FS9.1 Prop Spinning Up Speed

[G-SWSM 1]

Hi All.I was wondering if there is a way of Slowing down the speed at which the prop blades start to spin up on engine start.I like flying the prop planes, but have always felt that they spin up way too fast.Is there a way of slowing this down do you know.Thanks in advance for any help.

[ronzie 21]

in aircraft.cfg:[propeller]propeller_moi=22.000Here's an entry from a payware ATR 72-500 I have:propeller_blades=6 propeller_moi=90and from the default King Air:propeller_blades = 4 //Number of propeller bladespropeller_moi = 24 //Propeller moment of inertiaand from the default C172:propeller_blades= 2 //Number of propeller bladespropeller_moi= 5.0 //Propeller moment of inertia Moi is the moment of inertia. If you increase it you may load the engine more so it may change its acceleration lag performance. I don't think the prop will shatter at high shaft speeds.Now turbine powered prop aircraft (turbo-props) really do spin up slowly due to what is called turbo lag and is referred to as turbine engine spool up. That is why they have have a flight idle mode to reduce the lag on power change commands to reduce that lag time.As always, backup up aircraft.cfg before editing with Notepad.

Hi All.I was wondering if there is a way of Slowing down the speed at which the prop blades start to spin up on engine start.I like flying the prop planes, but have always felt that they spin up way too fast.Is there a way of slowing this down do you know.Thanks in advance for any help.

[G-SWSM 1]

Hi.Thanks for the reply.So, in my Team FS KBT P3C I have the following for the Prop MOIpropeller_moi=120.000If I wanted to slow it down what would I put in there, a higher or lower figure to slow it down?Thanks.and yes, I will back up the cfg first.Thanks again.

[ronzie 21]

The FS9 Container SDK documentation does not give an acceptable range. To me that sounds high. What kind of aircraft is it? Perhaps if you give too high a value FS overloads and in effect it is a really small value. Is this a chopper?

[WhiteKnight77 0]

If it is what I think it is, it's a turbo prop as in P3 Orion, sub chaser.

[G-SWSM 1]

Hi.yes it's the sub chaser by team fs kbt.a great freeware plane, bt like all the turboprops te spin up speed looks silly, so I wondered if it could be slowed down.Thanks.

[ronzie 21]

The prop condition lever is normally at full rpm. When a turbine ignites the N1 speed is higher than the selected ground idle and then slows down. With a tight coupled prop it night spin up fast and then slow down.The King Airs I believe all have a loose coupled prop shaft on the turbine in the r/w. They will windmill in a breeze with engine off. I don't recall aircraft specifics but some loose coupled props have their governors set up so that on loss of air pressure the governor hydraulic pressure on relaxing flat blades (feathers) the prop to prevent windmilling under engine off since lack of prop lube oil could damage stuff under those conditions. It is not unusual to see some turbo props red flagged with a prop rope tie to prevent movement.When I get time I'll crank up this model and see if it follows as typical turbine start.Except for the start-up comment these are recollections.In the meantime on a startup observe the action of your N1 and N2/prop rpm gauges. Try a few different turbo-props.

[G-SWSM 1]

Hi.so the general consensus seems to be that if I alter the moi thingy then this would also affect the performance of the aeroplane too!Oh well. Thanks for looking and trying anyway guy's.