As long as internal combustion engines power our helicopters, we are going to need fuel in one form or the other. So what does this "precious liquid" do and how does it work?
 

We use Methanol, which belong to the chemical group called Alcohols. DON'T confuse this with what you buy at the 'Off-Licence'!! Methanol's structural formula is very simple - CH₃OH. Its very simplicity makes it so powerful, as putting it simply; it requires very little energy to break it up. So into our engine goes methanol and oxygen and with a little compression to heat things up a bit, out comes Carbon Dioxide, Carbon Monoxide, water and a lot of noise.

Now with all of this metal grinding, grating and jarring we need some form of lubrication!! Perhaps more importantly, the oil also helps to distribute and remove excess heat. This is why we adjust our engines to give out large amounts of 'insect repellent'. If yours doesn't have a good healthy amount of smoke coming from it, then you had better seriously think about re-adjusting it. Now the single biggest argument about oil is what to use. Most old hands will swear by Castor, but if they do, don't listen!! In an aeroplane it is acceptable as it is a very good lubricant, but Castor oil burns at too low a temperature to be of any use in a helicopter. Add this to the brown 'varnishing' and the covering of your mechanics in a slimy goo, and you will soon see why we discourage its use. E.D.L. is a synthetic oil developed by Model Technics in 1980 and is still under continuous development. Model Technics Duraglo fuel contains 9% E.D.L. mixed with 6% Castor and their Helimix contains only 15% E.D.L. We tend to use Synthetic oils, they don't burn up at the high temperatures in our engines so they can be set slightly leaner, which means more power. Synthetic oils also wipe off the mechanics very easily, and won't stain your engine and pipe.

The last thing to consider is Nitromethane or as we call it 'Nitro' - CH₃NO_2. Basically, the more nitro content, the more power, BUT you have to use it correctly. By this we mean putting large percentages through say a Webra engine will have detrimental effects, it may even kill it, but using low Nitro in an OS means you will have very little power as OS engines prefer it. So read your engines instructions and/or distributors recommendations.

There are many fuels available but choose carefully, make sure it has a least 18% and no more than 22% oil and has the right Nitro content for your engine. For a beginner to intermediate helicopter a fuel with either 5% to 10% Nitro is sufficient. For an expert pilot wanting to fly 3D then 15% up to even 30% Nitro will be required.

Tip - When using a colourless fuel such as Model Technics Helimix it is advisable to add some red fluorescent fuel dye to the fuel so that you can visibly see the fuel level in your helicopters tank.

Model helicopter fuel is a hazardous substance being highly inflammable and highly explosive. NEVER use fuel indoors or in places with open fires or sources of heat. Store fuel in a cool, dry and dark place out of reach of children. DO NOT dispose of empty fuel cans in fires. Model helicopter fuel is also poisonous. If swallowed you should induce vomiting and consult a Doctor. If fuel gets in your eyes rinse them thoroughly and consult a Doctor.

Turbine Fuel

Model jet turbine engines can be run on either standard Jet-A1 or Kerosene mixed with a suitable Turbine Oil or TCW-3 marine two stroke oil at a ratio of 40:1. As Jet-A1 and Turbine Oil are not the easiest of fuels to come by and are pretty nasty substances a suitable alternative is Parafin (Kerosene) which is available marketed as 'Low Odour Parasene' from B&Q Warehouse where a 1 gallon container cost around £4.99. A standard mixture of Propane and Butane gas is used to start model turbine engines and can be found in blowlamp and camping gas cylinders.

When using highly inflammable turbine fuels and gases a CO₂ fire extinguisher must be at hand at all times and smoking should not be allowed when fuels are being handled.