Single lever control

[CTMI]

Not sure if everyone’s seen it, but Stock flight systems, who makes EMU systems for the 912is and now 915is teamed up with Rotax and M/T propeller to make a fully automatic CS prop.

Basically the EMU uses the CANbus system to use readings from the engine to adjust the pitch of the blades according to pre made and modifiable “maps”

On 912 the governing variable was MP but with the 915 its %throttle since it’s turboed. 

Long story short you just push the throttle forward and the system sets the pitch and everything else.

Seems pretty neat but at the same time there’s a lot going on that you can’t control. Thoughts? 

[FlyingMonkey]

I admit to not much knowledge of CS props, but it occurs to me that the computer has no idea what you are trying to accomplish, so how does it know where to set the prop?  For example, are you going to full power because you are taking off and need climb performance, or because you are in cruise and need more speed?  Those require different prop settings.  It seems like the computer would have to be tied into more than just the engine and prop to make good decisions, like maybe an AHARS and a GPS...  Or maybe the bit about the maps lets you select takeoff/landing versus cruise.  But then it's not really single control operation anymore.

[WmInce]

29 minutes ago, FlyingMonkey said:

. . . . but it occurs to me that the computer has no idea what you are trying to accomplish, so how does it know where to set the prop?  For example, are you going to full power because you are taking off and need climb performance, or because you are in cruise and need more speed?  Those require different prop settings.  It seems like the computer would have to be tied into more than just the engine and prop to make good decisions, like maybe an AHARS and a GPS...  Or maybe the bit about the maps lets you select takeoff/landing versus cruise.  But then it's not really single control operation anymore.

Concur.

My peference is total control of the pitch, so I can set it where I want.

[FlyingMonkey]

7 minutes ago, WmInce said:

Concur.

My peference is total control of the pitch, so I can set it where I want.

Some of the joy of flying is in operating the airplane successfully and well.  I don't need an Airbus-style setup with full fly-by-wire and one button on the panel marked "fly". 

This kind of system makes sense for some commercial operations, but not the kind of recreational flying I want to do, I think.  Sometimes I even wish my 912 had a mixture knob!

[WmInce]

30 minutes ago, FlyingMonkey said:

Some of the joy of flying is in operating the airplane successfully and well.  I don't need an Airbus-style setup with full fly-by-wire and one button on the panel marked "fly". 

This kind of system makes sense for some commercial operations, but not the kind of recreational flying I want to do, I think.  Sometimes I even wish my 912 had a mixture knob!

Last time I checked . . . the Airbus did not have a prop lever.

Sure wish my CT had one. Maybe then, I could catch up to you!

[WmInce]

1 hour ago, Roger Lee said:

The new constant speed prop setup on the 915 being measured and controlled by the computers is more efficient than a human and usually smarter than the human even if the human doesn't think so.

"The best safety device in any aircraft is a well trained pilot."

[CTMI]

Roger have you heard anything about this system’s implementation in the field? Or anything on the 915 in general? This engine seems quite veiled in secrecy. Hard to get a handle on even basics like fuel burn etc.

I called Michael stock in Germany to enquire about the sing lever control system; he said that the computer does 100s of checks a second and sets the prop based on all available data. He said that the “curve” which is essentially a complex quadratic equation/function of prop speed and throttle % can be changed/modified so as to be optimized for a given plane and mission. Unbelievable technology really....

A friend is considering putting two 915s on a Velocity V-twin. The numbers pencil out.