to the

tuned in NAVAID.

Position Report Items

Position reports should include the following items:

1. Aircraft identification

2. Position

3. Time

4. Altitude or flight level (include actual altitude

or flight level when operating on a clearance

specifying VFR-on-top)

5. Type of flight plan (not required in IFR position

reports made directly to ARTCCs or approach

control)

6. ETA and name of next reporting point

7. The name only of the next succeeding reporting

point along the route of flight

8. Pertinent remarks

Additional Reports

The following reports should be made at all times to

ATC or Flight Service facilities without a specific ATC

request:

1. When vacating any previously assigned altitude

or flight level for a newly assigned altitude or

flight level.

2. When an altitude change is made if operating

on a clearance specifying VFR-on-top.

3. When unable to climb/descend at a rate of a least

500 feet per minute (fpm).

4. When approach has been missed. (Request clearance

for specific action (i.e., to alternative airport, another

approach).

5. Change in the average true airspeed (at cruising

altitude) when it varies by 5 percent or 10 knots

(whichever is greater) from that filed in the flight

plan.

6. The time and altitude or flight level upon reaching

a holding fix or point to which cleared.

7. When leaving any assigned holding fix or point.

Note: The reports stated in subparagraphs 6 and

7 may be omitted by pilots of aircraft involved in

instrument training at military terminal area facilities

when radar service is being provided.

8. Any loss, in controlled airspace, of VOR, TACAN,

ADF, low frequency navigation receiver capability,

GPS anomalies while using installed IFR-certified

GPS/GNSS receivers, complete or partial loss of ILS

receiver capability or impairment of air/ground

communications capability. Reports should include

aircraft identification, equipment affected, degree

to which the capability to operate under IFR in the

ATC system is impaired, and the nature and extent

of assistance desired from ATC.

9. Any information relating to the safety of flight.

Other equipment installed in an aircraft may impair your

ability to safely operate under IFR. If a malfunction of

such equipment (e.g., weather radar) affects any safety or

IFR capability, reports should be made as stated above.

When reporting GPS anomalies, be very specific and

include the location, altitude, and duration of the anomaly.

Deliberate GPS interference or outage areas resulting from

pre-approved government tests will be disseminated in

NOTAMs. These outages should not be reported to ATC,

as this condition is known and not an anomaly. See also

AIM 1-1-13.

Communication Failure

Two-way radio communication failure procedures for IFR

operations are outlined in 14 CFR Part 91, § 91.185. Unless

otherwise authorized by ATC, pilots operating under IFR

are expected to comply with this regulation. Expanded

procedures for communication failures are found in the

Aeronautical Information Manual (AIM). Pilots can use the

transponder to alert ATC to a radio communication failure by

squawking code 7600. [Figure 2-69] If only the transmitter

is inoperative, listen for ATC instructions on any operational

receiver, including the navigation receivers. It is possible ATC

may try to make contact with pilots over a VOR, VORTAC,

NDB, or localizer frequency. In addition to monitoring

NAVAID receivers, attempt to reestablish communications

by contacting ATC on a previously assigned frequency or

calling an FSS.

The primary objective of the regulations governing

communication failures is to preclude extended IFR

no-radio operations within the ATC system since these

operations may adversely affect other users of the airspace.

If the radio fails while operating on an IFR clearance, but

in VFR conditions, or if encountering VFR conditions at

any time after the failure, continue the flight under VFR

conditions, if possible, and land as soon as practicable. The

requirement to land as soon as practicable should not be

construed to mean as soon as possible. Pilots retain the

prerogative of exercising their best judgment and are not

required to land at an unauthorized airport, at an airport

unsuitable for the type of aircraft flown, or to land only

When an aircraft squawks code 7600 during a two-way radio

communication failure, the information block on the radar

screen flashes RDOF (radio failure) to alert the controller.

Figure 2-69. Two-way radio communications failure transponder code.

minutes short of their intended destination. However, if

IFR conditions prevail, pilots must comply with procedures

designated in the CFRs to ensure aircraft separation.

If pilots must continue their flight under IFR after

experiencing two-way radio communication failure, they

should fly one of the following routes:

• The route assigned by ATC in the last clearance

received.

• If being radar vectored, the direct route from the

point of radio failure to the fix, route, or airway

specified in the radar vector clearance.

• In the absence of an assigned route, the route ATC

has advised to expect in a further clearance.

