What speed to Decent?

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When ever we start the decent what speed do we Decent?

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There was just a post on this 30mins ago please search before posting.

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I had check that tool out but it doesn’t say what speed

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@Sashaz55 linked a good topic to continue discussions in.

You could utilize third party apps and websites to mirror speeds from real routes. FPLTOIF is a great site created by Chris_S as well :)

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Thank you for Help

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Depends on the altitude and ETE to Dest. But I used to descend with -1400 ft/min…

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Try this out:

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Your VS is actually dependent on your speed, therefore as long as you have set the AP to whatever you want your descent rate to be then you can vary your speed however you like and your VS will react accordingly.

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With reference to real life proceedures,here is a quick details on descend:

Calculating TOD:

One of the important part is calculation of TOD,it differs with reference to the degree glide the pilot wants,however most airliners or GA prefers 3 degree glide.using 3 degree glide,here is a formula:

D(nm)= Cruise altitude-fix altitude * Descend angle/(majority preference is 3degree)*100

Example: I am cruising at FL340 and wanna go all way down to FL60 in a 3degree glide,so by applying the above mentioned formula,we will get:

D(nm)= 34000-6000 /3*100= 93.33 or 93 NM

So we got the answer.To descend to FL60 from FL340, it will take 93 nautical miles if applying 3degree descent angle

Now,here’s how you will determine the VS for descend:

With same details above,we will calculate descend rate:

VS(ft/min)- 5%(descent rate%).Note: 3 degree angle = 5% Descent rate,an explanation for future :)) * ground speed

                                                             or  5*ground speed

Assuming GS400, we want to descend to FL60 therefore descend VS will be

5 * 400=2000 fpm,so descend at 2000fpm all the way maintaining the VS as per the rule with reference to your GS

Happy landings.

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What speed to descend? Airspeed or VS/vertical speed? I use these ball park number for medium and heavies. It depends.

Cruise to 29000ft = mach .80+
29000 to 15000ft = 300knts
15000ft to 12000 = 270/280
11000 to 5000ft = 240/230
5000ft to 4000ft = 230/200
4000ft to rwy = approach/landing speed.

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