Simviation Forums

Can anyone help me with making decents in heavy jets. Usually when crusing at between FL320 and FL350 I usually start my decents 200nm out. This usually brings me down to final approach altitude about 50nm away from the airport resulting in a boring crawl at 250knots for 50 miles! So the obvious answer here is to start the decent 150nm out rather than 200! But does anyone know of the correct proceedure for decents in heavies, such as distances, decent rates etc. I would look it up on the FS Help centre, but im not at home right now and am bored

John

The governing principle (in real life too) is the 'Rule of Three', jb.

An aeroplane normally descends 1,000 feet for every three miles travelled.

Nav is correct in what he said the only problem is that some of the craft you download does not have the correct rate for descent or climb. I have seen more than one 747 that will have a rate set at 700ft per min which is crazy in order to fix this you have to change the aircraft cfg file to put the proper entry in use the default aircraft as a guide simalar craft will use the same rates.
You can as Nav said alter the rate of climb or descent but it will go back to the set rate the next time you have to climb or descend untill you change the rate in the aircraft cfg file.

....Nav is right of course...he does know his theory, but unfortunately he sometimes tends forget we are flying a SIMULATOR...and again unfortunately, as gary says some of these FS aircraft do not match up to real life

  ..mmm..I wonder...Does FS9 really make adjustments for the air density at differing levels......commoner  ;)

And if you don't have time for the math, here's a quicker way-

When you're cruisng at FL310, ATC will order you to descend at 100 nm out. Add +/- 5 nm for each 1,000 ft of cruisng alt.  For example-

FL320 - 105 nm
FL350 - 120 nm
FL280 - 85 nm

Works like a charm, every time.

usually when im flying with ATC, i simply wait until the controller tells me to descend.... most times it knows what it's doing and all goes well.
i then reduce my speed to 250 kts, which seems to be the speed the ATC reacts best to.
it also seems to react best to 1800 vertical speeds...

on earlier versions of FS (no ATC), i used the 3 to 1 rule... but with ATC it is not necessary... if you use it , the controller will probably tell you to stop it and follow HIS directions

c ya

Moach

Oddly enough, when I use the AP in the POSKY 747-400 it defaults to 800 fpm up or down... seemed low to me, but it worked out pretty well, actually, although ATC always tells me to "expedite" long after she's started descending...

[quote]

I use two simple rules when planning a decent:-

Distance Out
To figure out when to start my decent I use the FL/3 rule explained above. (eg FL300/3=100nm)

Vertical Speed
To get a nice decent profile that  I use a simple rule: vspeed = groundspeed x 5 (eg 250kts x 5 = 1250fpm). As your speed slows for the final segments and approach so will your vspeed. In my B737 my approach speed of 140kts gives a fairly standard 700fpm at touchdown.

As with all of these rules they're really just approximations, you learn from experience how to use them.

Happy flying!

Haven't you read all the 'Help please!' threads on here, from people who've been screaming along at 40,000 feet and 350 knots Indicated, asking why the wings keep falling off?  :)  

Honestly, I know they're n00bs, but they annoy me.  :P

(uberjk )

Honestly, I know they're n00bs, but they annoy me.

Well that's'a nice attitude...
Come on Beefhole, that is just stupid to write something like that. What do you want to prove?
Do not forget that you are a "n00b" (as you'd like to call it) yourself.

No reason for that behavior, not everyone can be all-knowing like you, can they?

About the descents anyways,

The rule of three's is standard in jets. Might I add we don't acknowledge ATC all the time. They will issue the clearance and we may toll along for a few more miles before descending, pilot's preference really. As soon as the descent starts, crank it back to 250 indicated. Jet standard descent rate is 1,800 feet per minute. 250 indicated and 1,800 feet a minute will land you perfectly out (about 20 miles out or so you'll be at your pattern altitude) and ready to begin approaching, conveniently with the FS2004 ATC will usually clear you for an approach.

Well that's'a nice attitude...
Come on Beefhole, that is just stupid to write something like that. What do you want to prove?
Do not forget that you are a "n00b" (as you'd like to call it) yourself.

No reason for that behavior, not everyone can be all-knowing like you, can they?

yay, here we go again.  I'll make it quick.

First off, it was meant to be taken tongue in cheek.  I'll add more smileys.

Yes, I was a noob once, and I figured these things out for myself.  Not that there's any problems with asking.

Not trying to prove anything, don't spin this on me.

And as for the last thing, no, it's the Torphy genetics.  Only my bloodline has the all-knowingness; everyone else is below us.

EDIT: K, that last one was jking too, and I'm really sorry for this post, I just wanted to get it out of the way.  Shoulda PMed ya dude, too late now.  Now I ahve to add something on descents to make the post legit-

I agree with Saratoga.  That's why the default VS on boeing planes is -1800, and it works too-just dial it back to about -1200 when you get a descent order below about 10,000 ft AGL.  Works for me.

RE-EDIT: Ok, just restarted my comp to do this, so here goes: Nexus, you're correct.  As my comment stood, it was out of line.  There. My mom just yelled at me.  Cool.

Beef, I have nothing against you. It's just that I believe it's important to be civil and friendly to eachother.  :)
Aviation is a complicated field to grasp, and a "stupid" question for you, may be the world's most complicated thing for another.

To write that beginner's annoy you is not really the way to attract members and encourage newcomers to post.  :)

And yes - I over reacted aswell, it's hard to to intrepret one's sense of humour over the internet. Smileys help, but misunderstandings are prone to happen  :)