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Post by jetcat3 on Jun 3, 2016 0:29:43 GMT
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Post by mackattack on Jun 5, 2016 0:57:44 GMT
Thanks for posting this - really interesting stuff and shows how efficient these airplanes really are. Even when we push these engines a bit, the numbers are still good!
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Post by Cluemeister on Jun 5, 2016 1:50:08 GMT
What's amazing is how much fuel is consumed for the last few knots of airspeed. See the attached fuel consumption chart for the turbo. To go from 93 knots to 120 knots, at sea level the fuel consumption goes from 3.3 to 6.9 gph!  |
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Post by MarkGregor on Jun 5, 2016 13:42:51 GMT
Over the years I have determined it is best to use these numbers conservatively as a guide only. There are so many variables that can affect this and running out of fuel is a main cause of accidents. Pilots sometimes ask how you can run out of fuel? Obviously it happens easier than we think because it happens too often.
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Post by geobuff on Jun 23, 2016 14:36:47 GMT
Prop Pitch has a strong effect on "mileage". See the Prop Pitch section in Hanger Talk. You may get lower fuel burn but not necessarily better mileage. Having prop pitched for 5650 RPM at WOT (wide open throttle in level flight) is the best of all worlds.
And yes Mark, WATCH OUT. Headwinds can kill you. When I came to Mankato for my Beringer wheels a couple months ago, I averaged 20 MPG because I fought headwinds the whole way up. In 1200 miles I stopped twice for gas and arrived with minimal reserve. When I returned to Florida, I had 50 mile per hour tailwinds and averaged 35+ MPG. I stopped once for gas and arrived with ample reserve.
I go by "hours in the air". I always stop for fuel every 4 hours, PERIOD. I use 5 GPH as my guide (even though I get a little better fuel burn). In 4 hours, I still have 8 gallons (minimum) remaining, a nice cushion for any emergency. NEVER go by miles traveled. NEVER say "I think....." Go by conservative guidelines and don't bend the rules. You will live longer.
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Post by geobuff on Jun 23, 2016 14:39:23 GMT
Prop Pitch has a strong effect on "mileage". See the Prop Pitch section in Hanger Talk. You may get lower fuel burn but not necessarily better mileage. Having prop pitched for 5650 RPM at WOT (wide open throttle in level flight) is the best of all worlds.
And yes Mark, WATCH OUT. Headwinds can kill you. When I came to Mankato for my Beringer wheels a couple months ago, I averaged 20 MPG because I fought headwinds the whole way up. In 1200 miles I stopped twice for gas and arrived with minimal reserve. When I returned to Florida, I had 50 mile per hour tailwinds and averaged 35+ MPG. I stopped once for gas and arrived with ample reserve.
I go by "hours in the air". I always stop for fuel every 4 hours, PERIOD. I use 5 GPH as my guide (even though I get a little better fuel burn). In 4 hours, I still have 8 gallons (minimum) remaining, a nice cushion for any emergency. NEVER go by miles traveled. NEVER say "I think....." Go by conservative guidelines and don't bend the rules. You will live longer.
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Post by geobuff on Jun 23, 2016 14:55:59 GMT
What's amazing is how much fuel is consumed for the last few knots of airspeed. See the attached fuel consumption chart for the turbo. To go from 93 knots to 120 knots, at sea level the fuel consumption goes from 3.3 to 6.9 gph! GREG: Do you have flow transducers and can you measure GPH? Something in that chart doesn't look right. First of all, they should list the prop and the pitch. They do not. Second it says 0 pressure altitude. You cannot fly on the ground without hitting cell towers. I would like to see you (or JetCat3) create your own calibrated chart. I have done this for my Astore 912_is, but I did not write down the GPH at all settings, even though i know what they are. At 5400 ROM, burn is 4.8 at sea level, gradually decreasing to 4.0 at 9500 feet. At lower RPM's, the burn is proportionally less. BUT mileage is a slightly different story. My DYNON also records 'mileage' which is a function of winds and is a relatively useless statistic for calibration. Mileage can help you stay out of trouble if you know your remaining fuel and the distance to somewhere. If you double click on the chart, it will get bigger so you can actually read it.  |
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Post by jetcat3 on Jul 12, 2016 13:49:05 GMT
Just ran Jim's numbers. 110 KNOTS true at 3.7 GPH. 110/22.2=4.95! Dang, that's pretty impressive. Obviously there a lot of variables I'm not accounting for here. I do wish there was a P2008 with the transducers and a prop pitch comparable so we could actually get a real measure of the fuel flow of the 914. Pretty amazing little airplanes indeed!
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Post by Flocker on Jul 15, 2016 18:02:35 GMT
Topped off with MOGAS this morning and turned on the endurance rings. Solid line is distance to empty. Dashed line is distance to a one hour reserve. Apparently I could have made it to Havana from Atlanta. 
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