# AI A/C, wind and ILS

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So I was flying into KFNL For Collins/Loveland here in northern Colorado. About 20 miles out I listened to AWOS and the wind was about 130/5 or so. So I knew I had to land on 15 and not 33. 33 has the ILS and 15 is just back course. Despite me doing the right thing by landing into the wind, AI A/C were landing on 33!

So my question: Does an ILS precede a runway at a certain wind speed? Like if the wind is at or below 10 KNTS the ILS will precede even though the wind is at the opposite direction for AI landings?

Also, I can't for the life of me remember what base, crosswind and downwind was. Does anybody have a circuit diagram I can look at so I know next time. I was parallel to the runway and I couldn't quite remember if I was to say I was downwind, crosswind or on base.

Thanks!

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As far as winds are concerned FSX will favor active runways with ILS if there are no winds or if the winds are light. As far as flying the pattern.....Landing 15, (with 33 being the other end of the runway of course) heading 330 would be downwind. A right base would be 330+90=60 degrees then final 60+90=150 degrees. A left base would be 330-90=240 degrees with a final 240-90=150 degrees.
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Thanks! Now I know what to say! I figured perhaps ILS took precedence with light winds.

What's the difference between crosswind and base?

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What's the difference between crosswind and base?

Opposite directions. Crosswind leg is what you turn onto shortly after takeoff (90Âº left or right, left for left traffic), while base is the leg 90Âº to, and going toward, final and is just before turning final. The four traffic pattern legs are designated based on a square (4 legged) pattern, but it's possible to use a portion of the pattern and each leg remains the same name/direction as if you were in the square pattern.

BTW, that leg just after takeoff is the upwind leg, but that designation also applies if you are off to the side of the runway opposite the downwind leg. Do notice that all the legs, except final, are named relative to the wind (wind assumed down the runway).

Larry N.

As Skylab would say:

Remember: Aviation is NOT an exact Science!

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BTW, that leg just after takeoff is the upwind leg, but that designation also applies if you are off to the side of the runway opposite the downwind leg. Do notice that all the legs, except final, are named relative to the wind (wind assumed down the runway).

I'm not understanding. If I take off 15 that is upwind, correct? Downwind would be going towards 33 to land on 15?

I would say crosswind if I make a left or right turn after upwind?

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This picture:

shows a left hand pattern. A right pattern is the same, except all turns are to the right. The picture is from this Wikipedia article on traffic patterns.

Note that the one they show as "departure" is also sometimes called "upwind."

Larry N.

As Skylab would say:

Remember: Aviation is NOT an exact Science!

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That makes more sense, thanks. So from that picture the plane is on left base?
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One of them is -- there are five planes there.

Larry N.

As Skylab would say:

Remember: Aviation is NOT an exact Science!

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This one?

http://i.imgur.com/REoHsLX.png

Also, without creating another thread. Am I correct in saying to intercept the glideslope you should be at 1,800 feet above the airport altitude? It seems that way and I think I read that somewhere. I've always did 1,800' and never missed the GS.

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Yes, that one is left base. To intercept the glide slope, you need to be below it at the time of intercept. 1800 AGL will do it if you're far enough out. That glide slope is usually a 3Âº slope, so the further from the airport, the higher you can be, so long as you're well within reception range.

But note that instrument approach charts actually tell you both the path to intercept the localizer and the altitude for intercepting the glide slope, along with much else.

Larry N.

As Skylab would say:

Remember: Aviation is NOT an exact Science!

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I never realized that the approach chart had that. I think I remember seeing it. Nice to know. I downloaded an App for my phone that will show aeronautical charts, plates, etc. Really nice to have if I'm on VATSIM. I like to go back to VATSIM once I get the PMDG 737NGX. I only flew once with VATSIM in FS2004 with the PMDG 737.
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This one?

http://i.imgur.com/REoHsLX.png

Also, without creating another thread. Am I correct in saying to intercept the glideslope you should be at 1,800 feet above the airport altitude? It seems that way and I think I read that somewhere. I've always did 1,800' and never missed the GS.

You need to change your thinking. An approach chart calls for a "specific" altitude MSL for the Initial Approach Course. You are supposed to be at that altitude when intercepting the Glide Slope. For example, Denver Int'l (DEN), the Initial Approach Course altitude is 9,000 ft. Your 1800' method puts you about 4000' underground. So, find the proper approach charts and fly it exactly as prescribed (or altitude as assigned by ATC). Gipper

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I said, "1,800 feet above the airport altitude."
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I said, "1,800 feet above the airport altitude."

You did, indeed, say that. But Gipper is pointing out that, in real life, that would not be a good choice. As you have stated it, if you were on final for runway 08 at Boulder, CO airport (now KBDU, was 1V5) at 7088 feet and 10 miles out, you'd be in the rocks.

I illustrated Boulder because I know the details, but there are numerous airports where there is a similar situation.

I'll grant you that usually, in the sim, it can be a workable idea, although there are places it can't work, as I mention above. But in the real world, the approach plate does, indeed, give you the altitudes you should fly and where. One size does not fit all.

Larry N.

As Skylab would say:

Remember: Aviation is NOT an exact Science!

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Here is something worth thinking about. The glide slope for an ILS approach most of the time is 3Âº. That equals about 320ft vertical height per nautical mile. Most intercepts are designed to occur around 10nm out from the runway threshold. That means you should be flying at least 3200ft agl, on interception of the glide slope. Your 1800ft agl intercept puts you less that 6nm from the runway. In real life, that just never happens. Happy flying. Gipper
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You did, indeed, say that. But Gipper is pointing out that, in real life, that would not be a good choice. As you have stated it, if you were on final for runway 08 at Boulder, CO airport (now KBDU, was 1V5) at 7088 feet and 10 miles out, you'd be in the rocks.

I illustrated Boulder because I know the details, but there are numerous airports where there is a similar situation.

I'll grant you that usually, in the sim, it can be a workable idea, although there are places it can't work, as I mention above. But in the real world, the approach plate does, indeed, give you the altitudes you should fly and where. One size does not fit all.

In that case, yeah, that would make sense. Aspen is another hairy one. It's just been in my experience in the sim that my final altitude was around 1,800' above the airport elevation. In real life you would most definitely look at the plate. That's what I would do. Especially a Boulder or Aspen approach. Holy cow!

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