• In the absence of an assigned or expected route, the

route filed in the flight plan.

It is also important to fly a specific altitude should two-way

radio communications be lost. The altitude to fly after a

communication failure can be found in 14 CFR Part 91, §

91.185 and must be the highest of the following altitudes

for each route segment flown.

• The altitude or flight level assigned in the last ATC

clearance.

• The minimum altitude or flight level for IFR

operations.

• The altitude or flight level ATC has advised to expect

in a further clearance.

In some cases, the assigned or expected altitude may not be as

high as the MEA on the next route segment. In this situation,

pilots normally begin a climb to the higher MEA when they

reach the fix where the MEA rises. If the fix also has a published

MCA, they start the climb so they are at or above the MCA

when reaching the fix. If the next succeeding route segment

has a lower MEA, descend to the applicable altitude either

the last assigned altitude or the altitude expected in a further

clearance—when reaching the fix where the MEA decreases.

ARTCC Radio Frequency Outage

ARTCCs normally have at least one back-up radio receiver

and transmitter system for each frequency that can usually

be placed into service quickly with little or no disruption of

ATC service. Occasionally, technical problems may cause a

delay but switchover seldom takes more than 60 seconds.

When it appears that the outage is not quickly remedied,

the ARTCC usually requests a nearby aircraft, if there is

one, to switch to the affected frequency to broadcast

communications instructions. It is important that the pilot

wait at least one minute before deciding that the ARTCC has

actually experienced a radio frequency failure. When such

an outage does occur, the pilot should, if workload and

equipment capability permit, maintain a listening watch

on the affected frequency while attempting to comply with

the following recommended communications procedures:

1. If two-way communications cannot be established

with the ARTCC after changing frequencies, a pilot

should attempt to re-contact the transferring

controller for the assignment of an alternative

frequency or other instructions.

2. When an ARTCC radio frequency failure occurs after

two-way communications have been established,

the pilot should attempt to reestablish contact with

the center on any other known ARTCC frequency,

preferably that of the next responsible sector when

practicable, and ask for instructions. However,

when the next normal frequency change along

the route is known to involve another ATC facility,

the pilot should contact that facility, if feasible,

for instructions. If communications cannot be

reestablished by either method, the pilot is expected

to request communication instructions from the FSS

appropriate to the route of flight.

Note: The exchange of information between an aircraft

and an ARTCC through an FSS is quicker than relay via

company radio because the FSS has direct interphone

lines to the responsible ARTCC sector. Accordingly,

when circumstances dictate a choice between the two

during an ARTCC frequency outage relay via FSS radio is

recommended.

Climbing and Descending En Route

When ATC issues a clearance or instruction, pilots are

expected to execute its provisions upon receipt. In some

cases, ATC includes words that modify their expectation.

For example, the word “immediately” in a clearance or

instruction is used to impress urgency to avoid an imminent

situation, and expeditious compliance is expected and

necessary for safety. The addition of a climb point or time

restriction, for example, does not authorize pilots to deviate

from the route of flight or any other provision of the ATC

clearance. If the pilot receives the term “climb at pilot’s

discretion” in the altitude information of an ATC clearance,

it means that the pilot has the option to start a climb when

they desire and are authorized to climb at any rate, and to

temporarily level off at any intermediate altitude as desired,

although once you vacate an altitude, you may not return to

that altitude. When ATC has not used the term nor imposed

any climb restrictions, pilots should climb promptly on

acknowledgment of the clearance. Climb at an optimum

rate consistent with the operating characteristics of the

aircraft to 1,000 feet below the assigned altitude, and then

attempt to climb at a rate of between 500 and 1,500 fpm

until the assigned altitude is reached. If at any time the

pilot is unable to climb at a rate of at least 500 fpm, advise

ATC. If it is necessary to level off at an intermediate altitude

during climb, advise ATC.

When ATC issues the instruction, “Expedite climb, ” this

normally indicates that the pilot should use the approximate

best rate of climb without an exceptional change in aircraft

handling characteristics. Normally controllers inform pilots

of the reason for an instruction to expedite. If flying a

turbojet aircraft equipped with afterburner engines, such as

a military aircraft, pilots should advise ATC prior to takeoff

if intending to use afterburning during the climb to the en

route altitude. Often, the controller may be able to plan

traffic to accommodate a high performance climb and allow

the pilot to climb to the planned altitude without “expedite”

clearance from restriction. If you receive an ATC instruction,

and your altitude to maintain is subsequently changed

or restated without an expedite instruction, the expedite

instruction is canceled.

