Fuel Economy

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8434
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Name: Marshall B
Aircraft Type: Cessna 140
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Fuel Economy

Post by 8434 »

Hi Folks,

I'm new to the forum, and really happy to have all the information available here.

I just purchased a 140 in Quebec and flew it home to BC. It was a great adventure, especially since I hadn't flown a 140 before and I only had 10 hours in a Luscombe for taildragger experience. I am very happy with the plane, it cruises nice and lands easily. I am looking forward to adding a few things to improve it now that it's home.

Along the way I kept track of hours, miles and fuel consumption. I thought someone might be curious just how economical the 140's are. I should mention it has the C90, a 52 inch pitch prop and it was loaded to 1350lbs most of the way. I broke the data into Canadian and American units for ease of comparison with vehicle fuel economy. The short story is: 24 hours of flying covering 2083 Statute Miles using 114.5 gallons of 100LL. The averages are 4.8 gal/hr 18.3 mi/gal. I looked up vehicle fuel economies and found the worst, a Toyota Tundra 4x4 would have been cheaper and more efficient. The long story below:
Fuel Economy.PNG
Fuel Economy.PNG (25.94 KiB) Viewed 6699 times
**Note** Cost/hour and mile are in Canadian loonies.
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Re: Fuel Economy

Post by 6863 »

Welcome here Marshall. you really did a lot of diligent work on your flight home. I might not have had the patience. One aspect difficult to quantify is the amount of C140 navigation the way the crow flies versus your Tundra 4X4 not driving in a straight line. I have always figured that flying my 120 vs driving the same trip in my Silverado 1500 is mostly a wash with the 120 having a slight edge. But then we don't justify 120/140 ownership on fuel economy do we.
John Kliewer

"Make things as simple as possible but no simpler." Albert Einstiein

"Wheels move the body. Wings move the soul."
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Re: Fuel Economy

Post by 6298 »

You would have gotten better mileage flying East. Welcome to the group, and enjoy your new airplane.
Randy Thompson A&P IA Pilot
Hold STC SA547EA for installation of O-200 engine in Cessna 120/140 and 140A"s
Overhaul small Continentals
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5806
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Re: Fuel Economy

Post by 5806 »

What RPM were you operating at and have you checked the accuracy of the tach?

Great job collecting data! I like data!
John
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6643
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Re: Fuel Economy

Post by 6643 »

6298 wrote: Thu Apr 25, 2019 1:01 pm You would have gotten better mileage flying East.
Yeah, but he would have had to fly clear across Siberia! ;)
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5115
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Name: Martin Tanguay
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Re: Fuel Economy

Post by 5115 »

Marshall,

Welcome to the forum. Jacques had told me he had just sold his plane and that the crazy new owner would fly it back across the country all the way to BC. :D :D
Joking aside, congratulations on your purchase. And you just did a trip that a lot of people are and will only dream of. Would be nice if you could post a drawing (map) with the path lines and airport stops you have done.
You also bought the only C140 I ever seen that has cowl flaps STC installed on. Great option for winter flying and help keep our engine and oil to the right temp.
Enjoy your C140!
Martin Tanguay
Intl Cessna 120-140 Association - Canadian rep
C140, C-FJAR, 1946, sn:9168, O-200, ragwings
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Re: Fuel Economy

Post by 8313 »

Great information Marshall, Thank you.
On our 120 we typically use 5 - 5.5 GPH for the WAG calculations. Of course when looking a the data, there are many factors that go into figuring it all out. Aircraft modifications, engine modifications, prop pitch, weight, leaning, flight profile, etc., etc. Thanks for providing the information it is good to see the data.
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8434
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Re: Fuel Economy

Post by 8434 »

I'm glad you guys enjoyed the data. I was trying to run around 2200 - 2300 RPM. I had lots of time set aside for the trip so getting anywhere fast wasn't required. I guess having a fuel/engine monitor might be the best way of actually determining performance since my data isn't compensated for weight and altitude.

Martin, Jacques was an excellent seller and I thoroughly appreciate him driving me around Lachute to make the sale happen. As for crazy, I definitely felt that way a few times prior to the trip. I have my wife to thank for telling me to quit whining and do it. As for the map, here is the SPOT locations:
Cross Country.PNG
Cross Country.PNG (272.82 KiB) Viewed 6522 times
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Re: Fuel Economy

Post by 5115 »

Thank you Marshall for sharing the map. Very impressive.
Keep on posting your flight experiences with your C140.
Martin Tanguay
Intl Cessna 120-140 Association - Canadian rep
C140, C-FJAR, 1946, sn:9168, O-200, ragwings
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Re: Fuel Economy

Post by 5115 »

Sent you a Private Message Marshall
Martin Tanguay
Intl Cessna 120-140 Association - Canadian rep
C140, C-FJAR, 1946, sn:9168, O-200, ragwings
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