This NASA designed ducted fan aircraft has a Chev LSx V8 mounted in the rear driving the ducted fan with a long shaft. Many have been there and done that and it did not work. The fan acts like a flywheel on a long stick. The stick fails in torsion. If you crash this airplane you are sure to be crushed as the 500 pound car V8 engine makes it's inevitable way to the exact point of impact. An LSx V8 is about the lightest duty car engine you can find while weighing 500 pounds. It is rated at 400 HP in the Corvette while the car needs only about 30 HP to cruise at 80 MPH. It has a cast iron crankshaft, cast pistons and powdered metal connecting rods. Here is a spec sheet from www.GMpowertrain.com.



In a real aircraft engine only the highest strength vacuum melted steels and forged pistons are used for these parts for very good reasons. Consequently there is a reason why car piston engines don't work in aircraft. Every year at OSH a new aircraft application of the Chev LSx V8 appears. The following year or so it is nowhere to be found. Chevy V8's last about 200 to 300 hours in aircraft use and then they self destruct in the hand grenade mode without warning. Here is what could happen if the moving parts of the engine are not designed for a 2000 hour fatique life at aircraft engine power levels.



You can limit a Chevy V8 to 200 HP but then you have an engine with a power to weight ratio of over 2 pounds per HP while a real aircraft engine or a Wankel rotary weighs one pound per HP or less. You can replace these parts with aircraft quality forged 4340 and 4130 parts and maybe get the TBO up to 1000 hours but then the Chevy engine cost as much or more than a real aircraft engine and still weighs 500 pounds. Orenda has been there, done that and went bankrupt after spending 30 million dollars.



This ridiculous NASA design will weigh 3900 pounds gross and get less than 8 MPG IMHO. A Cessna 182 gets 13 MPG at a higher cruise speed.

These particular NASA people don't have a clue when it comes to aircraft structural design and experimental aviation history. Dozens of ducted fan airplanes have been designed and built and they all have the same problem. They run into a aerodynamic drag wall around 140 MPH. The surface area and frontal area of the duct add to the drag. Here is a graphic from Kuchemann and Weber's book Aerodynamics of Propulsion.







Here are a few pictures of ducted fan airplanes.





The Long EZ is owned by Perry Mick. He removed the duct and added a gear box and went 20 Kts faster with the same fuel burn.



Here it is after the duct was removed. Here is a quote from Perry himself. "Actually my ducted fan experience is worse than you write. Best speed with the ducted fan was 135 knots at 5400 engine RPM. With the gearbox and prop I am now doing 165 knots at 6400 RPM, since I can turn the engine up a little more."

"I suppose ducted fans can be quiet, but mine was very noisy. There were many complaints. A friend heard me fly over when I was 12,000 feet over his house on a cross-country. With the prop and the very same engine install, no one hears me anymore. No more complaints. People say it sounds like any other airplane. Maybe I was pushing the tip speeds but that was an attempt to make it as large as possible, that was still only 38 inches in diameter."

Perry



Here are some unrealistic requirements for winning the money. Mark Moore told us at an SAE conference that some one flew over his house and made noise. Apparently he has hated general aviation aircraft ever since. According to Mark Moore and NASA this is what it is ALL about. "NOISE, NOISE, NOISE."



This is what it is going to take to win the noise competition.

Down load this file http://handle.dtic.mil/100.2/AD779773

Rename the file to a .pdf file after you down load it. There is a mistake on the web site.

This well illustrates how ridiculous these guys are and their stupid "competition".



NASA's justification for this draconian noise attitude is airports are being closed because of the noise. The noise issue is a false issue publicized and used by the housing developers that want the land to make more money. The proposed Torrance California airport closing was a classic example. If it had become a housing development there would be no open space in Torrance or miles around for that matter in a vast urban area. Wild foxes were living on the field among many other smaller animals and birds. Car Traffic, already in grid lock, would be drastically increased and the infrastructure such as sewers and water supply would have to be enlarged at the tax payers expense. Same for police and fire departments. Fortunately the FAA stepped in and showed the developers and city politicians that the land was deeded as an airport in perpetuity. No other use was possible.

Here are the real reasons general aviation use is static. One of the problem with general aviation today is the light aircraft are not fast enough to justify the cost, the hassle of getting to your airport, inspecting and maintaining your aircraft and not having free ground transportation at your destination.



Witness the wide spread interest in small four place single engine jet aircraft.

Half the pilots that learn to fly quit sooner rather than latter. We need to get light aircraft speeds up to 300 MPH or more and get the cost down. That is where the Mazda RX8 rotary engine comes into play.