During en route climb, as in any other phase of flight,

it is essential that you clearly communicate with ATC

regarding clearances. In the following example, a flight crew

experienced an apparent clearance readback/hearback

error, that resulted in confusion about the clearance and,

ultimately, to inadequate separation from another aircraft.

“Departing IFR, clearance was to maintain 5,000 feet,

expect 12,000 in 10 minutes. ” After handoff to Center, the

pilot understood and read back, “Leaving 5,000 turn left

heading 240° for vector on course. ” The pilot turned to the

assigned heading climbing through 5,000 feet. At 5,300 feet,

Center advised assigned altitude was 5,000 feet. The pilot

immediately descended to 5,000. Center then informed

the pilot that there was traffic at 12 o’clock and a mile at

6,000. After passing traffic, a higher altitude was assigned

and climb resumed. The pilot then believed the clearance

was probably "reaching" 5,000, etc. Even the readback to the

controller with "leaving" did not catch the different wording.

“Reaching” and “leaving” are commonly used ATC terms

having different usages. They may be used in clearances

involving climbs, descents, turns, or speed changes. In the

flight deck, the words “reaching” and “leaving” sound much

alike.

For altitude awareness during climb, pilots often call out

altitudes on the flight deck. The pilot monitoring may call

2,000 and 1,000 feet prior to reaching an assigned altitude.

The callout may be, “two” climbing through the transit

to go altitude (QNH), both pilots set their altimeters to

29.92 inches of mercury and announce “2992 inches” (or

‘standard, ’ on some aircraft) and the flight level passing.

For example, “2992 inches” (standard), flight level one

eight zero. The second officer on three pilot crews may

ensure that both pilots have inserted the proper altimeter

setting. On international flights, pilots must be prepared

to differentiate, if necessary, between barometric pressure

equivalents with inches of mercury, and millibars or

hectopascals, to eliminate any potential for error. For

example, 996 millibars erroneously being set as 2996.

For a typical IFR flight, the majority of in-flight time often

is flown in level flight at cruising altitude from top of climb

(TOC) to top of descent (TOD). Generally, TOD is used in

airplanes with a FMS and represents the point at which

descent is first initiated from cruise altitude. FMS also

assist in level flight by cruising at the most fuel saving

speed, providing continuing guidance along the flight plan

route including great circle direct routes, and continuous

evaluation and prediction of fuel consumption along with

changing clearance data.

Secondary area

Primary area holding pattern airspace area

Fix displacement area

Facility

Facility

Figure 2-70. Holding pattern design criteria template.

NOT FOR NAVIGATION

"...Hold southeast

of PINNE Intersection as published.

Expect further clearance at 1645."

There are at least three items in a clearance for a charted holding pattern:

• Direction to hold from the holding fix

• Holding fix

• Expect further clearance time

A clearance for an uncharted holding pattern contains additional information:

• Direction to hold from holding fix

• Holding fix

• The holding course (a specified radial,

magnetic bearing, airway or route number)

• The outbound leg length in minutes or

nautical miles when DME is used

• Nonstandard pattern, if used

• Expect further clearance time

"...Hold west

of Horst Intersection

on Victor 8

5 mile legs

left turns

expect further clearance at 1430."

Figure 2-71. ATC holding instructions.

Aircraft Speed and Altitude

During the en route descent phase of flight, an additional

benefit a FMS is that it provides fuel saving idle thrust

descent to your destination airport. This allows an

uninterrupted profile descent from level cruising altitude

to an appropriate MIA, except where level flight is required

for speed adjustment. Controllers anticipate and plan that

Figure 2-72. Clearance limit holding.

CHERRELYN

( H )117.2 CHL 331°

269°

221°

126°V214

the pilot may level off at 10,000 feet MSL on descent to

comply with the 14 CFR Part 91 indicated airspeed limit of

250 knots. Leveling off at any other time on descent may

seriously affect air traffic handling by ATC. It is imperative

that pilots make every effort to fulfill ATC expected actions

on descent to aid in safely handling and expediting air

traffic.

ATC issues speed adjustments if the flight is being radar

controlled to achieve or maintain required or desired

spacing. They express speed adjustments in terms of knots

based on indicated airspeed in 10 knot increments except

that at or above FL 240 speeds may be expressed in terms

of Mach numbers in 0.01 increments. The use of Mach

numbers by ATC is restricted to turbojets. If complying

with speed adjustments, pilots are expected to maintain

that speed within plus or minus 10 knots or 0.02 Mach.

