Quiz: What You Don’t Know About Flights and Fuel
Photograph by David Nunuk, Visuals Unlimited/Corbis
You know that a jet can get you across the country or overseas fast, but how much do you know about the fuel needed to fly you to your destination? Take this quiz to see how much you know about aviation energy.
Quiz by Marianne Lavelle
How much fuel could the Wright brothers carry on their historic first flight, December 17, 1903?
- One and a half pints (700 milliliters)
- One and a half quarts (1.4 liters)
- One and a half gallons (6 liters)
- Five and a half gallons (21 liters)
The gasoline that fueled the Wright brothers’ historic flight was gravity-fed from a quart-and-a-half (1.4 liter) tank mounted on a strut below the upper wing.
What would be the typical fuel consumption of a Boeing 747 on a long flight?
- 5 miles per gallon (2 kilometers per liter)
- 15 miles per gallon (6.4 kilometers per liter)
- 5 gallons (19 liters) per mile
- 15 gallons (57 liters) per mile
According to Boeing, a 747-400 that flies 3,500 miles (5,630 km) and carries 126,000 pounds (56,700 kilograms) of fuel will consume an average of five gallons (19 liters) per mile.
In terms of seat-miles per gallon (that’s how far one seat—occupied or not—can travel on one gallon of jet fuel), what was the average fuel economy of U.S. carriers on international flights in 2010?
- 5 seat-miles per gallon
- 22 seat-miles per gallon
- 32 seat-miles per gallon
- 52 seat-miles per gallon
The average international flight achieved 52.1 seat-miles per gallon in fuel efficiency in 2010, marking a 121 percent improvement since 1960, according to the U.S. Bureau of Transportation Statistics.
In 2012, Alaska Airlines had the highest fuel economy of major U.S. air carriers, making a 30 percent reduction in emissions since 2004. The steps Alaska Air took to improve fuel economy included all of the following EXCEPT FOR:
- Use of a sophisticated global positioning system to aid aircraft in flying more direct routes
- Use of winglets, or turned-up extensions at the tips of the aircraft wings, to reduce aerodynamic drag
- Use of wide-body jets to transport more passengers per flight
- Use of procedures that help pilots shut down engines faster
Although wide-body jets can carry more passengers, they are heavier and require more fuel than smaller jets. Alaska air used GPS navigation, newer more efficient aircraft with winglets, and overhauled ground crew procedures to save fuel.
Which plane trip would result in greater carbon emissions per mile (or kilometer) traveled?
- New York to Washington, D.C.
- New York to Los Angeles
Short flights, like those from New York to Washington, D.C., produce much higher emissions per mile or kilometer flown than longer flights do, because a large share of emissions is produced at takeoff, regardless of the length of the flight.
How much of the oil consumed in the world each year is used in aviation?
- 6 percent
- 16 percent
- 36 percent
- 60 percent
World jet fuel consumption was 5.2 million barrels per day in 2010, or 6 percent of total oil consumption, the International Energy Agency says. Motor gasoline, by contrast, accounted for 26 percent of world oil consumption, while distillates like diesel fuel and heating oil made up 29 percent.
Jet fuel makes up about how large of a share of the U.S. government’s energy needs?
- 10 percent
- 20 percent
- 50 percent
- 60 percent
Jet fuel accounts for about half of the U.S. government’s energy needs. It accounts for a large share of military fuel, because it serves as a single battlefield fuel, powering tankers, generators, and weapons systems on the ground as well as jets.
What is the primary component of modern jet fuel?
- Liquid propane
- Diesel fuel
Modern jet fuel is primarily kerosene, the same fuel used in small home heaters.
What action did the European Union take at the start of 2012 regarding all flights in and out of the EU that has prompted threats of a trade war?
- Required that they pay for their carbon emissions
- Required that they use renewable jet fuel
- Required that they meet new fuel efficiency standards
- Required that they levy a fuel surcharge on every ticket
A new law requires that airlines flying in and out of Europe take part in the EU’s Emissions Trading Scheme, meaning they must pay for their carbon emissions, approximately 2 euros per passenger as of 2012.
When was "hydrotreated renewable jet fuel" approved for use in commercial flights?
The fuel-certifying body ASTM International approved hydrotreated renewable jet fuel in the summer of 2011. Over the following year, 15 airlines performed commercial passenger flights with blends of up to 50 percent fuel from used cooking oil, jatropha, camelina and algae.
In 2012, what was the main stumbling block to wide use of biofuels such as hydrotreated renewable jet fuel in commercial aviation?
- To use it requires expensive retrofitting of jet engines
- The biofuels are significantly more expensive than petroleum jet fuel, so demand is not triggered and high risk is seen for investments in production
- There are objections to using food crops for biofuel
- Aviation biofuel has less energy density than petroleum jet fuel, so the jet doesn’t go as far on the same volume
The main obstacles to greater use of biofuel in aviation are commercial, not technical. Hydrotreated renewable jet fuel, typically made from non-food crops, is a drop-in replacement, requiring no engine modifications. It actually has a high energy density, allowing aircraft to fly farther on less fuel. But it remains more expensive than petroleum jet fuel.
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