These are the entry requirements to win the 2006 prize. If you exceed any of them you are automatically disqualified. Consequently the draconian NASA noise limit is purely arbitrary. If you don't meet this noise spec no matter how good your airplane is in other respects you are disqualified for the prize money.



Aircraft interior sound proofing materials are heavy and expensive. The most efficient sound proofing materials are made from thin lead sheet bonded to a thin layer of foam. Obviously sound proofing any airplane including airliners would add unacceptable cost and excess weight.

A 52 MPH stall speed implies a very light wing loading. Light wing loading aircraft are high drag due to excess surface area alone at the 200 MPH minimum cruise speeds people want to fly. A 52 MPH stall speed aircraft is a very expensive toy not suitable for serious alternative transportation. If it flies at 130 MPH you might as well drive if you are traveling less than 500 miles. A 30 Kt head wind will make it completely unacceptable.

This is what Brien Seeley (President of the CAFE Foundation) thinks the winning aircraft should look like.







Suddenly it is the beginning of the last century.



The only difference is Brien forgot to include the cabane strut bracing wires. His design will separate the people pod from the wing and tail assembly when encountering the first turbulence or cross wind landing. http://www.airfieldmodels.com/information_source/how_to_articles_for_model_builders/construction/cabanes/index.htm Modern airplanes look the way they do for very good structural reasons.

The fact of the matter is if they relaxed some of these draconian noise requirements many existing light aircraft could take all the prize money. As it is some existing light aircraft are taking some of the money without significant modifications.

The 2007 contest was meaningless if four people can show up with stock airplanes and win our tax money. A person did show up with a stock C172 and walked away with $25,000. Beats the heck out of a $100 hamburger. This is a real farce. The whole program ought to be scrapped. These people that competed in 2007 and won are laughing all the way to the bank :) I can't believe NASA and CAFE are this stupid.

Vantage Prize, $100,000: Vance Turner of Rescue, Calif., owner of a short-wing Pipistrel piloted by Michael Coates -

Noise Prize, $50,000: Dave and Diane Anders of Visalia, Calif., owners and pilots of an RV-4 aircraft -

Handling Qualities Prize, $25,000: John Rehn of Santa Rosa, Calif., owner of a Cessna 172, piloted by Jeff Stocks -

CAFE Efficiency Prize, $25,000: Vance Turner -

Short Runway Prize, $25,000: Vance Turner -

Top Speed, First Prize, $15,000: Dave and Diane Anders -

Top Speed, Second Prize, $10,000: Vance Turner-

This is not the first time NASA has wasted our tax money. Back a few years ago they granted Williams International 100 million dollars under the GAP program to develop a small efficient turbo fan engine. The likes of Burt Rutan no less was giving speeches at air shows on how this new engine would revolutionize the light aircraft industry with a fuel efficient jet aircraft comparable with a Cessna 172. The engine never saw the light of day and the tax payer never saw his money again.

http://www.nasa.gov/centers/glenn/about/fs01grc.html

http://www.grc.nasa.gov/WWW/AST/GAP/GAPnews.htm

Under the same program they granted Continental 10 million dollars to develop a diesel aircraft engine. This too failed to materialize. This prototype is all we have to show for our money. Diesel aircraft engines have been around since the early 1930's. They are not viable as aircraft engines for two reasons. The power to weight ratio is poor and the fact that as you extract more HP from a diesel engine up to its max rating the fuel consumption advantage is reduced. NASA keeps proposing designs that nobody wants to buy or merely fail as viable aircraft engines. Those that fail to learn from history are doomed to repeat it. A man needs to know why something failed in the past. Nothing to do with diesels has significantly changed.







This new NASA program is a gross waste of taxpayers money not to mention fuel. We should all write our representatives in Washington and have them cut off money to this crazy project. What we need is low cost tilt rotor high cruising speed VTOL or Vertical Take Off aircraft. The commercial version of the V22 Osprey is a good start. Many people own enough land so helicopter level noise would not be an issue.

At one time NASA was called NACA. They started in the early 1930's. They did a lot of practical aviation research in those years that was too expensive to be done by private companies. Our major problem today is the cost of fuel. I am not saying we are running out of oil as a lot of "environmentalist" are claiming. There is plenty of oil in the ground for the foreseeable future. It exist in various forms. Some is cheap to extract and other forms are more expensive such as tar sands or gasoline extracted from coal. Anybody passing Economics 101 knows the the price of something is a function of supply and demand. As the supply goes down the price goes up. The two never meet. There will always be oil or gasoline but at what price is the question. NASA should be working on turbo compounding light aircraft engines to reduce the fuel burn of general aviation aircraft engines and lower the cost of flying. They should also be focused on the improving the aircraft for general transportation needs such has higher speeds and more miles per gallon.