Speed and altitude restrictions in clearances are subject

to misinterpretation, as evidenced in this case where a

corporate flight crew treated instructions in a published

procedure as a clearance. The aircraft was at FL 310 and

had already programmed the ‘expect-crossing altitude’ of

Maximum Holding Airspeed: KIAS5

Maximum Holding Airspeed: KIAS0

Maximum Holding Airspeed: KIAS0

14,001'

MSL

14,000'

MSL

6,000'

MSL

Minimum

Holding

Altitude

(MHA)

6,001'

MSL

Figure 2-73. Maximum holding speeds for different altitudes.

17,000 feet at the VOR. When the altitude alerter sounded,

the pilot advised Center that we were leaving FL 310. ATC

acknowledged with a “Roger. ” At FL 270, Center questioned

the pilot about the aircrafts descent. The pilot told the

controller that the reason for the descent was to cross the

VOR at 17,000 feet. ATC advised the pilot that he did not

have clearance to descend. What the pilot thought was a

clearance was in fact an “expect”clearance. Whenever pilots

are in doubt about a clearance it is imperative they request

clarity from ATC. Also, the term “Roger” only means that ATC

received the transmission, not that they understood the

transmission. “Expect” altitudes are published for planning

purposes and are not considered crossing restrictions until

verbally issued by ATC.

En Route Holding Procedures

The criteria for holding pattern airspace is developed

both to provide separation of aircraft, as well as obstacle

clearance. The alignment of holding patterns typically

coincides with the flight course you fly after leaving the

holding fix. For level holding, a minimum of 1,000 feet

obstacle clearance is provided throughout the primary

area. In the secondary area, 500 feet of obstacle clearance

is provided at the inner edge, tapering to zero feet at the

outer edge. Allowance for precipitous terrain is considered,

and the altitudes selected for obstacle clearance may be

rounded to the nearest 100 feet. When criteria for a climb

in hold are applied, no obstacle penetrates the holding

surface. [Figure 2-70]

There are many factors that affect aircraft during holding

maneuvers, including navigational aid ground and airborne

tolerance, effect of wind, flight procedures, application of

ATC, outbound leg length, maximum holding airspeeds,

fix to NAVAID distance, DME slant range effect, holding

airspace size, and altitude holding levels.

ATC Holding Instructions

When controllers anticipate a delay at a clearance limit or

fix, pilots are usually issued a holding clearance at least

five minutes before the ETA at the clearance limit or fix. If

the holding pattern assigned by ATC is depicted on the

appropriate aeronautical chart, pilots are expected to

hold as charted. In the following example, the controller

issues a holding clearance that includes the name of the

fix, directs the pilot to hold as charted, and includes an

expect further clearance (EFC) time. “Marathon five sixty

four, hold east of MIKEY Intersection as published, expect

further clearance at 1521. ”

When ATC issues a clearance requiring you to hold at a fix

where a holding pattern is not charted, pilots are issued

complete holding instructions. The holding instructions

include the direction from the fix, name of the fix, course,

leg length, if appropriate, direction of turns (if left turns

are required), and the EFC time. Pilots are required to

maintain the last assigned altitude unless a new altitude is

specifically included in the holding clearance and should

fly right turns unless left turns are assigned. Note that all

holding instructions should include an EFC time. In the

event that two-way radio communication is lost, the EFC

allows the pilot to depart the holding fix at a definite time.

Pilots should plan the last lap of the holding pattern to

leave the fix as close as possible to the exact time. [Figure

2-71]

When approaching the clearance limit and you have

not received holding instructions from ATC, pilots are

expected to follow certain procedures. First, call ATC

and request further clearance before reaching the fix. If

further clearance cannot be obtained, pilots are expected

to hold at the fix in compliance with the charted holding

pattern. If a holding pattern is not charted at the fix, pilots

are expected to hold on the inbound course using right

turns. This procedure ensures that ATC provides adequate

separation. [Figure 2-72] For example, the aircraft is heading

eastbound on V214 and the Cherrelyn VORTAC is the

clearance limit and the pilot has not been able to obtain

further clearance and has not received holding instructions,

plan to hold southwest on the 221° radial using left-hand

turns, as depicted. If this holding pattern is not charted,

hold west of the VOR on V214 using right-hand turns.

