UNDERSTANDING THE NITRO RC HELICOPTERNitro RC helicopters are still popular and serious contenders with electric RC helis. Why... Because they are tough and can take a beating, they are the lowest cost option for a fuel powered bird, and they have proven themselves time and time again. The pros and cons of nitro RC helicopters are explained on the Best RC Helicopter Power page. The simple fact is without the model nitro engine (also called a glow engine), it is doubtful that RC airplanes and helicopters would have taken off – literally. These little engines produce so much power for their size and weight it is little surprise that nitro RC helicopters are still the number one choice for so many people. 
Let’s first clear something up when it comes to nitro RC helicopters, more specifically nitro engines in general. Many people confuse or call these gas RC helicopters – this is not correct. Gas RC helicopters use 2 cycle gasoline engines, similar to the ones used in small gas powered chain saws or gas leaf blowers. Nitro engines or glow engines are completely different. They use special fuel consisting of (methanol, nitro methane, and oil) and as the name "glow" suggests, they don’t use a spark plug - a glow plug is used. Lastly, nitro/glow engines run at much higher RPM's – usually in the 13,000 – 16,000 RPM range. In order to build and fly a nitro RC helicopter, you have to be very familiar with how nitro engines work. The following items are the main things to understand when operating a glow engine. I intend to build pages one of these days, months, or years going over all these topics - if I ever get some spare time. 
FOUR STROKE RC HELICOPTER NITRO ENGINES Most people will only use 2 stroke nitro engines in their helicopter because of the impressive power to weight ratio. There are a few 4 stroke nitro engines out there so you should at least know a bit about them. The 4 stroke heli nitro engine has been around for about 20 years now. They run at a lower RPM and thus produce less noise. It looked like these would become popular for R/C helicopter use, but the added weight, extra cost, and reduced power has kept them pretty much under the radar. There is nothing wrong with the 4-stroke nitro engine, the 2-stroke simply produces more power and doesn’t cost as much making it the preferred choice. UNIQUE REQUIREMENTS Now that you know all about nitro engines, let’s examine how they apply to nitro helicopters. The RC helicopter relies on its engine more than any other form of RC model. RC planes can glide in for a landing, RC cars and trucks simply coast to a stop and RC boats will continue to float if their engines quit. Helicopters on the other hand depend on engine power to stay in the air. Yes there are auto rotations , but when you are learning or if you are a pro hovering inverted a few inches off the ground – an engine flame out will pretty much ruin your day and lighten you wallet. This dependence on reliable power is key to understanding the unique ways nitro engine set ups in RC helicopters differ from any other RC model. There are other challenges that nitro engines in RC helicopters face such as getting adequate cooling and the many different ways of starting the nitro engine. What about the nitro fuel tank ? Simple right... This is a huge topic on its own, getting it wrong ensures helicopter flying and engine problems. Speaking of fuel, what about all that messy oil residue . As you can see the RC nitro helicopter is a fairly complex machine with some interesting quirks, however the advantages of nitro engines still outweigh the disadvantages for most people.
|
