| Home | Privacy | Contact |

Instrument Flying Handbook
IFR Flight
Clearances

| First | Previous | Next | Last |

Instrument Flying
Handbook

Preface

Table of Contents

Chapter 1. Human Factors
Chapter 2. Aerodynamic Factors
Chapter 3. Flight Instruments
Chapter 4. Section I
Airplane Attitude Instrument
Flying
Using Analog Instrumentation
Chapter 4. Section II
Airplane Attitude Instrument
Flying
Using an Electronic Flight
Display

Chapter 5. Section I
Airplane Basic
Flight Maneuvers
Using Analog Instrumentation
Chapter 5. Section II
Airplane Basic
Flight Maneuvers
Using an Electronic Flight
Display

Chapter 6. Helicopter
Attitude Instrument Flying

Chapter 7. Navigation Systems
Chapter 8. The National
Airspace System

Chapter 9. The Air Traffic
Control System

Chapter 10. IFR Flight
Chapter 11. Emergency
Operations

The term "cruise' in this clearance means a pilot is authorized
to fly at any altitude from the minimum IFR altitude up to and
including 5,000 feet, and may level off at any altitude within
this block of airspace. A climb or descent within the block may
be made at the pilot's discretion. However, once a pilot reports
leaving an altitude within the block, the pilot may not return to
that altitude without further ATC clearance.

When ATC issues a cruise clearance in conjunction with an
unpublished route, an appropriate crossing altitude will be
specified to ensure terrain clearance until the aircraft reaches a
fix point, or route where the altitude information is available.
The crossing altitude ensures IFR obstruction clearance to
the point at which the aircraft enters a segment of a published
route or IAP.

Once a flight plan is filed, ATC will issue the clearance with
appropriate instructions, such as the following;

"Cessna 1230 Alpha is cleared to Skyline airport via
the Crossville 055 radial, Victor 18, maintain 5,000.
Clearance void if not off by 1330."

Or a more complex clearance, such as:

"Cessna 1230 Alpha is cleared to Wichita Mid-continent
airport via Victor 77, left turn after takeoff, proceed
direct to the Oklahoma City VORTAC. Hold west on
the Oklahoma City 277 radial, climb to 5,000 in holding
pattern before proceeding on course. Maintain 5,000 to
CASHION intersection. Climb to and maintain 7,000.
Departure control frequency will be 121.05, Squawk
0412."

Clearance delivery may issue the following "abbreviated
clearance" which includes a departure procedure (DP):

"Cessna 1230 Alpha, cleared to La Guardia as filed,
RINGOES 8 departure Phillipsburg transition, maintain
8,000. Departure control frequency will be 120.4,
Squawk 0700."

This clearance may be readily copied in shorthand as follows:

"CAP RNGO8 PSB M80 DPC 120.4 SQ 0700."

The information contained in this DP clearance is abbreviated
using clearance shorthand. The pilot should know the locations of
the specified navigation facilities, together with the route and
point-to-point time, before accepting the clearance.

The DP enables a pilot to study and understand the details
of a departure before filing an IFR flight plan. It provides
the information necessary to set up communication and
navigation equipment and be ready for departure before
requesting an IFR clearance.

Once the clearance is accepted, a pilot is required to comply
with ATC instructions. A clearance different from that issued
may be requested if the pilot considers another course of action
more practicable or if aircraft equipment limitations or other
considerations make acceptance of the clearance inadvisable.

A pilot should also request clarification or amendment, as
appropriate, any time a clearance is not fully understood
or considered unacceptable for safety of flight. The pilot is
responsible for requesting an amended clearance if ATC issues
a clearance that would cause a pilot to deviate from a rule or
regulation or would place the aircraft in jeopardy.

Clearance Separations
ATC will provide the pilot on an IFR clearance with separation
from other IFR traffic. This separation is provided:

1. Vertically- by assignment of different altitudes.

2. Longitudinally- by controlling time separation between
aircraft on the same course.

3. Laterally- by assignment of different flight paths.

4. By radar- including all of the above.

ATC does not provide separation for an aircraft operating:

1. Outside controlled airspace.

2. On an IFR clearance:

a) With "VFR-On-Top" authorized instead of a
specific assigned altitude.

b) Specifying climb or descent in "VFR conditions."

c) At any time in VFR conditions, since uncontrolled
VFR flights may he operating in the same
airspace.

In addition to heading and altitude assignments, ATC will
occasionally issue speed adjustments to maintain the required
separations. For example:

"Cessna 30 Alpha, slow to 100 knots."

A pilot who receives speed adjustments is expected to maintain
that speed plus or minus 10 knots. If 'for any reason the pilot
is not able to accept a speed restriction, the pilot should advise
ATC.

At times, ATC may also employ visual separation techniques
to keep aircraft safely separated. A pilot who obtains visual
contact with another aircraft may be asked to maintain visual
separation or to follow the aircraft. For example:

"Cessna 30 Alpha, maintain visual separation with that
traffic, climb and maintain 7,000."

 
10-4