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glidslope questio


pollito

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if the angle at which you approach the runway must be 3 degrees, what do u need charts to know the altitude at which u can intercept the glidslope. at a given distance from the runway shouldn´t the intercepting altitude be the same for all runways in any airport?

also please tell me, how do you know the distance from where you are to a given close by airport or otherwise

thank you in advance.

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The glide slope angle is whatever the airport requires. Hilly terrain, buildings or other obstacles might require a steeper descent or even an indirect or "dog leg" approach to avoid a collision.

 

The same holds true for the intercept point.

 

As for distance from a nearby airport, you can use charts, the gps, the simulator's internal map, ils sytems, etc., etc.

 

A good start is reviewing the learning material built into the flight simulator.

 

Additionally, you might want to get copies of a couple of these free FAA publications:

 

https://www.faa.gov/regulations_policies/handbooks_manuals/aviation

 

https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak

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your right about your "the same" thinking.

 

for distance-vs-altitude:

work with a global number of 300ft per mile.

 

discribing here as if looking up frim along gliddslope:

1 Nm--300 ft

2 --------600 ft

3---------900 ft

4--------1200 ft

5--------1500 ft

6--------1800 ft

7--------2100 ft

8--------2400 ft

9--------2700 ft

10------3000 ft

 

so at 10 Nm out the glideslope is approx 3000 ft above the airports own altitude .

(3000 above the airports elevation above sealevel.)

 

(its actually a hair higher then 3000. But the list above is close enough, and is easy to remember and use during a busy descent to keep track of things. )

[sIGPIC][/sIGPIC]
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great and very good answer, I guess my theory would work only if the terrain was completly flat around the airport, I'll follow ur hints and for the time being I will work with the rule of 300 feet per mile.

thank you

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if the angle at which you approach the runway must be 3 degrees, what do u need charts to know the altitude at which u can intercept the glidslope. at a given distance from the runway shouldn´t the intercepting altitude be the same for all runways in any airport?

To elaborate a bit on what Ray said, the quick answer is NO. The angles are not necessarily the same, even at the same airport, though the "standard" is 3º, some may, due to obstructions, terrain, or other factors, need more or less (mostly more) -- perhaps there is steeper terrain on one approach needing, say, 4º to be safe. In addition, there may be slopes, such that not all touchdown zones are the same elevation, thus even at 3º requiring different altitudes.

 

And the charts have (for real life) a tremendous amount of other information that you need to do a proper, legal and safe instrument approach. Distance, assuming no GPS info, can be found by reading a DME, when the facility is properly euipped, but you can also use another VOR to find where you are (relative bearing, and a chart to find where the two cross, then it can be calculated. There are also Outer, Middle and sometimes Inner marker beacons whose distance from the field can be read on the chart, and ATC can tell you by radar. And these distances are not always the same on different runways or airports.

 

Charts also tell you what the minimums are for a given approach (not always 200 ft. on an ILS, and different on a localizer or back course approach), and they are not the same for all aircraft, mostly based on approach ground speed, and different yet for circling approaches.

 

Note, too, that I'm only scratching the surface for the information on those charts, and it's all needed for a safe approach.

 

But with that all said, it's your sim, so do what you wish -- physical safety isn't an issue there.

 

Larry N.

As Skylab would say:

Remember: Aviation is NOT an exact Science!

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