Hey guys, with release of MFS2020 gonna start flying GA flights, that brings up a lot if stuff I dont know. I have seen that on take off and landing pilots often move Torque lever but I never understand why. Do you guys have any video or smth to explain why and when I should do so? 
 

thanks

Welcome to the club. Simming is a great way to learn a lot of interesting stuff. Simply put : 

An aircraft engine needs, like a car, a mixture of fuel and air. Contrary to a car, it runs at a wide range of altitudes and the mixture needs to be adapted to the air density at the altitude you are flying.

Most piston engine aircraft have a cockpit lever to enrich or lean the mixture during the whole flight. It is a progressive lever from full rich to full lean. You look for the proper mixture by ear (does the engine purr at it should or cough) or monitoring a temp gauge.

Turboprops have an automatic barometric  pressure control built-in in the engine and no such lever in the cockpit. They have however a lever to start or cut the fuel injection. This is what, I think, you are refering to.

Torque is a rotation force, something else,  and has no specific lever . You control its effect by other means. 

 

Edited August 10, 20205 yr by Dominique_K

27 minutes ago, Dominique_K said:

Welcome to the club. Simming is a great way to learn a lot of interesting stuff. Simply put : 

An aircraft engine needs, like a car, a mixture of fuel and air. Contrary to a car, it runs at a wide range of altitudes and the mixture needs to be adapted to the air density at the altitude you are flying.

Most piston engine aircraft have a cockpit lever to enrich or lean the mixture during the whole flight. It is a progressive lever from full rich to full lean. You look for the proper mixture by ear (does the engine purr at it should or cough) or monitoring a temp gauge.

Turboprops have an automatic barometric  pressure control built-in in the engine and no such lever in the cockpit. They have however a lever to start or cut the fuel injection. This is what, I think, you are refering to.

Torque is a rotation force, something else,  and has no specific lever . You control its effect by other means. 

 

Got it, thanks for welcome. turns out I was reffering to RPM lever. As you can see in this video at 6:45 he reduces RPM but not thrust, and then in final he puts it back to 100%. I dont understand the reasoning behind it. If prop will do less rotations per minute by bringing “Blue” lever back what does throttle do then?  

 

 

Actually found a great article on this subject. So anyone with same issue of not knowing go here: https://www.boldmethod.com/learn-to-fly/aircraft-systems/how-a-constant-speed-prop-works/

It's basically like gears on a bike or car, where you use a low gear for rapid acceleration and manoeuvring, and a high gear for a more relaxed cruise at speed; prop fully fine/forwards for takeoff and landing, you can then coarsen the blade pitch (pull the blue lever back) for climb and further still for cruise and descent if you want.

If the engine is stopped in flight you go fully coarse (feather) which means the thin edge of the blade faces into the oncoming airstream, reducing drag.

Edited August 10, 20205 yr by ckyliu

3 hours ago, ckyliu said:

It's basically like gears on a bike or car, where you use a low gear for rapid acceleration and manoeuvring, and a high gear for a more relaxed cruise at speed; prop fully fine/forwards for takeoff and landing, you can then coarsen the blade pitch (pull the blue lever back) for climb and further still for cruise and descent if you want.

If the engine is stopped in flight you go fully coarse (feather) which means the thin edge of the blade faces into the oncoming airstream, reducing drag.

But in a technical way, if you push Blue lever and RPM rises that means prop is spinning faster right? And that happens because more fuel gets pumped into engine and rotor is able to spin faster. Then what does throttle do? I am little confused still

21 minutes ago, Lukamak said:

But in a technical way, if you push Blue lever and RPM rises that means prop is spinning faster right? And that happens because more fuel gets pumped into engine and rotor is able to spin faster. Then what does throttle do? I am little confused still

No, the RPM lever does not control the fuel flow, that is what the throttle does.

It is like a car... the throttle is the gas pedal, the RPM lever is the manual transmission.

26 minutes ago, Lukamak said:

But in a technical way, if you push Blue lever and RPM rises that means prop is spinning faster right? And that happens because more fuel gets pumped into engine and rotor is able to spin faster. Then what does throttle do? I am little confused still

The RPM is not directly related to throttle position. Just like in a car you can be at 50% throttle in 1st or 6th gear, the speeds will be very different. If you reduce the speed of the prop, the blade angle is adjusted so it takes a bigger "bite" of the air for the same throttle position.

Edited August 10, 20205 yr by ckyliu

To keep it simple, with an aircraft that needs to use the RPM lever,  full RPM for takeoff, then start lowering the RPMs according to the gauge to bring the needle into the green part of the indicator.  Probably around 2500 RPM.  I have watched the engines burst into flames on my C-47 if I did not lower the RPMs in time.