# P3D v4Helicopter horizontal speed 'curve' (adjusting a curve? )

#### lionheart

Hey all,

Can one adjust the horizontal thrust on a helicopter to be low on the bottom, and then near the middle, perhaps even 2/3rds into the power/cyclical range, the horizontal thrust finally kicks in? It would be a very odd curve where it was very low until past the half way point, then would rocket upwards.

Is this possible?

What I want is a helo that flies very smooth and calm at low power, and at full power, I want this thing to act like a rocket.

I had done this many years ago with the Blade Runner Spinner, but that was, I think FS2002, maybe FS2004. I could get 200 knots out of her, detuned the 'flies crooked' effect, etc, etc. But it just wasnt polished enough. I want 'really fast', like 800 knots or faster, but to hover very very nicely. Can a helo do this? Can the turbine thrust be adjusted to be higher but with a curve in the middle?

#### Roy Holmes

Resource contributor
A helicopter’s horizontal thrust is a component of the lift from the rotor obtained by tilting the rotor disc with the cyclic control stick. The rotor still has to produce a vertical component equal to its weight to sustain horizontal flight. Lift comes from a rotating set of airfoil /blades. At any one moment one side of the rotor is advancing and other is retreating. The speed of the advancing side through the air is the sum of the true airspeed and the rotational velocity of the rotor measured at right angles to the blade axis. At some true airspeed that sum will be supersonic. On the other side there is a true airspeed where the retreating blade is going backwards at the same speed that the helicopter is moving forwards so it’s velocity relative to the airflow is zero. Those conditions represent the absolute speed limits on a helicopter and in either case the rotor lift would be zero in the stalled zero relative airflow and very low when the advancing blade tip goes supersonic. The rotor has not enough lift to keep the thing in the air and nothing left over for horizontal thrust.

Now, those are the facts of the situation. You could probably make something that looks like a helicopter, but flies like a jet in the sim in the same way as you can do a supersonic brick. Another fantasy airplane.
Roy

#### lionheart

Many thanks, guys.

#### As365

Hi, in heli model (B206) you may decrease a lot frontal and sides area and related drags, but adverse effects (strange accelerations, instabilities, tail fishing..) may come out at high speed. Also deceleration time will be affected.

And unluckly there isn't a parameter/scalar to increase only horizontal thrust component. You may adjust rotor Cl_min and _max, but you create a vertical rocket as well!

#### lionheart

Many thanks for that info, As365