Instrument Flight
Flight Procedures
The correction factor is calculated as follows:
Inbound turn correction factor = ([90 + Lead (radials)] / 90) x (Turn Radius)
Outbound turn correction factor = ([90 - Lead (radials)] / 90) x (Turn Radius)
Example:
An inbound turn of more than 90 degrees on a 10 DME arc at 250 KGS:
Correction Factor = ([90 + 15] / 90) x 2.5 = 2.9
Therefore, the correct lead for an inbound turn at 10 DME =
15 (lead for 90 degree turn on 10 DME arc) + 2.9 = 17.9, or approximately 18 radials (see chart below)
An outbound turn of less than 90 degrees on a 10 DME arc at 250 KGS:
Correction Factor = ([90 - 15] / 90) x 2.5 = 2.08
Therefore, the correct lead for an outbound turn at 10 DME =
15 (lead for 90-degree turn on 10 DME arc) - 2.1 = 12.9, or approximately 13 radials (see chart below)
Approximate Lead Radials for 250 KGS Arcing Around a NAVAID:
INBOUND TURN
OUTBOUND TURN
ARC DME
90 DEGREE TURN
(>90 DEGREES)
(<90 DEGREES)
20
7.5
N/A
N/A
15
10
N/A
N/A
10
15
18
13
7
21
27
16
5
30
40
20
POINT-TO-POINT NAVIGATION
As you approach a terminal area, the controller may clear you either to a holding fix or to the IAF. When
cleared direct to a fix, you will have to use radar vectors, traditional point-to-point navigation, or waypoint
offset navigation to navigate to the fix.
(4-01) Original
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