Gas powered RC Helicopter
Gas RC helicopters (also called "Gassers") are commonly confused with the much more popular . They are however completely different; or to be more precise, the engine is completely different.
RC gas helicopters themselves are more or less exactly the same as similar sized nitro, turbine, or large electric. Gas powered RC helicopters are fairly big with the smallest being roughly the same size as 90 size nitros or 600 to 700 size electrics.
Century RC's Radikal 20 Gasser seen below spins 600 to 660mm rotor blades, weighs in at about 4.5kg, and is powered by a 20cc two stroke gas/petrol engine.
These 2-stroke gas engines used in gas RC helicopters are very similar to all single cylinder two stroke gasoline engines, just like what you might find in your gas leaf blower or chain saw.
As far as fuel, they use regular gasoline/petrol mixed with a high quality racing two-cycle engine oil. The sizes of these two stroke engines are also similar to what you might find in a gas powered weed whacker or small chain saw. The most popular 2-stroke gasoline engines for model aircraft are usually in the 20cc-30cc range.
have some interesting differences over the garden tool variety. Click on that link to learn more about these engines and discover the advantages they have over nitro engines. When choosing your gas model engine, you will also be faced with what kind of to use.
Gas RC Helicopter Performance
Because gas powered RC helicopters are fairly large, and powered by rather heavy two stroke petrol engines, the power to weight ratio of Gassers is fairly low compared to that of nitro or electric. You won't find a gas powered heli for example performing the hard core 3D smacking you see the new electric stuff doing these days. That certainly doesn't mean you can't still throw them around, and for sport or light 3D, they are very nice fliers.
The big advantage with gassers is the flight times can be fairly long (up to 30 minutes with some of them), fuel costs are easily half to 1/3 that of nitro, and unlike electric, you don't have to cart a bunch of big expensive LiPo packs around for back to back flights. With a gas RC helicopter, you just land, refuel, and go flying again.
As seen below on Century RC's Radikal G30; gasser mechanics are not much different than nitro. Perhaps the biggest noticable difference is most gasser engines have side mounted carburetors allowing easier carb tuning access and the ability to fit an air filter if you wish.
A large gas RC helicopter is obviously not your best choice for your first RC heli because of the higher cost of the kit, complexities involved building it, and dangers involved when flying a large model. Gassers (due to the large reciprocating piston mass in the 2-stroke engines) are also vibration prone; so you have to understand how to deal with that on a model RC helicopter as well.
However, once you have mastered a nitro or larger electric helicopter, a gas powered RC helicopter makes a lot of sense for some folks.See also:
Align T-Rex 500E Super Combo Kit with Motor, ESC, 4 Servos, Gyro, and Carbon Fiber Blades
Hobby (HRP Distribution)
Double Horse 26" 3.5 Channel Outdoor Metal Gyro Remote Control Helicopter
Toy (GGI International)
Syma S111G 3.5 Channel RC Helicopter with Gyro
Hobby (Syma Toys Industrial, Co.)
PEAK SHOP Hisky HCP100S 6CH 2.4Ghz Dual Brushless Flybarless RC Helicopter BNF
MJX F645 F45 4ch LCD 2.4GHZ Large Single Blade Rc Helicopter (Colors may vary)