Giants From Down Under

[towball]

	Quote: Originally Posted by notorious_benny
	That sounds like a great Idea towball!!! I would love to fly there. I lost my QQ foam Yak within 3 days. I have a thunder tigre expo 3d now, its good fun!

The QQ Yak is very delicate but a great hovering learning tool. We broke a couple of them before we gave them away and went back to the faithful Shocky.

I have tried the flatout reflection and it is a great plane to fly but again a little fragile, specially when you ditch em like I do. Not as brittle as the Tensor.

We have our monthly club indoor this Friday, so will throw a Shocky together before then..

Towball

[towball]

New video of the Xtreme Edge

http://www.flyinggiants.com/gallery/...ng_6-18-05.wmv

[notorious_benny]

Hey Towball are you just making shockies or are you buying them from somewhere?? if so where?

[morerevsm3]

	Quote: Originally Posted by 3W.
	Last year at albury its was a 35 degree day and marlin was flying his 100cc yak and glenno was flying his. Marlin had enough power to fly shedule but glenno didn't. The difference was 98 vs 89 octane. Glenno put 98 in his and seem to have enough power flying the same way. He recons there was more being the one flying it and it looked that way being a spectator to it all. This was a frigen hot day test which may not be as evident on cooler days. Dunno but this is what i saw hes fuel mighta been stale or had octane evaporate in hot bottle. Thinking about it he did have a big 10L bottle which was only 1/4 full. So is there a bladder bottle 10L you can buy thats static proof to keep fuel from loosing octane.

if Glenno's plane was tuned for optimum on a cool day, it would have been lean on such a hot day, unlikely to be an octane problem, as for optimax, and optimax extreme, they both are based on 95 octane fuel with aromatics to boost octane to 98, then ethanol to get to 100. An aromatic is something that evaporates, and if my memory serves correctly, optimax contains around 8% aromatics, while bp 98 and mobil synergy 8000 contain 3% aromatics, so can be stored with no ill effects much longer. also check the independant dyno results of different fuels here www.racefuels.com.au/dynoDetail.asp?id=59 and make up your own minds

[notorious_benny]

The hotter the day the richer the motor will run! Same as the higher the altitude the richer the motor will run. My motor splutters a little on hot summer days but runs clean and hard on a cool or cold day.

Hot air = thin air, this means you need to turn the needles in to reduce fuel and keep fuel air ratio the same. Thats why they lean carburetted light aircraft as they gain altitude to maintian as much power and efficiency as possible.

I personally dont like to lean my motors on a hot day as I would prefer to be a little rich and sacrafice power to be certain I am not going to overheat my motor.

[notorious_benny]

Carburetion
While the newest airplane engines do have fuel-injection systems that automatically adjust the fuel/air mixture entering the cylinders, older engines only have carbureters. This creates a problem, as the carbureter only atomizes the fuel to mix it with the air; it does not actually control the amount of fuel entering the mixture. So, an extra knob can be found inside the cockpit of airplanes with carbureted engines: the mixture knob. By adjusting this knob one can manually adjust the amount of fuel entering the mixture. This is very handy when flying higher than a few thousand feet, as the air density drops, decreasing the amount of air in the mixture. Thus, the mixture becomes too rich4 which decreases fuel efficiency and could cause the engine to quit if there is not enough air for the fuel to burn. Controlling the amount of fuel entering the cylinders allows for more efficient burning and safer operation.


http://www.bbc.co.uk/dna/h2g2/A650297

also read this I know it is a about full size aircraft but it relates.

http://philip.greenspun.com/flying/engine-management

[notorious_benny]

or

[RustyTumbles]

You are right ben,

The hotter the air the less oxygen it contains, therefore you need less fuel to maintain the correct air:fuel ratio. The same goes for higher altitudes, there is less oxygen up there and again you need less fuel. This is where the fuel metering devices on full size aircraft come into play. (air inlet pressure and temperature sensors) On a very hot day the power on full size aircraft engines will be less than that of a cold winters day. This is mainly turbo prop experience that I have, hower the same simple principals of internal combustion engines still applies. Hope this helps..

The added advantage of using 98 or higher octane fuel is that it burns cleaner and more efficeint than lower octane fuels. In some cases it will lower cylinder head temps and exhaust temps. However to get the most out of the fuel your engine needs to be tuned for it. i.e. your ignition may be advanced further before the engine will ping. I use 98 octane fuel in my V6 commodore and before I had the computer remapped the only advantage was increased mileage. Now I have a power gain because the ingition and fuel maps have been adjusted to allow the engine to make more power.

[flyboy]

Towball i had been told on weekend laverton has 3 mths before they have to move for housing projects there. It will be a great place for a comp can we ammenitys and things there ?

[3W.]

	Quote: Originally Posted by notorious_benny
	Carburetion While the newest airplane engines do have fuel-injection systems that automatically adjust the fuel/air mixture entering the cylinders, older engines only have carbureters. This creates a problem, as the carbureter only atomizes the fuel to mix it with the air; it does not actually control the amount of fuel entering the mixture. So, an extra knob can be found inside the cockpit of airplanes with carbureted engines: the mixture knob. By adjusting this knob one can manually adjust the amount of fuel entering the mixture. This is very handy when flying higher than a few thousand feet, as the air density drops, decreasing the amount of air in the mixture. Thus, the mixture becomes too rich4 which decreases fuel efficiency and could cause the engine to quit if there is not enough air for the fuel to burn. Controlling the amount of fuel entering the cylinders allows for more efficient burning and safer operation. http://www.bbc.co.uk/dna/h2g2/A650297 also read this I know it is a about full size aircraft but it relates. http://philip.greenspun.com/flying/engine-management

I have a 160 Fuel Injected OS in my little QQ yak. Out of the box it didn't run properly, for it was lean in ranges you couldn't adjust via radio. Knowing I had no one to cry to about this for service in Australia, I had a crack at solving problem myself without permanent modification. I ended up shimming the solenoid spring with plastic ring I made, and sanded it till it was right thickness which richened the problem ranges. The thing now runs fantastic, but the first run of the weekend the 15% oil mix clag from the weekend before causes havoc. Tried running it out of fuel weekend before but the oil seems to be still trapped and gathers. There is a small hole in injector as a breather which I shoot methanol from a s squirt gun into it. Doing this it starts and runs well for the whole weekend. In short, FI units in small methanol engines suck with high oil contents and only a 3 point range adjustment, u may as well use a good old mechanical needle. These bigger petrol planes maybe more suited to an FI, much lower oil contents, and a much bigger prop to have your hand next to while your tuning. I know these motors are set and forget but it would be nice to have a system that gave you 10 points of separate adjustments to tackle four stroking in lower ranges which seems to be hard to get rid of for most. I know some can but its a tricky skill for most who need to learn if you want to change one range its gonna affect another, which needs to be adjusted with the another needle. Anyone got some pics or links of a FI large gasser for planes in prototype form..

[3W.]

	Quote: Originally Posted by flyboy
	Towball i had been told on weekend laverton has 3 mths before they have to move for housing projects there. It will be a great place for a comp can we ammenitys and things there ?

There are houses there already going up..

[flyboy]

Tony i havent heard of any fi in model aircraft motors ie 3w or da maybee a large zdz or somthing but dont know of any. When i competed at Albury about a year ago it was the first time Bogan come out to compete in imac the weather was extreemly hot and everyones motors were stopping paris mine richo just to name a few we had to richen our mixtures to stop them from stopping.