Cross Country planning question

[BoDEAN]

How many of you have your students list a Top Of Climb and Top Of Descent checkpoint on their cross countires?

My policy at my new job requires a T.O.D, which is something new to me (never had a student calculate that in the past....)

 

[minitour]

...exactly how do you determine descent fuel burn? Am I looking in the wrong part of the POH? I'm able to find climb and cruise but not descent...

-mini

 

[cessna_driver2]

...exactly how do you determine descent fuel burn? Am I looking in the wrong part of the POH? I'm able to find climb and cruise but not descent...

-mini

Some of the newer piper pim's had speed, distance, & fuel burn to decend. I've only come across them in some of the new pim's.

I used it for a 00 arrow.

 

[Mr. Irrelevant]

I teach it to all of my students. It's not really necessary but it helps those students who just wouldn't start a descent from 5500 AGL until they were 3 miles out. Makes them think a little bit more. I doubt any students ever use TOC again if they don't go on to get a commercial.

Mr. I.

 

[flyer172r]

Never had it taught to me in a piston airplane, never taught it to any of my students.

 

[groundpointsix]

I wasn't taught it, but really wish I had been. It's much less work to do it on the ground, ahead of time, than to be trying to figure it out while you fly, look for traffic, pick up atis, pick your nose, etc. Workload is even higher when you don't have some means of precisely measuring distance and groundspeed. (I didn't say it was hard, just that it's a higher workload before any of the anti GPS purists flame me) Besides, it just prepares the student for what they're going to have to do anyways when they get into higher performance airplanes. That being said, I still don't do it myself, but that's more because the airplanes i fly are generally equipped with a GPS and I have the experience now to do it on the fly anyhow.

 

[midlifeflyer]

...exactly how do you determine descent fuel burn? Am I looking in the wrong part of the POH? I'm able to find climb and cruise but not descent...

If you figure out your power setting for descent, look at the cruise chart and you'll get a ballpark figure for the percent power that setting used as the associated fuel burn.

Not that precise, but neither are the climb numbers in most single-engine manuals.

As to Bo's original question, I don't worry too much about that TOC. But I do ask my students to calculate how far out they will need to start descending in order to have a comfortable 500 FPM descent from cruise to the pattern, and to choose a nearby landmark.

 

[midlifeflyer]

(a simple one) i.e. 360kts g/s = 6 miles per minute... from 25,000 down to 1000' pattern elev. @ 2000 fpm = 12 minutes... so 12 X 6 = 72 miles out to start your descent... it's simple (hope I didn't fuk up the math!)

There's no reason for a student NOT to compute this

There isn't, but I really want to see that 200 FPM 360 KT descent in a single engine piston trainer.

 

[PropsForward]

Rule of thumb we us is Altitude divided by two = miles out to start the descent.


Example.

6000 feet

half of that is 3000, drop the as two digits.

30 miles.

Start you descent at 30 miles at about 500fpm and it works out nice.

 

[rumpletumbler]

Rule of thumb we us is Altitude divided by two = miles out to start the descent.


Example.

6000 feet

half of that is 3000, drop the as two digits.

30 miles.

Start you descent at 30 miles at about 500fpm and it works out nice.

haha...in what?? Lear maybe? 90kts groundspeed hmmmm I lose my 3000 ft in 6 minutes and I'm still 21 miles out.