My experience is that it makes no difference if and when I close or open the cowl flaps.What effect should I see if I set them wrong both in FS9 and realworld.The planes I have flewn and have in mind is Baron 58 (both default and DF) FSD Seneca.

Yes, no, maybe.They DO make a difference in many aircraft. They lower CHT and Oil temp when open, but no they dont seem to add any drag or change the flying characteristics. And failing to use them properly CAN lead to some addon aircraft engines going `phut`. FSD have damage modelling built into some of their airplanes for that reason. DF don't.So yes, no and maybe is the answer.:)Allcott

I've never noticed one impact from leaving them open vs closing them. I forget about them all the time (either never closing them or leaving them closed for landing). I've never had it bite me, even with FSD planes.

It makes a difference in real planes. It cools the engine by opening it...and when you descend you close it to keep it warm in case of go arounds.In engine out practice (twins), you close the cowl (of the engine that you have shut down or throttle down) to make sure you keep it reasonbly warm.In cruise, it gives slightly better performance when it is closed.But in terms of importance... Its not that important as say flaps etc.. Its just another parameter to maintain engine temperature.http://stoenworks.com/Tutorials/Cowl%20Fla...Engine%20C.htmlhttp://www.avweb.com/news/columns/188945-1.html

That's because most FS models don't take them into account.In those that do you notice a difference.Slightly more drag when open, engine temperature drops, etc.

Only the impact on temps is modelled by FS. Some add-on companies have decided that the induced drag is more important. In this case they are somehow linked to the airbrakes. If I remember right, the FSD Commander 115 had this feature (or maybe other planes from FSD). But than you lost the impact on temps.In real life you would not forget them as you would notice the low airspeed.BTW with FSUIPC registered you can add cowl flaps to an axis if you have one left.Alex

>In engine out practice (twins), you close the cowl (of the>engine that you have shut down or throttle down) to make sure>you keep it reasonbly warm.They generally call to do it in a real situation too as it helps yaw the plane a little towards the live side, theoreticly reducing the amount of rudder force. By how much I have no clue though.----------------------------------------------------------------John MorganReal World: KGEG, UND Aerospace Spokane Satillite, Private ASEL 141.2 hrs, 314 landings, 46 inst. apprs.Virtual: MSFS 2004"There is a feeling about an airport that no other piece of ground can have. No matter what the name of the country on whose land it lies, an airport is a place you can see and touch that leads to a reality that can only be thought and felt." - The Bridge Across Forever: A Love Story by Richard Bach

realism down = no effect with cowl flaps.realism up = major difference. At least on my sim.

I meant that I don't know in real life how much of a difference in needed rudder force is when you drop the flap on the live engin and raise it on the dead. I'm not quite yet to the Mutli flying, but I've already been through the ground school.----------------------------------------------------------------John MorganReal World: KGEG, UND Aerospace Spokane Satillite, Private ASEL 141.2 hrs, 314 landings, 46 inst. apprs.Virtual: MSFS 2004"There is a feeling about an airport that no other piece of ground can have. No matter what the name of the country on whose land it lies, an airport is a place you can see and touch that leads to a reality that can only be thought and felt." - The Bridge Across Forever: A Love Story by Richard Bach