bio fuel works on jet engines, why not being used ?

Question

research and developement , cambridge

Answer 1

Bio fuel is currently alot more expensive and it is not as pure as the jet fuel that they are currently burning... if they started using bio fuel on jet engies they would have turbine problems that can cost millions to fix... Also, It hasnt proven itself yet... if it is anything like ethanol for cars, jets wont get the performance they want... meaning that jets wont burn as hot and more fuel will be burned per hour... not really an option at this point...

Answer 2

the fuel systems in cars can run 100% ethanol, for a little while anyway, before you spring a fuel leak and end up with a fire, unless the fuel system was designed for high ethanol. Most cars can run 10% ethanol and the risk of a leak is acceptable. At 15% ethanol, the risk of death and mayhem increases and in a litigious society, its not worth the risk. Car engines computers can handle 10% ethanol without re mapping the fuel injection system and changing out the fuel injectors which must be larger for high ethanol fuel. The mapping gets the air fuel ratio close, then the O2 sensor can fine tune the fuel injection rate to assure that the exhaust has enough O2 to allow for the destruction of CO, NOx and HC's in the exhaust. the O2 sensor can't make the fuel injectors to adjust for much more than 10% AND have the exhaust meet all pollution requirements.

Answer 3

mostly costs of making it. I know while working on B-52 bombers we had a fuel book that listed all the different fuels that can be used in the bomber. it listed alot of the JP fuels. then flipping more through I saw listings for diesel and kerosene and a few others I cant remember. we joked about that plane could probably run on water alone lol. but its amazing what types of fuels can run a jet engine. granted to use those 2 types of fuels on the bomber had to be a war time situation or in case of an emergency there was no primary fuel. but it can run on it if need be,

after all all jet fuel is a type of diesel fuel. seen guys dip their hands in it and light it on fire to light cigarettes. then put it out and never burn their hands as the fuel burns only on the top layer of the fuel.

Answer 4

The easiest way to answer this is reliability, and cost. If you want the reason it's not a reliable option and definitely not a cheap one, keep reading.

For ground operation, diesel, jet fuel, home heating oil and kerosene are all largely interchangeable with much change in performance.

Jet fuel is highly refined kerosene, which is refined in a fractionating distillation column. Kerosene is only one level above diesel fuel.

For operations within the nation, the preferred fuel for jet engines is Jet A, and for intercontinental operation, the preferred fuel is Jet A-1 because Jet A-1 has a lower jelling point than Jet A. Bernouli's principle taking effect, it's colder at higher atltitudes than lower altitudes, so figure 8 hours of flight at something above 36,000' and you could have fuel gelling in the tanks. Gelled fuel won't burn.

Currently, diesel engines are satisfactorily on unrefined, used fryer oil. Stick a mason jar full of oil from your fryer into the freezer and see what happens in only a few hours. Ponder what that would do to the several micron filters and injectors of a jet engine.

Another aspect is the water content. All kerosene based fuels contain a certain amount of water. Publication ATA 103, produced by the airlines, allows for up to 15/ppm of entrained water in jet fuel. Fuels derived from plant and animal oils have much higher water content, which will freeze. So if you get around the fuel gelling, you have to worry about the ice crystals plugging the fuel filters on any flight where the temperature of the fuel in the wing tanks could drop below water's freezing point.

Volume is another factor; a dedicated environmentalist could, in the early hours of a Saturday morning, hit up enough fast food places to get enough fryer oil to run a fryer oil converted Mercedes, Isuzu pickup, or Jeep Liberty for a week or two. The Lear 35 typically loads 500 or so gallons of fuel to fly from Dallas to Los Angeles. You'd have to hit a lot of fast food joints.

And the FAA certifications are tough to get around. Unless type certificated to operate in a manner that's not allowed by the FAR's requirements for the aircraft. You have to be either the military, to which the FAA doesn't apply, or label the aircraft as experimental, which prevents it from airline service to test it and do your testing well away from anyplace where it can fall on people.

So you'd have to chemically reduce the gelling qualities of vegetable and animal oils, chemically reduce the water content of the fuel, provide FAR, (Federal Aviation Regulation,) required redundancy for engine systems, then flight test for several years, then find and devollop an infrastructure to make it available.

I'll be surprised if jet aircraft convert to biofuels in my lifetime. It's a pain, it's expensive, and a lot more R&D needs to be done before it's going to be a viable option.

Answer 5

The Air Force is using bio jet fuel on many aircraft. They even have a refinery near one of their Mid-west bases. It, at the present is not being used in high performance fighters, yet. Why? For obvious reasons, you don't want to drop one of those multi-million dollars rigs in the name of economy. After it is proven you will see it in 747's and everything else.

Another reason is the God Almighty oil companies. Until they are regulated our oil situation will not change. They own Washington, DC.

Answer 6

Because USA too ignorant, because India too involved with their jolly plane rides, because China has not come up with a fine grade alternative fuel yet, because UK not interested unless all other parties cooperate too.

United Nations a must if man wants to avoid self destruct.

Answer 7

Because its not in the interest of the petrochemical companies to substitute their main stream product for a bio ethanol replacement.

Answer 8

On a personal level the way Id see it is ...... "Good Morning Ladies & Gentlemen we will be departing soon I hope you enjoy the flight, by the way today we'll be flyind at 35,000 feet and using pig manure for fuel..which by the way costs an extra 40$ per hour /per head for the trip so if we make it the cabin crew will be collecting your money as you disembark

Answer 9

Not with bio fuel, but already has alcohool (methanol) been used.

Answer 10

less power also need more to get where you want to go would have to do mods to be right to fuel nozzels and bigger tanks for passanger planes military would want the power so unlikly to go there.