Foreflight enroute fuel management

ipengineer

ipengineer

Pre-Flight
Joined
May 28, 2012
Messages
49
Location
Dallas, TX
Display Name
Display name:
ipengineer
I have been talking with my instructor about using foreflight for cross country. He had never seen it before we started flying together. I think I have him sold on it. The one thing that we are trying to figure out is how everyone is handling fuel management when using foreflight.

When we plan our flights out on paper we will set checkpoints every so often and make sure our actual time to that checkpoint matches our estimated time during flight planning. The idea he conveyed to me was that if the time is continuously over what we estimated we should be thinking about our fuel.

So my question is are you guys using foreflight enroute for fuel management and if so how are you doing so? I didnt see in the navlog where it has both ETA/ETE and ATA/ATE.

I am almost done with my PPL so I am definitely green but it seems to me it would be easier to say.. I have 3 hours of fuel onboard I am not going to fly a minute over 2. In my mind that reduces the workload in flight and lets you pay more attention to flying the plane.
 
I wouldn't over think it. Just be super conservative in your calculation. I am guessing you are flying a trainer, like a 172 or Cherokee. In my Cherokee, I used 10 gallons per hour (it always did better). I have never landed with less than an hour of fuel. The Cherokee holds 50 gallons, so I usually top it, if weight isn't an issue or plan a fuel stop if it is. For switching tanks, I had a kitchen timer velcroed to the panel and also a watch. I don't think FF will help much, other than give you an estimate on flight time. Again, buffer that to allow for maneuvering around the airports, vectoring by ATC and unexpected head winds.
 
You have the right approach. Before takeoff, establish a "wheels on ground" time and observe it. Be conservative.

Bob Gardner
 
I fly a C172 that has about a five hour range. I work on a three hour Max plan with full fuel, one, it is safe and won't run out of fuel. Two, my butt and bladder can only take it for about that long.

Now with that said, I use ForeFlight but I still do a quick sanity check calculation based on fuel burn at cruise and taxi take off allowance and make sure ForeFlight and I agree. Fuel is the one area I want to be extra sure I am right.
 
Set the fuel burn in Foreflight a little higher than actual.also you can input waypoints and check time and gallons used.the nav log seems to give you what you need.
 
I dont like FF fuel burn calculation. it only allows one burn rate and does not allow for takeoff, climb, and descent. i typically burn about 24gph on take off then when im set up for cruise climb its about 21-18gph depending on how high I climb because of leaning at higher altitudes. then my cruise is about 10gph and descent is about 6-8gph.

So because of this I use 15gph for the FF app. I figure that is an average for the typical flights i make.

I think it would be nice if it allowed a climb and descent rate to be put into the calculator.
 
foreflight isn't really set up to do ETA vs ATA because it's a live navlag that always has the most accurate ETA possible. Once you get to the waypoint you'll arrive at exactly the ETA because it's always being recalculated. But, so are your estimated ETAs at the rest of your trip. You just need to keep track of your fuel used on paper (or obviously with a totalizer if equipped) and check to make sure you still have enough to get to your destination.

With FF you have the advantage of accurate GS numbers so in that regard it's better than the crude "are we consistently arriving late" method.

Know what you started with and track it somehow, either on paper or on the scratchpad page do you have a decent idea of how much is left in the tanks and you'll be fine.

PS, this instructor had never heard of Foreflight before?
 
Last edited:
ipengineer said:
So my question is are you guys using foreflight enroute for fuel management and if so how are you doing so? I didnt see in the navlog where it has both ETA/ETE and ATA/ATE.
Click to expand...
As much as we sometimes like to think otherwise, ForeFlight (and its EFB cousins) don't do everything.

Assuming nothing in the on-board avionics to perform the function, I use another app to remind me to switch tanks in a low wing and, when time/fuel management is an issue, create timing waypoints and not the times just the way I did with paper (although also on my tablet)
 
I use FF for flight planning and have the profile for my plane set up to be a burn rate that is higher by at least 20% of my actual burn rate. I use that plus a set time I am not going to exceed in the air. I don't ever really trust the fuel level sending unit. I do however trust my fuel flow meter that I have worked to calibrate over time. It is great since it shows the actual GPH rate in real time. My Dynon D-180 uses this to calculate how much gas you have actually burned over time. It is very accurate, provided you just either hit the full tanks or how many gallons you added after fueling it up.

Carl
 
I set Foreflight fuel burn at 14 GPH on the 182, that's probably pretty close, block to block. I use 135 knot cruise speed and add a few minutes to the estimated enroute time when I file the flight plan.
 
Thanks everyone for the feedback! I will let my instructor know..

Ted, I think he has seen people using it before but never understood what it was.
 
I've been asking FF for pop-up timer ever since they came out . . .

Not only would it be helpful for fuel timing but also relevant to instrument approaches . . .
 
You must log in or register to reply here.
Back
Top