Final Approach Fix or Point
Thread Starter
Final Approach Fix or Point
Hi,
Can someone please explain why CatII approaches don't have a FAF while a CatI to the same runway often does?
I have had a look at Pans ops and I am still unsure.
Any info appreciated.
Cheers
Can someone please explain why CatII approaches don't have a FAF while a CatI to the same runway often does?
I have had a look at Pans ops and I am still unsure.
Any info appreciated.
Cheers
Thread Starter
Yes I am.
My understanding is that it is determined by the intersection of the 'not below' height for the intermediate section and the 3 degree glide slope.
Am I right that far?
My understanding is that it is determined by the intersection of the 'not below' height for the intermediate section and the 3 degree glide slope.
Am I right that far?
Join Date: May 2001
Posts: 10,815
Likes: 0
Received 0 Likes
on
0 Posts
Cat 1 approach plates normally have an Loc approach attached to them. The FAF is attached to the loc approach.
CAT II plates do not have anything else on them so don't have one.
It only really becomes an issue if you have some pillock of a TRE in the sim and they decide that the FAF indication has got something to do with the ILS procedure and the FAF is before 4DME 1000ft etc for the approach ban for the ILS. And they start bitching that you have made an illegal approach when the RVR is 500m.
If you get a pure CAT 1 plate where there is no loc approach is approved (I can't think of one off the top of my head) you won't see the FAF cross. You will need to look for a plate which just has ILS instead of ILS/LOC as the title.
CAT II plates do not have anything else on them so don't have one.
It only really becomes an issue if you have some pillock of a TRE in the sim and they decide that the FAF indication has got something to do with the ILS procedure and the FAF is before 4DME 1000ft etc for the approach ban for the ILS. And they start bitching that you have made an illegal approach when the RVR is 500m.
If you get a pure CAT 1 plate where there is no loc approach is approved (I can't think of one off the top of my head) you won't see the FAF cross. You will need to look for a plate which just has ILS instead of ILS/LOC as the title.
Join Date: Dec 2006
Location: Hamburg
Age: 46
Posts: 432
Likes: 0
Received 0 Likes
on
0 Posts
Nothing to to with CAT I or CAT II/III. Non-precision approaches have final approach fixes, precision approaches have final approach points.
The final segment of a precision approach starts where the nominal glide path intersects the intermediate flight altitude. However, the height of this altitude will vary depending on atmospheric conditions. On a cold day, an altitude of 3000 feet will be lower than a geographical height of 3000 feet, higher on a warm day. Hence, the glide path will be intercepted at different points and it doesn't make sense to publish a fix.
In a non-precision approach, on the other hand, there is no vertical guidance, i.e. no glide path. The final approach begins over the final approach fix, which is a defined geographical location and marked on approach charts with the Maltese Cross.
The final segment of a precision approach starts where the nominal glide path intersects the intermediate flight altitude. However, the height of this altitude will vary depending on atmospheric conditions. On a cold day, an altitude of 3000 feet will be lower than a geographical height of 3000 feet, higher on a warm day. Hence, the glide path will be intercepted at different points and it doesn't make sense to publish a fix.
In a non-precision approach, on the other hand, there is no vertical guidance, i.e. no glide path. The final approach begins over the final approach fix, which is a defined geographical location and marked on approach charts with the Maltese Cross.
Join Date: May 2001
Posts: 10,815
Likes: 0
Received 0 Likes
on
0 Posts
Not a problem
But I would say that the FAF in some cases is not the point of decent of the ILS it can be anywhere depending on the approach design. In CAT A airports in Europe 99% of the time it is where you start your final approach decent which would be when you intercepted the ILS.
But if you say have a none DME timed procedure to an ILS your FAF is at the locator which you go out bound and start your timing from for the Loc approach and nowhere near the inbound once your actually on the Loc.
But I would say that the FAF in some cases is not the point of decent of the ILS it can be anywhere depending on the approach design. In CAT A airports in Europe 99% of the time it is where you start your final approach decent which would be when you intercepted the ILS.
But if you say have a none DME timed procedure to an ILS your FAF is at the locator which you go out bound and start your timing from for the Loc approach and nowhere near the inbound once your actually on the Loc.