Where required for aircraft separation, ATC may request

that the pilot hold at any designated reporting point in a

standard holding pattern at the MEA or the MRA, whichever

altitude is the higher at locations where a minimum holding

altitude has not been established. Unplanned holding at

en route fixes may be expected on airway or route radials,

bearings, or courses. If the fix is a facility, unplanned

holding could be on any radial or bearing and there may

be holding limitations required if standard holding cannot

be accomplished at the MEA or MRA.

Maximum Holding Speed

The size of the holding pattern is directly proportional

to the speed of the aircraft. In order to limit the amount

of airspace that must be protected by ATC, maximum

holding speeds in knots indicated airspeed (KIAS) have

been designated for specific altitude ranges. [Figure 2-73]

Even so, some holding patterns may have additional speed

restrictions to keep faster aircraft from flying out of the

protected area. If a holding pattern has a nonstandard

speed restriction, it is depicted by an icon with the limiting

airspeed. If the holding speed limit is less than the pilot feels

necessary, advise ATC of the revised holding speed. Also, if

the indicated airspeed exceeds the applicable maximum

holding speed, ATC expects the pilot to slow to the speed

limit within three minutes of the ETA at the holding fix.

Often pilots can avoid flying a holding pattern, or reduce

the length of time spent in the holding pattern, by slowing

down on the way to the holding fix.

High Performance Holding

When operating at higher airspeeds, there are certain

limitations that must be adhered to. For example, aircraft

do not make standard rate turns in holding patterns if the

bank angle exceeds 30°. If your aircraft is using a flight

director system, the bank angle is limited to 25°. The aircraft

must be traveling over 210 knots true airspeed (TAS) for the

bank angle in a standard rate turn to exceed 30°; therefore,

this limit applies to relatively fast aircraft. An aircraft using

a flight director would have to be holding at more than

170 knots TAS to come up against the 25° limit. These true

airspeeds correspond to indicated airspeeds of about 183

and 156 knots, respectively, at 6,000 feet in a standard

atmosphere.

En Route Safety Considerations

Fuel State Awareness

In order to increase fuel state awareness, pilots are required

to monitor the time and fuel remaining during an IFR flight.

For example, on a flight scheduled for one hour or less, the

flight crew may record the time and fuel remaining at the

top of climb (TOC) and at one additional waypoint listed

in the flight plan. Generally, TOC is used in aircraft with an

FMS, and represents the point at which cruise altitude is first

reached. TOC is calculated based on current altitude, climb

speed, and cruise altitude. The pilot may elect to delete the

additional waypoint recording requirement if the flight is

so short that the record will not assist in the management

of the flight. For flights scheduled for more than one hour,

the pilot may record the time and fuel remaining shortly

after TOC and at selected waypoints listed in the flight plan,

conveniently spaced approximately one hour apart. The

actual fuel burn is then compared to the planned fuel burn.

Each fuel tank must be monitored to verify proper burn

off and appropriate fuel remaining. For two-pilot aircraft,

the pilot monitoring (PM) keeps the flight plan record. On

three-pilot aircraft, the second officer and PM coordinate

recording and keeping the flight plan record. In all cases,

the crew member(s) making the recording communicates

the information to the pilot flying.

Diversion Procedures

OpSpecs for commercial operators include provisions for en

route emergency diversion airport requirements. Operators

are expected to develop a sufficient set of emergency

diversion airports, so that one or more can be reasonably

expected to be available in varying weather conditions.

The flight must be able to make a safe landing, and the

airplane maneuvered off of the runway at the selected

diversion airport. In the event of a disabled airplane

following landing, the capability to move the disabled

airplane must exist so as not to block the operation of any

recovery aircraft. In addition, those airports designated

for use must be capable of protecting the safety of all

personnel by being able to:

• Offload the passengers and flight crew in a safe

manner during possible adverse weather conditions.

• Provide for the physiological needs of the passengers

and flight crew for the duration until safe evacuation.

• Be able to safely extract passengers and flight crew

as soon as possible. Execution and completion of the

recovery is expected within 12 to 48 hours following

diversion.

Part 91 operators also need to be prepared for a diversion.

Designation of an alternate on the IFR flight plan is a good

first step; but changing weather conditions or equipment

issues may require pilots to consider other options.

Original source PDFPublished from pages 106–112 of the recorded source chapter.
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