Ask for some advice on La-5，thank you.

[Fuyi_Adawa]

Hello everyone!
Recently, I was flying La-5 and La-5FN, and some problems bothered me.
1, The plane has engine inlet cowl shutters control and engine outlet cowl shutters control. Can I set two operations to the same axis or a pair of keys?
2, During the states of takeoff, climb, cruise, and combat, how many radiator percentage (including oil radiator and air shutters) are set properly in flight? 
Thank you very much for your advice.

[56RAF_Roblex]

1. Yes you can but it would not be a good idea (see 2)

 

2. The outlet cowl rarely needs more than 0 (10% at most) and has a big impact on drag.  The inlet cowl can be left at 100% as it has no effect on drag. Oil is usually 100%

 

 

Edited March 29, 2022 by 56RAF_Roblex

[Fuyi_Adawa]

2 hours ago, 56RAF_Roblex said:

1. Yes you can but it would not be a good idea (see 2)

 

2. The outlet cowl rarely needs more than 0 (10% at most) and has a big impact on drag.  The inlet cowl can be left at 100% as it has no effect on drag. Oil is usually 100%

 

 

Okay. Got it. Thank you.

[cardboard_killer]

Always check out requim's videos as they are very informative for new planes.

 

 

[56RAF_Roblex]

24 minutes ago, cardboard_killer said:

Always check out requim's videos as they are very informative for new planes.

 

 

 

 

I love his videos and watch them all but he has a tendency to give you engine settings that are only suitable for someone taking off then landing immediately.   For that reason I would caution against his advice to open the Outlet Flaps fully unless you are going to be sitting parked for a long time with the engine running on a very hot day.  Those outlet flaps are huge airbrakes and opening them fully reduces your speed by 35-40km/h
Similarly,  I advised inlet & oil flaps to be left at 100% but if flying on a very cold day, eg under -20C,  you might reduce the oil a little if you see the oil temp running too cold and sometimes a long fast dive can overcool the engine.

TLDR.   While flying you will rarely need to open the outlet flaps and if you do then you are unlikely to need more than 10% or open them wider to solve an overheat then close them again quickly.    Inlet & Oil flaps do not affect your speed at all (OK I think one of them makes 1-2 km/h difference) so 100% is an easy 'save & forget' setting unless it is really really cold.  Use those settings to start then make small adjustments if needed.

Edited March 29, 2022 by 56RAF_Roblex

[cardboard_killer]

16 minutes ago, 56RAF_Roblex said:

For that reason I would caution against his advice to open the Outlet Flaps fully unless you are going to be sitting parked for a long time with the engine running on a very hot day. 

 

Where does he state this?

[56RAF_Roblex]

5 minutes ago, cardboard_killer said:

 

Where does he state this?

 

Before he starts the engine he says you should either close the outlet flaps or open them fully then just before starting his take off run (about 4 minutes) he says to open the flaps and you can see the Outlet flaps fully open.   He does not close them again until he lowers his undercarriage.

[cardboard_killer]

4 hours ago, 56RAF_Roblex said:

his advice to open the Outlet Flaps fully unless you are going to be sitting parked for a long time with the engine running on a very hot day.

 

This is not this:

 

3 hours ago, 56RAF_Roblex said:

Before he starts the engine he says you should either close the outlet flaps or open them fully then just before starting his take off run (about 4 minutes) he says to open the flaps and you can see the Outlet flaps fully open.   He does not close them again until he lowers his undercarriage.

 

[56RAF_Roblex]

Ah I see your confusion.... 

 

What I was saying was I would caution against his advice to "open the Outlet Flaps fully" unless you are going to be sitting parked for a long time with the engine running on a very hot day.  Only the part in quotes was what he said. 

 

Edited March 29, 2022 by 56RAF_Roblex

[Dragon1-1]

Once nice thing you can do is use the outlet flaps as actual speedbrakes.  On occasion, you find yourself too fast, and simply chopping throttle doesn't do it. Besides that, they're only used on very hot days or when idling the engine on the ground for a long time.

 

Inlet flaps stay fully open unless you're worrying about overcooling the engine. Oil, you just try to keep at operating temperature. It doesn't do much to your speed, although it does do more than the inlet flaps, so if you really have to go fast, you can close it fully (just remember to open it before the oil gets too hot).

[Fuyi_Adawa]

2 hours ago, Dragon1-1 said:

Once nice thing you can do is use the outlet flaps as actual speedbrakes.  

Good idea?. When deceleration is required, such as approach.