What kind of fuel economy is achieved by small private airplanes?
Posted by admin in Finance Friday, 4 November 2011 16:44 5 Comments
When I say “small” airplanes, I’m talking about those owned by individuals for recreation, personal transportation, etc.
I really have NO idea what kind of fuel economy small planes get. If the answer varies widely based on model, feel free to give a specific example of model and fuel economy.
You will need to narrow down the question further to get a proper answer.
There are different types of airline fuel, more commonly classed as aviation fuel with grades and mixture. Engine size, plane weight, cargo weight, flying height and wing spans all add to the equation of how long a plane stays in the air.
Generally you will ask how many hours a plane can stay up with a certain amount of fuel. And give limits. Some of your answers can be googled if you ask the question correctly.
Small aircraft use a lot more fuel than cars. A tiny private airplane configured to fly as economically as possible still will not get better than around 15 mpg, and other aircraft and other configurations will get even worse mileage, around 8 mpg, for example. Since these aircraft can’t hold any more people than a car, this is pretty poor economy.
The extra fuel is required to overcome air resistance (airplanes fly faster than cars drive, and the power required to compensate for air resistance increases very rapidly with speed) and to provide lift to keep the aircraft in the air. It’s extremely difficult to make a small aircraft as economical as a car in light of these requirements. However, large aircraft that can carry many people at once can be much more fuel-efficient, thanks to economies of scale.
It should be kept in mind that, in exchange for higher fuel consumption, you get where you are going a lot faster. Fuel = speed.
About the best a small plane can do is a fuel burn rate of 5 1/2 gallons per hour cruising at about 60 to 70 miles per hour. Some do better some do worse but this is pretty normal for a small lightweight plane.
Our Twin Comanche burns about 12-14 gal/hr at low cruse settings at 7500-8500feet (altitude matters here), that results in about 180-185 miles of travel therefore its getting between 12.8 to 15 miles per gallon. (Had to do the math cause never have checked that before.) Truth is if cars traveled that fast, they would do worse than that considering how many cars get 18-20mpg at 60mph!
The newer LSA (light sports aircraft) like the Cessna SkyCatcher burns around 5 gph (from the spec sheet it really is probably closer to 7) at 118kts (135mph) should therefore deliver about 27mpg! Note: even at 7gph that would be about 20mpg.
Hope that helps.. The Twin Com. numbers are from a known aircraft and known numbers, the SkyCatcher is from a “specification” which may or may not be actual and usually isn’t!
a C-172 RG at 4000 pressure alt at 0 degrees at 24″ MFP and 2400 RPM burns about 9gph.
TAS is 116 knotts, so with a 0 windspeed (not taking into account for ground speed), gets about 12.8 mpg. This is at cruise power, mixutre leaned out.
Actual MPG over the course of trip would be much less, as run ups burn about .8 gallons (allowed per performance tables) and about 1.3 gallons to climb from sea level to 4000pa.
So a typical trip of 100miles, you would average about 9 gallons for cruise, .8 gallons for run up, and 1.3 gallons for climb, and about 1 gallon for landing, and taxing in (they dont provide this info in performance sheets) so Average MPG on a typcial trip would be 8.3 mpg, but you dont have to deal with the I275/696 interchange at 5pm on a friday..