Enroute Phase - P-8210071

RADIO INSTRUMENTS

CHAPTER THREE

IFR Departure

The student will utilize the VT-86 In-Flight Guide to complete required crew communications

and checklists, and will provide requests for headings and altitudes as required to navigate

through the departure.

Altimeter Procedures

From the surface to 18,000 feet MSL, the current altimeter setting of a station along the route of

flight and within 100 miles shall be used. In the event of two-way radio failure, the forecast

altimeter setting obtained from the weather brief should be used.

At or above 18,000 feet MSL, an altimeter setting of 29.92 shall be used and all references to

altitudes shall be in flight levels. This procedure applies to the National Airspace System in the

United States. It does not apply to Warning Areas outside the U.S.

When the local barometric pressure is lower than 29.92 certain flight levels are not useable

below 18,000 feet MSL. Under these conditions, it would be futile to request or file one of those

flight levels as a cruising altitude. In case the correct altitude for two-way radio failure is

determined to be the "Minimum altitude converted if appropriate, to minimum flight level for

IFR operations..." the Flight Information Handbook contains procedures for determining the

lowest useable flight level when the barometric pressure is below 29.92.

307. ENROUTE PHASE

This section contains procedures for the enroute phase of a Radio Instrument event, and

describes activities which normally take place after completion of a departure and before

terminal activities commence.

Tracking

To describe a student's tracking responsibilities, a review of some common navigation terms is

in order:

1. HEADING - The direction an aircraft is pointed, usually expressed in degrees magnetic

from North.

TRACK - The flight path of an aircraft over the surface of the earth.

COURSE - Intended track of an aircraft over the surface of the earth.

ROUTE - a defined path consisting of one or more courses.

5. BRACKETING - the changes of heading in the search for a drift correction angle which

will hold an aircraft on course.

RADIO INSTRUMENTS

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