# Descending

I want to know that when should i start descent.
If my altitude is 36000 ft so what should be the distance to destination in nautical miles from where o should descent. And what should be the vertical speed while descending. And what should be the distance from which i should use and follow localiser and when should i turn off the autopilot system .And if you feel that something important for me as i am beginner, plz share it with me.

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Start descending about 36 mins before, with a -1000 fpm vertical speed.

To see how many mins (ete) you have left, hold your finger down on the bottom bar and find the “ETE TO DEST” Widget.

PS: 36000 ft is a bit high just saying

Is this what you mean?

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A nice method is to find the altitude to descend (approach height, so to roughly 3,000 feet, so descend 33,000 feet) then multiply by 3. This gives you 99 nm to descend. Descend at roughly 280 KIAS until 10,000, then at ~240 or so. As you descend, use you time to destination to find how fast to descend. If you have 20 minutes to descend 40,000 feet, then descend at about 2,000 ft/m.

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A lot of aircraft are able to cruise at around 40000 - in fact if you look on FR24 you’re bound to find a 787 which is flying at 43000.

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-2000, unless on the glideslope, is a pretty fast descent

I know, but I have no idea why you would…

You shouldn’t really be deacending at 2000fpm, that’s too steep.

Eh, not really. Staying below 2500 is usually fine.

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To save fuel, better winds maybe. This is getting a little off topic now. :)

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I never said you should…
Read the message I was replying to next time

I’m no expert, but this is what I do:

36000 x 3 = roughly 110.000
So start descending at 110NM out with 1200~1500fpm.
Slowly lower your speed so that at 10.000ft altitude your speed is less than 240 knots.

If this doesn’t work for you, try 36000 x 3.5 = roughly 120/130NM out.

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What would you suggest?

It’s a 3 degree slope no…?

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Yes, and I start at about 20 minutes out with a 1500 ft/min descent.
The following assumes landing without high terrain altitudes on descent.
Citatation X 527 kts GS (ground speed) at 35000 ft.,
I watch my airspeed, not to go above 280 kts.
Descend from 35000 ft to 15000 ft
AT 15000 ft change to 1000 ft/min airspeed at 260 kts to 10000 ft.
Then adapt to approach regarding terrain, airport elevation, windspeed, etc

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3 degrees is the the typical ILS glideslope, nothing to do with your descent from cruise

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Normally what I do is divide my altitude by 3, which is how many nmi out to start your descent.

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What I do might sound weird. Didn’t see anyone do it.
10 000ft - airport altitude= a
Current altitude-10 000 ft= b

For jet planes:
3a+ 5b= distance to start descending in nm

For dash 8:
3a+4b=distance to start descending in nm

I descend at -1500ft/min above 10 000 ft AGL and - 1000ft/min under 10 000ft AGL

Note:
I always start a bit early just in case… and also this isn’t the most realistic way, but I find it easier.

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yep thats the best way to plan it. If you read through the topic posted above as well will help with VS speed needed for the different stages of approach whihc changes (depends on your Ground Speed)

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