7110.65R

TBL 1-1-1

VOR/DME/TACAN Standard Service Volumes

SSV Designator
T (Terminal)
L (Low Altitude)
H (High Altitude)

VL (VOR Low)

VH (VOR High)

DL (DME Low)

DH (DME High)

Altitude and Range Boundaries
From 1,000 feet ATH up to and including 12,000 feet ATH at radial distances
out to 25 NM.
From 1,000 feet ATH up to and including 18,000 feet ATH at radial distances
out to 40 NM.
From 1,000 feet ATH up to and including 14,500 feet ATH at radial distances
out to 40 NM. From 14,500 ATH up to and including 60,000 feet at radial dis
tances out to 100 NM. From 18,000 feet ATH up to and including 45,000 feet
ATH at radial distances out to 130 NM.
From 1,000 feet ATH up to but not including 5,000 feet ATH at radial distances
out to 40 NM. From 5,000 feet ATH up to but not including 18,000 feet ATH at
radial distances out to 70 NM.
From 1,000 feet ATH up to but not including 5,000 feet ATH at radial distances
out to 40 NM. From 5,000 feet ATH up to but not including 14,500 feet ATH at
radial distances out to 70 NM. From 14,500 ATH up to and including 60,000
feet at radial distances out to 100 NM. From 18,000 feet ATH up to and includ
ing 45,000 feet ATH at radial distances out to 130 NM.
For altitudes up to 12,900 feet ATH at a radial distance corresponding to the
LOS to the NAVAID. From 12,900 feet ATH up to but not including 18,000
feet ATH at radial distances out to 130 NM
For altitudes up to 12,900 feet ATH at a radial distance corresponding to the
LOS to the NAVAID. From 12,900 ATH up to and including 60,000 feet at ra
dial distances out to 100 NM. From 12,900 feet ATH up to and including
45,000 feet ATH at radial distances out to 130 NM.

d. Nondirectional Radio Beacon (NDB) SSVs.
NDBs are classified according to their intended use.
The ranges of NDB service volumes are shown in

TBL 1-1-2. The distance (radius) is the same at all
altitudes for each class.

TBL 1-1-2

NDB Service Volumes
Class

Distance (Radius) (NM)

Compass Locator
MH
50*
HH
*Service ranges of individual facilities may be less than 50 nautical miles (NM). Restrictions to service
volumes are first published as a Notice to Air Missions and then with the alphabetical listing of the NAVAID
in the Chart Supplement U.S.

1-1-9. Instrument Landing System (ILS)
a. General
1. The ILS is designed to provide an approach
path for exact alignment and descent of an aircraft on
final approach to a runway.

1-1-10

2. The basic components of an ILS are the
localizer, glide slope, and Outer Marker (OM) and,
when installed for use with Category II or Category
III instrument approach procedures, an Inner Marker
(IM).

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