“Descent requires before waypoint” on foreflight?

TheGolfPilot

TheGolfPilot

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It doesn’t make any sense they have descent required to destination but don’t have descent required to next waypoint. There is even a place to put you altitude at the waypoint. I wonder why they don’t add this functionality.

Do any other programs do this?


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Garmin GNS (and I'm sure the rest of the garmin GPS) has that functionality.
 
EdFred said:
Garmin GNS (and I'm sure the rest of the garmin GPS) has that functionality.
Click to expand...
They will. The later units will let you input the altitude targets directly into the flight plan.

There are also apps such as Sporty's EFB (and a plain simple calculator) which will do the basic calculations.
 
You need to figure this in your head. For a normal 3 degree descent, allow 3 miles per thousand feet you need to lose...multiply your groundspeed times 5 to get the descent rate. Example.....you need to lose 3 thousand feet....that would be started 9 miles out. Next if you are going 150 knots, five times 150 is 750...750 feet per minute. If that rate is too much and you want to cut it in half, start your descent 18 miles out at 375 feet per minute. Problem solved...learn to figure in your head...do not always rely on a gadget.:)
 
Doug Reid said:
You need to figure this in your head. For a normal 3 degree descent, allow 3 miles per thousand feet you need to lose...multiply your groundspeed times 5 to get the descent rate. Example.....you need to lose 3 thousand feet....that would be started 9 miles out. Next if you are going 150 knots, five times 150 is 750...750 feet per minute. If that rate is too much and you want to cut it in half, start your descent 18 miles out at 375 feet per minute. Problem solved...learn to figure in your head...do not always rely on a gadget.:)
Click to expand...

Too much math for me... I just use the ticker on the ForeFlight tray
 
Doug Reid said:
You need to figure this in your head. For a normal 3 degree descent, allow 3 miles per thousand feet you need to lose...multiply your groundspeed times 5 to get the descent rate. Example.....you need to lose 3 thousand feet....that would be started 9 miles out. Next if you are going 150 knots, five times 150 is 750...750 feet per minute. If that rate is too much and you want to cut it in half, start your descent 18 miles out at 375 feet per minute. Problem solved...learn to figure in your head...do not always rely on a gadget.:)
Click to expand...

My head calculation is a bit simpler. Take target pattern altitude minus present altitude, that gives you altitude to lose. Say it's 7000ft. 7000ft divided by 500fpm gives 14min of decent. Really I just take altitude to be lost in thousands and double it, and that's your minutes. Mooney in full power decent at 500ft/min does about 180kts, or 3mi/min. So, 14min * 3mi/min says I need to start decent 42 miles from the airport. I usually add 10mi to the number (52mi in this case) and request decent at that time. Center or approach doesn't always give you the decent immediately.
 
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Unit74 said:
Too much math for me... I just use the ticker on the ForeFlight tray
Click to expand...

Really? This is too much math ? WOW !

I hope your ipad doesn’t die. I use descent to destination during a non precision approach as a cross check on final...it is a nice feature. But I figure standard descent from cruise to pattern in my head...it is good to keep your brain active.

Just remember 3 and 5...3 miles per 1000 feet and 5 times groundspeed.
 
I dont worry about distance to waypoint. Only time. Makes all the calculations simpler especially if you plan at 500fpm. We should all be able to multiply by 5 in our heads - or 2. Like Bill said. How many 1000s of feet do we need to lose? Double that and that's how many minutes out you need to descend. No need to overcomplicate it with GS.
 
Bill Jennings said:
My head calculation is a bit simpler. Take target pattern altitude minus present altitude, that gives you altitude to lose. Say it's 7000ft. 7000ft divided by 500fpm gives 14min of decent. Really I just take altitude to be lost in thousands and double it, and that's your minutes. Mooney in full power decent does about 180kts, or 3mi/min. So, 14min * 3mi/min says I need to start decent 42 miles from the airport. I usually add 10mi to the number (52mi in this case) and request decent at that time. Center or approach doesn't always give you the decent immediately.
Click to expand...

Your method is fine if you know how to use it. The point is to get your brain involved !:)
 
Doug Reid said:
Your method is fine if you know how to use it. The point is to get your brain involved !:)
Click to expand...

And really for my case and decent rate/speed, I just need to take altitude to be lost times 6, and I get my decent point. I just wanted to show that the math isn't hard, especially at a 500fpm decent rate.
 
Ya. I can do the math, but when there is a handful of them going into an airport that in LA with a jet that only has a 430 in it, it would be really nice to have the $200 a year flight calculator I carry around do that basic math for me. And it could keep doing the math for changing air speeds during the descent, it would be nice to have.

They already do this calculation to the destination, why can’t they implement it to the user defined altitude point at a waypoint?
If Garmin Pilot does this I may have to take a look a switching cause I would


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Anyone ever see the movie Wall-E ?

1000fpm - Multiply by 1.
500fpm - Multiply by 2.

Life is hard.
 
Doug Reid said:
Really? This is too much math ? WOW !

I hope your ipad doesn’t die. I use descent to destination during a non precision approach as a cross check on final...it is a nice feature. But I figure standard descent from cruise to pattern in my head...it is good to keep your brain active.

Just remember 3 and 5...3 miles per 1000 feet and 5 times groundspeed.
Click to expand...


Been flying with iPads for at least 5 years now. Can’t say that’s been a problem. And honestly, it’s really unimportant to begin with. If I’m VFR, my eyeballs will judge the decent. If I’m IFR, ATC till established and then the rest of the technology tells me what to do.

But thanks for trying to tell us how smart you think you are.
 
You are welcome ! :)

Bill Jennings and I will be performing here all week and drinks are half price on Thursday nite !
 
Bill Jennings said:
And really for my case and decent rate/speed, I just need to take altitude to be lost times 6, and I get my decent point. I just wanted to show that the math isn't hard, especially at a 500fpm decent rate.
Click to expand...
Hope you have a decent descent:)
 
There's usually a little dot on the magenta line. Start decent there.
 
EdFred said:
I dont worry about distance to waypoint. Only time. Makes all the calculations simpler especially if you plan at 500fpm. We should all be able to multiply by 5 in our heads - or 2. Like Bill said. How many 1000s of feet do we need to lose? Double that and that's how many minutes out you need to descend. No need to overcomplicate it with GS.
Click to expand...
That is the real answer.
Of course, it requires knowing how many minutes out your are, but I have at least 5 sources in my cockpit for that information.

If I'm at 7,000 ft and I need to descend to 1,000 feet, (6,000 ft descent), that will take me 12 minutes at 500 ft/min. I start descending slightly before 12 minutes out.
The only time I worry about descending to a waypoint is for the approach fixes in an IFR approach. Then I just descend to the assigned altitude and maintain.
 
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