Intermediate Fix and lateral safety margin.
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Joined: Jan 2016
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From: Lonely planet
Intermediate Fix and lateral safety margin.
Anybody know the width of the IF safety margin in NM? The Jepp mentions a lateral safety margin on 2.5 nm either side of the track for the IAF, and an extra 2.5nm secondary buffet margin.

Joined: Jan 2008
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From: Scotland
It depends on the approach, is it straight in, NDB, VOR. For a VOR approach it will taper from the IAF to the IF in the primary area from 2,5 nm to 1 nm and the secondary area from 2,5 to 0,5 nm either side of track. NDB from 2,5 to 1,25 nm in the primary area and from 2,5 to 1,25 in the secondary area
Last edited by Edgington; 16th October 2024 at 16:49.

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From: UK
If I am not wrong, the safety margin is usually 2.5 NM either side of the track, as you mentioned for the IAF.
Thread Starter

Joined: Jan 2016
Posts: 103
Likes: 2
From: Lonely planet
It depends on the approach, is it straight in, NDB, VOR. For a VOR approach it will taper from the IAF to the IF in the primary area from 2,5 nm to 1 nm and the secondary area from 2,5 to 0,5 nm either side of track. NDB from 2,5 to 1,25 nm in the primary area and from 2,5 to 1,25 in the secondary area

Joined: May 2006
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From: Australia
2.5nm either side at the IF, and reduces linearly down until intercept of the ILS OAS contours. The width is variable depending on the parameters of the ILS but is typically about 1.5NM at the FAF and reduces further down to the MAPt.
I cant seem to post an image. But PANS-OPS Figure II-1-1-2 gives you a good idea of how it works
Alpha
I cant seem to post an image. But PANS-OPS Figure II-1-1-2 gives you a good idea of how it works
Alpha





