The RC industry has evolved significantly, and with the introduction of electric RC planes, gas-powered models didn’t keep their place as the only option available. Nowadays, RC enthusiasts have a large choice of planes and can pick the best option according to their preferences, so what powering systems are available for RC planes?
There are three principal options for powering an RC plane: electric, fuel, and solar power. The most common one is the electric system which uses LiPo, NiMH, or NiCd batteries. The fuel-powered system remains popular due to its performance. Solar power is used in high-endurance RC planes.
Given this diversity, choosing a new plane becomes a more complex decision. In this article, we will explore each type of powering system in detail and compare them for a better understanding of each one of them. Let’s dive into it!
How are Electric RC Planes Powered?
Not many years ago, electric RC planes were considered nothing more than toys. The batteries were huge, and their capacity was low, resulting in heavy RC planes with very limited flight time. Over the years, the technology used in electric planes has advanced, making electric planes a valid option for RC enthusiasts.
An electric-powered RC plane is powered primarily by a motor that draws energy from batteries. This power is used to turn the propeller to move the plane forward. The speed is controlled by an ESC (Electronic Speed Controller) which regulates the power flowing from the batteries to the motor.
In my opinion, building your own RC plane will help you understand those concepts more profoundly. It requires you to understand the role of each part so you can effectively assemble and operate the plane.
Since our article is about powering systems, I’ll try to write about batteries in greater depth, and we’ll talk about other parts in the next article.
There are three main types of batteries used in RC planes. The most common are LiPo (Lithium Polymer) batteries which are the most popular choice and the best in terms of efficiency. There are also the NiCd (Nickel Cadmium) batteries which are not used much nowadays due to the toxic Cadmium content, and the NiMH (Nickel–Metal Hydride) which were wildly used before the introduction of LiPos.
We can find other types of batteries such as Li-Ion (Lithium-Ion) and lead-acid batteries which are not very common in the field except for specific use.
Lithium Polymer Batteries (LiPo)
LiPos are the most widely used batteries in modern electric RC plane models and are my favorite as well. They are lightweight and carry a high amount of energy, which makes them support fast flying and the execution of air maneuvers.
The disadvantage of these batteries is that they require careful charging and discharging to prevent damage. Fast charging these batteries beyond their recommended charge rate can cause them to catch fire or explode, which is certainly not something I’d enjoy in my home. So, unless you are looking for some visual and sonic effects in your house, I recommend adhering to the manufacturer’s guidelines.
Nickel-Cadmium Batteries (NiCd)
NiCd batteries are one of the first types of rechargeable batteries produced. They are known for their durability and ability to deliver consistent power output. They can handle high discharge rates without losing capacity and can perform well across a broad temperature range.
However, these batteries contain cadmium which is a toxic metal. They are also prone to the “memory effect”. This phenomenon occurs when the batteries are recharged before being fully discharged, causing them to “remember” the reduced capacity and leading them to a diminished overall capacity.
Nickel-Metal Hybrid Batteries (NiMH)
Before introducing LiPo batteries, NiMH batteries were a leading choice in the RC planes industry. They offer a good balance between performance and cost.
NiMH batteries are less prone to damage from charging and discharging than LiPos, although they’re heavier and offer less energy density.
These batteries are similar to NiCd batteries but without the toxic cadmium, and exhibit a less pronounced memory effect.
The problem with these batteries is that they tend to have a higher self-discharge rate, which means they lose their charge more quickly when not in use compared to other types of batteries.
Here is a line graph showing the evolution of battery capacity (mAh) over the years for LiPo, NiCd, and NiMH batteries.
How are Fuel RC Planes Powered?
When we talk about fuel-powered RC planes, we are referring to all models powered by internal combustion (IC) engines. These engines are similar to those used in cars but scaled down to suit RC aviation needs. IC engines provide some of the best RC plane models, they’re capable of powering a wide range of aircraft, from smaller trainers to large-scale models.
The fuel used in RC planes varies with the engine type. The most common engines run on nitro fuel, but gasoline is also used, especially in larger RC models.
Nitro fuel, also known as glow or glow plug, is extensively used in RC plane models. It consists of methanol, which serves as a fuel base, nitromethane which provides additional power, and oil to lubricate the engine. The specific blend ratio of these components can vary depending on the engine type and the desired performance levels.
Gasoline is not as popular as glow, it’s primarily used in large models capable of holding bigger engines since gasoline engines offer a lower power/weight ratio than nitro engines. Gasoline offers an advantage in terms of cost because it’s much cheaper than nitro, but requires more maintenance.
| Feature | Gasoline Engines | Glow (Nitro) Engines |
|---|---|---|
| Fuel Cost | Lower cost per gallon, more fuel-efficient, cheaper to run. | Higher cost per gallon, less fuel-efficient, more expensive to run. |
| Maintenance | Generally requires less frequent maintenance. | May require more frequent cleaning and maintenance. |
| Ease of Use | Can be more complex to start and tune initially. | Easier to start and tune, especially for beginners. |
| Power Output | Typically offer higher torque and are better for larger planes. | Provide good power and are well-suited for a wide range of plane sizes. |
| Flight Duration | Longer flight times due to better fuel efficiency. | Shorter flight times due to higher consumption rates. |
| Noise and Vibration | Quieter with less vibration. | Louder with more vibration, which some enthusiasts find appealing for realism. |
| Environmental Impact | Emits exhaust gases, though considered cleaner than nitro engines. | Emits exhaust gases, with nitromethane contributing to stronger odors and potentially more pollutants. |
| Initial Setup and Cost | Higher initial cost for the engine and setup. | Lower initial cost for the engine and setup. |
| Operational Temperature | Operates cooler, which can be beneficial for longer flights. | Operates at higher temperatures, requiring careful management to avoid overheating. |
Fuel vs Electric: Choosing the Right RC Powering System for you
The debate between fuel and electric RC planes isn’t exactly new. Back in the day, if you were into RC planes, fuel-powered ones were your only choice. Today, electric RC planes can offer as much thrill as the fuel ones.
Really, deciding which one’s better comes down to what you like and what you’re looking for in your flying experience. As for me? I’m all about electric RC planes. They’re just cleaner to deal with, require less maintenance, and tend to be kinder on your wallet over time. Sure, they can’t stay up in the air as long as fuel planes before needing a recharge, but I’m okay with that. I’m not one to fly for ages without taking a breather anyway.
Below, you’ll find a table I’ve put together. It compares different features of both powering systems, hopefully making it a bit easier to figure out which one might be the best fit for you.
| Feature | Fuel-Powered RC Planes | Electric-Powered RC Planes |
|---|---|---|
| Flight Time | Longer flight times on a single tank. | Limited by battery capacity. |
| Flying Experience | Realistic experience with engine sounds. | Quieter operation, less immersive but more neighbor-friendly. |
| Maintenance | Requires regular maintenance and clean-up. | Simpler to maintain. |
| Operational Complexity | Harder to learn. | Easier to start and operate, especially for beginners. |
| Noise Level | Louder, with potential noise restrictions. | Much quieter, suitable for more locations. |
| Environmental Impact | Emits exhaust; not as environmentally friendly. | Cleaner operation with no direct emissions. |
| Power/Performance | High power-to-weight ratio for larger models. | Advances in technology improve performance, but may be limited for very large models. |
| Costs | Ongoing costs for fuel; potentially higher maintenance costs. | Initial higher cost for batteries and chargers; lower ongoing costs. |
| Ease of Use | More complex overall operation. | Plug-and-play convenience with minimal setup. |