Hi !

I'm a french pilot... In our country fuel containing nitro is very expansive (more than 50$ for CP30 for example). So, many people use fuel without nitro (Henseileit 3dnt user's for ex.) and they say their heli are as powerful as heli with cp 30%. I use nitro and I don't agree with them...Otherwise, what will be the purpose to put nitro in fuel ?? What do you think about this?

Thanx,
Thierry

Nitro =Power.

thanx for your (short) answer...

I think so

Thierry

i have heard that the nitro provides oxigen, so you can add more fuel, and get more power. Also makes the needle settings less sensitive. and allows you to run extra rich keeping the engine cooler, while still producing flyable power. when i was a kid many of us added Nitros oxide injection to our cars, would add over 100 HP to some of those hot rod engines, but i dont' think the nitro does quite that much for these heli engines. nitro is almost free here compaired to eruope so everyone here uses a lot of it.

The manufacturers should just try to develop lighter and more powerful gasoline engines. There should be some kind of additives developed to take full benefit of the energy density of gasoline.

Gasoline is a lot cheaper and convenient. Plus it doesn't have the nasty smelling smoke.

Nitrogen is usually a triple bonded substance where alcohol usually has a double bond. The triple bond is tightly held together consisting of 2 pi bonds and a sigma bond on their orbitals. When the bond breaks the energy holding the bond is released.

If you want more power you turn to splitting atoms. Nuclear fission. If you want even more power you combine heavy nuclei. Nuclear fusion. Fusion hasn't been harnessed yet, but probably will soon. Still not enough power? Start inventing an antimatter reactor.

I'll get to work on that!! [sm=idea.gif]

Salut Thierry,


I sympathized with your pain; we have the same problem in Switzerland and I think, that it's the same problem for the entire Europe, because we haven't the chance to have !QUOT!nitro productors!QUOT! like in Japan or USA.

I don't think that small % of nitro brings you a lot more power, but for sure it helped a little because of the supplementary oxygen. I think that the big advantage of nitro is to maintain the temperature of the engine out of danger and it also avoid you playing with your carburetor every time you go to the field. At least, it's what I noticed the most with my different % of nitro.

The nitro is also necessary with standard carburetors, but if you install a !QUOT!Loetterle!QUOT! carbi on your engine, you'll be able to fly with 0% of nitro and less % of oil for the same power. That's the case with the standard 3D NT engines. It's think that it's just a matter of needle quality for the mixture.

I know a pilot that flies with a Rappy50 and changed his needle lately to fly with 0% nitro and he assured me that the amount of power is the same as before, but his costs for fuel are a lot lower. Another pilot closer to me flies with a Novarossi engine with 0%nitro and never complained about power when he makes his amazing 3D flights. I don't think, that we really notice the difference, at least outside the competition world.

The team of Henseleit advices a Loeterle carburator, because they know that one problem of RC/Heli in Europe is the price of the fuel. The heli is conceived to allow all the 3d you can dream about in this configuration and you can even do a certain 3d at 1300RPM according to the specs.

I promise you, that no pilot of 3D NT are complaining about the power of their heli, at the contrary, I would say. They probably pay less per flight with their 90 engine, then with a 60 with nitro!

He you have the opportunity, just try one of those engines and make your on opinion in comparison with your engine and costs.

I have ran 5%, 10%, 15%, and 30% nitro in my Webra 91.

The 15% had noticeably more punch than the 5% and the 30% had more punch than the 15%. I settled on 15% since the engine felt the smoothest to me.

There is a definite difference between 5% and 30%!! More nitro = more punch!

Nitrus-oxide and nitromethane are two COMPLETELY DIFFERENT things spaceman spiff. Nitrus oxide is basically 95% Oxygen and 5% Nitrogen. Nitrus oxide injection works by simply introducing pure oxygen under pressure (1500PSI) with extra fuel to produce extra HP. More oxygen= better combustion, and therefore more power. For example engine 'a' makes 100HP at sea level...... at 5,000ft of elevation it makes 75HP. Thats because for every 1,000ft of elevation you lose 5% horsepower. Why? Because theres less OXYGEN. Oxygen makes fire burn. Nitrusoxide isnt in the LEAST bit explosive! BUT: if theres a fire, and you add oxygen, a small fire becomes HUGE. Hope that makes sence.

Nitromethane fuel with higher concentrations of 'nitromethane' 10% VS 30% VS 60% is what gives the increased extra power. Higher % of nitromethane=MORE POWER. Its just that simple.

Tailrotorblade: If they arent using nitromethane for their fuel, what type of 'fuel' are they using?!?!?!?!?!?!? Did I miss something here?!?!?!?!?!?!?!?! I havent heard of 2 stroke engines made specifically for nitromethane fuel, running on ANYTHING but......nitromethane~!!!!!

Hi Todd...

They just use oil and methanol and no nitro...

Thanks all for responding...

WOW! I had no idea that they would even run without nitro!....Have you had a chance to try some in a heli you have allready flown, to see the difference yourself yet tailrotoblade? So I inagine they are just mixxing upi their own stuff, huh? Id be interested to see how it runs/cost....

Well, I feel like I want to clarify some things about glow fuel before i suggest a solution to the nitro-problem.

Glow fuel i based on methanol with an addition of about 20 percent oil and usually an addition of 5-30 percent nitromethane.

In defense of spaceman spiff I must say that Nitrus-oxide and nitromethane may be two different things, but they do exactly the same thing, they add oxygen to the combustion chamber thus creating a bigger explosion which give more power to the engine.

This is why you need to have a richer mixture when you use more nitro otherwise the engine will run lean. Think of nitro almost like having air in the fuel...

The downside with nitromethane is the impact on the environment, thats probably why nitromatheane is more expensive in Europe, we probably have some sort of tax on it.
When nitromethane is combusted something called NOX gasses are part of the resulting products, these are poisonous and harm the environment.

OK, how do i get more power without using nitrometane? For example there are European and Russian made engines which are made to be used without nitro or with very little (5%) nitro in the fuel, and they still produce the same power. What's special about these engines?

Well, as I mentioned earlier, nitro adds oxygen to the combustion chamber which creates a bigger explosion. Another way to accomplish the same is to increase the compression in the combustion chamber.
This can be achieved on an engine that needs more nitro (IE OS) by using a thinner cylinder head gasket or by simply removing it. The next thing you need to do is remove the cylinder lining and increase (heighten) the exhaust port with about 1,5 mm on a 46-50 engine and about 2 mm on an 60 engine. These two modifications together is equivalent to about 20 percent nitro in the fuel.

There is one possible negative effect when you do this modification, if you increase the exhaust port to much it will have a negative effect on the idling characteristics, whereas addition of nitro in the fuel actually also improves the idling of the engine.

Observe that I take no responsibility if you do this modification on your engine, do it on your own risk, but if it is done properly it works.

/Mattias

There is a nice explanation of what nitromethane is and how it works at PowerMaster fuels' website:

FACTS ABOUT FUEL No. 3 - Nitromethane, the Mystery Ingredient?
http://www.powermasterfuels.com/facts3.htm

Everything is covered in here...

[8D]

Its simple Nitro is like cocane for your engine and in Europe costs about the same too.