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fuel burn da40

Posted: Wed Feb 21, 2018 5:00 pm
by ben2k99
I understand fuel burn for the DA40 should be around 8-10gph cruising. Does anyone have an estimate for the fuel consumption per hour that might occur for typical training maneuvers? ie: touch and goes, flying in the pattern, training in slow flight, etc?

Thanks

Re: fuel burn da40

Posted: Wed Feb 21, 2018 5:46 pm
by TJS
I did a lot of circuits for my night rating. Finished IFR in June all in my DA40. I did not use much more than that.
There are as many very low power settings as high in the circuit. It seems to balance out to same as cruising if not less.

Tim

Re: fuel burn da40

Posted: Thu Feb 22, 2018 12:19 am
by gordsh
I have the extended range tanks on my XLS and a full tanks give me 3 days of circuits and training maneuvers going at it for 2 hours a day.

Re: fuel burn da40

Posted: Thu Feb 22, 2018 12:32 am
by CFIDave
Assume 8-9 gph in a flight training environment as you described.

Re: fuel burn da40

Posted: Thu Feb 22, 2018 1:55 am
by Ben2k99
Thanks guys. One more question: do you think installing a powerflow exhaust on an older DA40 would be worth the fuel savings alone?

Re: fuel burn da40

Posted: Thu Feb 22, 2018 2:09 pm
by CFIDave
Install it for the increased performance, not to save money. I doubt it would ever pay for itself in fuel savings.

Re: fuel burn da40

Posted: Thu Feb 22, 2018 2:57 pm
by Rick
+1 on Dave's comment. Even if you ignore the initial purchase and installation cost, additional labor for the annual ICA maintenance would eat up any fuel savings. But in my opinion the performance boost is worth it. I've owned 2 DA40's, one with and one without PF, and the difference is very noticeable.

Re: fuel burn da40

Posted: Fri Feb 23, 2018 9:41 am
by Sandy
Fuel flow depends on the horsepower (Hp) being generated, and Hp is directly related to engine RPM. As there is no reason to "speed" on your downwind leg, use the lowest RPM that you're comfortable with, and, certainly, no more than needed to maintain pattern altitude at a speed lower than your flap extension speed. Leaning on your downwind leg won't hurt, either.

Sandy

Re: fuel burn da40

Posted: Fri Feb 23, 2018 1:37 pm
by CFIDave
During flight training, teaching students to fly the traffic patterns is all about building muscle memory to learn *standard* actions and flows, all of which must take place in less than 5 minutes/circuit. IMHO, dropping the RPM even further or leaning the mixture on downwind just to save a tiny bit of fuel would only complicate that process. Leave the mixture full rich, bring RPM back to 2400, and upon reaching pattern altitude set manifold pressure to 19-20 inches to hold altitude on downwind.

Re: fuel burn da40

Posted: Fri Feb 23, 2018 1:57 pm
by Rich
The business of leaving full rich, in my experience, leads to pilots who have learned that using the mixture control is dangerous. When I was instructing I often ran into low-time pilots who were taught to never touch the mixture control. And where I did most of the instructing way back when, full rich was not appropriate for takeoff, especially in the summer months. AND using full rich mixture in the low-power phase more than necessary is more likely to treat you to lead buildup on the plugs.

The deal is you'll reduce power on downwind anyway. Just pull the mixture back 1/3 or so. I'm no longer in training, per se, but it is my practice to not enrich for full-stop landing at all. It stays where it was all the way to shutdown. The exception is a go-around, of course.