The main developer of HELI-X holds a PhD in applied mathematics and is an expert in computational fluid dynamics. He worked successfully on many projects in aerodynamics. He is not only pilot of R/C helicopters and planes but also a private pilot of airplanes. He says: « Of course there are many books and publications on helicopter aerodynamics and flight simulation available. However, the aerodynamics described in these publications mainly deal with the stationary situation and are in a Reynolds number regime which is different to what is of interest for R/C helicopters and planes. But even more important, the flight dynamics of R/C helicopters is much more complex than that of the full size helicopters, so that particular models had to be built. In fact, the physics engine of HELI-X is written from scratch. Another important feature of HELI-X is that also the flow outside of the helicopters or planes is modelled which e.g. enables a realistic behavior in auto rotations or the spin up of the rotors. “

Besides others, the following effects are modelled in HELI-X:

  • Transitional lift
  • Stall
  • Ground Effect
  • Dynamic Stall
  • Vortex Ring State
  • Boundary layer separation at the Blades
  • Paddle dynamics
  • Rotor head stiffness
  • Nick/roll coupling
  • realistic stall behavior on wings and stabilizers
  • hysteresis effects for the lift
  • induced air resistance
  • flaps and airbrakes