Simviation Forums

when descending a twin prop aircraft what is the descent rate.If I am normally 3000ft altitude about
10nm from runaway is it correct altitude to start a descent.

Hey mate....

You should start your descend as soon as you get to the final approach leg (which is the beging of the green cone in your GPS monitor).
the descend rate on the final approach leg should be
+/-700 fpm.


Liran Bar, Israel

Hey, Wace

You can also download descent calculators

(e.g. http://www.angelfire.com/mi/flightsim13/utilities.html).

These take care of the mathematical equations -- which can make it easier particularly when you fly the big ones and have to start descending from tens thousands of feet.

Wace, it really depends on your ground speed. If you're doing 50knots you need only descent at 250fpm but if you're doing 1000knots you'll need about 5000fpm or you'll overshoot!!

I've found a common formula on the forums abit lately, relating to this topic. Its goes closely as follows:
Say your at FL30,000. You drop the last 3 zero's, and then multiply 30X3, which equals 90. So then you start your desent at about 90nm from your dest.
Your at 5,000,   5X3=15.
Hope this helps.  8)

Thanks for the replies on descent rate,
the suggestions on the green gps cone & calculations to descend based on altitude & speed were really helpful

Maybe it's just me, but 5,000 f.p.s. seems awful fast.

I fly the "heavies" almost exclusively, so the max rate of decent I hit is never over 2,500 f.p.s.
And, that's pushing it well over the normal 1,800 f.p.s. decent from cruise altitude.

Fisharo - it was just an example! I'd only ever descend at 5000fpm if I'd opened the door and jumped  :)

My point was that if you know your ground speed you can calculate your ideal Vertical speed

If you can find it (as usual I don't know where I got it from), there's a gauge that does it for you:

DescCalculator.gau

It's a digital readout and works very well.

When I was talking to Rob Barendregt about the gauges for the Baron panel, I suggested he might have a go at a more uptodate version. We can only wait and see.

Speedbird_03;

Sorry. I see now.

But you know that there are some people out there that slam on full flaps, drop the gear and nose dive from 30,000 ft.

 Al