X-ing restrictions

[Nindiri]

FMS inop?

Declare an emergency!

 

[ArcticFlier]

3.8 degree gs gives us about 2700 to 3100 fpm in the CRJ. Works fine for me.

I use altitude to lose times 3 if the box takes a dump. Add or subtract 1 nm for every 10 knots of headwind or tailwind. Works pretty well.

If you have to slow as well, get down early (1 nm for every 10 knots to slow) ie slowing from 320 to 250 takes 7 nm at roughly 80% N2. It's about the only time I use N2 for anything like this.

AF

 

[scotts]

If you need to do over 3000 fpm on a 3 degree descent, that implies you're doing over 600 kts gs. I'm guessing the math is screwed up somewhere........

...Hope this helps,

BR

It's closer to a 4.0 degree G/S. Used if you want to descend at idle vs. with power applied during the descent. Rate of descent varies between about 2800 and 3500.

FWIW...

 

[CitationLover]

As is the grey matter 'tween your ears that you will rely on when the box takes a dump. Helps to keep it tuned up and runnin' right....

Now where'd I put that Gingko Biloba?

well you can always double check yourself WHILE using the FMS.

and they wonder why missed restrictions lead the ASAP reports.........

and besides these are meticulously maintained airplanes. nothing ever "takes a dump".

 

[DC8 Flyer]

4 times the altitude to loose. IE 350 and need to cross XYZ fix at 11000, equals 24 * 4 = 96 miles. Works for most almost any airspeed and groundspeed. 9 times out of 10 you will be early by about 10 or 15 miles.

Forget trying to get the fix at the altitude be early by a few miles. Especially when you get a crossing clearance below 10000 this gives you plenty of time to hit 11000 and start slowing to 250 and still make the restriction.

 

[CAVOK69]

It's closer to a 4.0 degree G/S. Used if you want to descend at idle vs. with power applied during the descent. Rate of descent varies between about 2800 and 3500.

FWIW...

if you use your altitude times 3 that will give u a 3 degree glide path, it is up to you to maintain that. i use gs divided by 2 for rate of descent. But honestly, even if you are doing 3000fpm, so what? Back in my lear 35 days( running on fumes) we would do idle throttle descents giving us an 8000fpm descent no 3 to 1... a 1.5 to 1 is what we would use. most fuel efficient type of descent is idle throttle as long as you start it at the right distance.

 

[FSB99]

some of you guys sound like you're saying 3000 fpm or descent is a bad thing.. it's a jet. flight idle, or at least very low thrust ain't gonna shock cool the motors, and it saves gas, keeps you on the required glide path etc etc.

 

[Four Strings]

2000 FPM descent. Alt to lose divide 2000 multiplied by ground speed in miles per minute.

26k to 10k. 420 knots GS

16k/2k multiplied by 7 = 56 miles. Usually add about 10 miles to that to allow for slowing to 250.

I always round to the higher even number. If I have to lose 17k of altitude I do the math in my head for 18k. 9*7=63.

300kts = 5 mpm
360 = 6 mpm
420 = 7
480 = 8
and so on

 

[h25b]

I simply use the "Force" ... But if your last name IS NOT Skywalker it might not work for you...

Now if I could just figure out a way to get my light sabre past the TSA I'll be in business...

 

[dojetdriver]

I put the little pink banana thingy in front of the fix and go back to reading the paper.

Dude, when I transitioned to the ERJ from an aircraft that had the banana/ VNAV thingy it was a shock. The ERJ doens't have one. I thought I was going to wash out of training right then and there.