Modeling joy. Feel the heartbeat of early aviation.
Have you ever watched an engine running and wondered what exactly is happening inside — how the pistons move, how the valves open and close, how all those separate parts work together as one machine? 
The R-5 Aircraft Engine was created to make those mechanics visible.
Developed by the Kinner Airplane & Motor Corporation in the United States and certified in 1935, this five-cylinder radial engine powered trainer aircraft throughout the 1930s and World War II. 
Reliable, air-cooled, and instantly recognizable by its star-shaped layout, it helped prepare a generation of military and civilian pilots before they took the controls of larger, more powerful aircraft, earning its place as one of the mechanical heartbeats of early aviation.
Connect the USB-C cable, switch the model on, and that unmistakable rhythm comes to life.
Five pistons move through the correct firing sequence — 1-3-5-2-4 — while the valvetrain opens and closes in perfect synchronization above them. The propeller rotates smoothly as the entire mechanism settles into the steady rhythm radial engines are known for, bringing the spirit of early flight to your workbench.
Every element is visible and exposed by design: metal pushrods, compression springs, gear-driven valve timing, and a crankshaft that ties it all together — assembled by you, running in front of you, explained by nothing except the mechanics themselves.
The milled propeller also features a built-in safety release mechanism that disengages if it encounters resistance. It's a thoughtful detail that helps protect both the model and curious little hands, paws, or anything else that might wander a little too close while the engine is running.

R-5 Aircraft Engine features:
●    Correct 5-cylinder firing order: 1-3-5-2-4
●    Fully synchronized valvetrain with metal pushrods and compression springs
●    Milled propeller with safety release mechanism
●    Electric motor powered via USB-C
●    On/Off switch integrated into the base
●    Control board built into the stand