VirtualHub

Hello 👋 so I was using VirtualHub and I was wondering how the TOD works because it says (EX)”50NM” needed and it tells you the feet per minute when you put all the info

This photo is all a example

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Where does it say (EX)”50NM”?
What do you not understand about it?

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No I was using as a example to show

Every number is a example just to show

But my problem is how it works mainly what —- needed means

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That’s the distance you’ll cover during your descent

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Not following

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So the distance you’ll cover when you descend from 34000-12000 is 73NM

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Got it but now isn’t TOD supposed to tell you what NM you descend at

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The “-” 1700FT means that you’ll need to descend at a negative rate,

The “73NM” is the distance that you would go over from the TOD, to your indicated ending altitude (planned altitude = FL120)

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No, you TOD is 73 nm out of your planned altitude. Thats why its generally better to plan an altitude and assign it at a waypoint or destination (ICAO of airport)

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So I’m just confused what NM you descend at (generally)

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Ok, so lets say were cruising from Taipei to Hong kong at a fixed altitude of FL350 (35K)

We are planning on descending at a V/S of -2000. When we imput all of the numbers into the calculator;


Planned altitude = 3000ft (intercepting ILS at VHHH)
Cruising altitude = 35,000ft
Speed = 240


After we’ve imputed this, I have gotten:

Vertical speed = -2000
Distance needed = 106 nm.

The 106NM is the field of space needed for us to successfully reach out planned descent (FL30) from our TOD (FL350). So, we’ll start our descent when we are 106 nm out of the airport VHHH.


I hope this helps.

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Theres no “generally” as there are factors as cruise speed, descent speed, cruise altitude, planned altitude, traffic, and more that can affect out TOD.

I would say that perhaps the general would be anywhere from 200nm – 100nm If we are cruising at a relative normal altitude FL28 – FL430

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What happens when it’s Mach

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You just take the speed from your HUD (Indicated airspeed)

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Ok can u pm me for tutorial on the calculator, if your not busy

I’ve practically gave you one :

All my questions are answered

You can just type in 35 000 ÷ 1700 and then you will get 20,5 , that means 20,5 is ETE 20 min and 30 sec to the destination airport you shall decend.
I usually add this to my calculation:
35 000 ÷ 1700 + 5 or 4 to get some margins with traffic

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