Hypermiling Plane Gets 45 MPG at 207 MPH-Capable of 100 MPG!

[MitchJi]

Hi,

http://www.treehugger.com/files/200...ficient-plane-klaus-savier-45-mpg-207-mph.php

Hypermiling Plane Gets 45 MPG at 207 MPH, Capable of 100 MPG (That's Better Than Most Cars!)

With 2 People on Board (Unlike Photo Above)
Klaus Savier likes to have his cake and eat it too. Usually with airplanes, speed and efficiency are a tradeoff. You go slower and burn less fuel, or you go faster and burn more fuel (all else being equal). This is why it is impressive that Mr. Savier won this year's Fuelventure 400 in his modified VariEze (originally designed by the famous Burt Rutan) by getting 45 MPG at 207 MPH, and this with two people on board (and for those wondering, there were no massive tailwinds or anything of the sort).

Savier has altered his Vari-EZ and its Continental 0-200 engine by adding computerized fuel injection and ignition systems of his own design. He typically flies at 190 KTAS while getting a Prius-like 50 miles per gallon. If he slows to extend range, Savier's mileage approaches 100 miles per gallon.

Although his Vari-EZ carries just 30 gallons of fuel, Savier has flown it nonstop to Oshkosh, Wis., (1,522 nm) and Panama City, Fla., (1,700 nm).

To improve the flight efficiency of the GA fleet, Savier says magnetos need to be replaced, once and for all, with electronic ignitions, and engines need the kinds of precise fuel injection that allows his Continental to run an almost incomprehensible 300 degrees lean of peak. In fact, Savier says his engine runs so lean, and so cool, that he has trouble keeping cylinder heads and oil temperatures warm enough at altitude--even though his engine has no oil cooler.

Savier is not a newcomer to the field. He has flown his Vari-EZ "about 4,500 hours during 20-plus years of ownership" and during that time he has collected "mountains of data." He claims that switching to electronic ignition and computerized fuel injection would improve the GA fleet's flight efficiency 20% without any airframe modifications.

Time to modernize those engines!

 

[jag]

Burt Rutan's designs are fantastic. Some elements that make them very efficient are:

Overall minimized frontal area and drag coefficient of all surfaces.
Canard wing configuration gives lift from both wings. (Unlike a conventional plane where the rear wing pushes down)
Pusher motor in the back is more efficient than motor in the front.

I wonder what the efficiency of the original and modified as in the articel above Continental O-200 motor is. This is usually measured in grams of fuel per kWh produced (and varies by load, but airplanes unlike cars are usually run near the peak efficiency of the motor).
Good Diesel engines are in the range of 200g/kWh. Gas engines more typically about 270-300g/kWh.

For Rutan's around the world plane Voyager, Continental designed a watercooled boxer gas engine with higher efficiency than the typical aircooled motors used in airplanes. Voyager's motor also had an efficiency of about 200g/kWh -- a notable and needed improvement to get around the world with a reasonable amount of fuel. Carrying the weight of the fuel is a challenge for a long distance flight like that.

 

[spinningmagnets]

Turboprops are slower than pure jets, but The Piaggio Avanti and the Beechcraft Starship both made some unusual design choices for the sake of increased fuel efficiency. They both had the most modern design resources available, and the trends are noticable.

 

[jag]

Sadly the Beech Starship went the same way as GM's EV1. The new owner of Beech didn't want to be responsible for the support of an unusual aircraft during its lifespan so most existing Starships were repossessed and junked.

The Starship is also essentially a Burt Rutan design. His engineering company, Scaled Composites got to develop and build the prototype, which they did at record speed. However then it took Beech a long time to overcome a lot of practical problems in going from a prototype to a certifiable passenger aircraft.

As you can tell Burt Rutan is high up on my personal top list of designers/engineers. Ian Farrier of F-boats (trimarans) fame and Ken Salisbury (robotics) are also on the list. I'm curious to see if there similarly will be EV designer(s) who stand out above others. I think there are some very talented individuals on this list. Burt started by building his first plane in the garage, then offering amateur build plans for his canard aircraft mini-viggen, vari-eze and long-eze to home builders, and scraping by though this and the odd consulting/prototype job for a good 30 years before making national headlines with spaceship one.
http://en.wikipedia.org/wiki/Burt_Rutan

 

[bigmoose]

It's been known since the early 1970's that there is about 14% of improved BSFC (Brake Specific Fuel Consumption, ie lb fuel/hp hour) lurking near the lean ignition limit somewhere around 22/1 ish air/fuel ratio. The problem is the NOx. Because of the three way catalysts need to dither on each side of stoichiometric, to control THC/CO and NOx, we have lost around 10% in gas mileage from the get-go. Ask liveforphyiscs about the lean burn Honda's of the 80's and early 90's. They were spectacular. For 4 years I drove a 1997 Honda lean burn HX Civic with 200,000 miles on it, that regularly got 45mpg traveling the interstate to vendors. I still tip my hat to this gents aircraft efficiency!

 

[dogman dan]

Can't wait for Rutans latest creation to start flying from the new spaceport. I should be able to see em launch from my backyard if the weather is right.