Remote Control Jet Engines: How Model Turbines Work, Thrust and Costs
Remote control jet engines are miniature gas turbines that power large RC jets, helicopters and even boats. They burn kerosene or Jet-A mixed with oil, spin at roughly 100,000 to 245,000 rpm depending on size, and produce from about 20 N (4.5 lb) to over 220 N (about 50 lb) of thrust. An electronic control unit (ECU) handles start-up, fuel flow and safety. Turbines give real jet sound and performance, but they’re expensive and in many countries require training or certification to fly.
By Kyle HilsonUpdated: October 20264 min read
How a model turbine works
Air enters the front and is compressed by a centrifugal compressor. Fuel is sprayed into a combustion chamber and burned, heating the air. The hot gas spins a turbine wheel, which drives the compressor on the same shaft, and the remaining energy leaves through the nozzle as thrust. The ECU starts the engine with an electric starter, lights it (with gas or kerosene start), manages fuel during flight, and shuts it down safely if something goes wrong.
Types
| Type | Output | Used in |
|---|---|---|
| Turbojet | Thrust from exhaust | RC jets |
| Turboprop | Shaft power to a propeller | Scale turboprop planes |
| Turboshaft | Shaft power through a gearbox | Helicopters, some boats |
Shaft turbines for helicopters are covered in turbine RC helicopters.
How much thrust?
Small turbines produce around 20–40 N and suit sport jets of a few kilograms. Mid-size engines of 80–140 N power most large sport and scale jets. The largest model turbines exceed 220 N for very large jets. Pilots match thrust to the jet’s weight; a thrust-to-weight ratio near or above 1:1 gives lively performance. Composite jets designed for turbines are discussed in CARF-Models RC planes.
Costs
- The turbine itself is a major expense.
- Airframes for turbines are large and usually composite.
- Fuel systems, ECU batteries, retracts and brakes add more.
- Turbines need periodic servicing by the maker or an approved centre.
- Insurance and certification may be required.
Safety and rules
- Many countries and clubs require a turbine certificate or proof of competence.
- Carry a CO₂ fire extinguisher at every session.
- Keep people away from the exhaust during start-up and running.
- Store fuel in approved containers.
- Follow the ECU’s start and shutdown procedures exactly.
Building your own?
Some experienced engineers build model turbines from scratch, often based on published designs. It requires precise machining, balancing and heat-resistant materials, and it’s risky. For most pilots, a commercial engine with service support is the safe route.
Alternatives
Electric ducted fans give a jet look and simpler operation, and electric “turbine sound” systems add realism. For many pilots, an EDF jet is the first step before turbines.
How a start-up works
Starting a model turbine is a sequence controlled by the ECU. The starter motor spins the turbine, the igniter lights a small amount of gas or kerosene, the engine accelerates to idle as fuel flow increases, and the ECU checks temperatures and rpm at each step. If anything is out of range, it aborts and cools the engine. Pilots watch the readings on a ground display or telemetry before taxiing. Shutdown also follows a cooling procedure to protect the bearings.
Fuel system
Turbines need a clean fuel supply: a main tank, a header tank or bubble trap that prevents air reaching the pump, filters, and fuel lines resistant to kerosene. Air in the fuel line can cause flameouts, which is why careful fuel system design matters as much as the engine.
FAQ
How powerful are RC jet engines?
From about 20 N to over 220 N of thrust.
What fuel do they use?
Kerosene or Jet-A with turbine oil.
Do I need a licence?
Often a turbine certificate, depending on country and club.
Can I build one?
Possible for skilled engineers, but risky.
More on this topic: the complete RC Basics guide covers the basics behind this article.
About 20 years in RC. Mostly boats in the NAVIGA Mini Eco Expert class, with many self-made parts; also a King Motor Baja 5B, a home-built electric plane, home-built nitro planes he has flown, and an RC helicopter. More about SwellRC
