La 5 inlet cowl shutters affect speed

[Pruciak]

Do the La 5 inlet cowl shutters affect speed in any way or should I keep them open all the time? Any tips regarding a fight against 109 would also be much appreciated. Tried a turn fight but i always loose. I only win when I get one by suprise. Thx in advance :-)

[Matt]

They affect speed a bit, but you basically have to leave them fully open anyway to prevent overheating the engine. Only advantage you have against the 109 is better roll rate and slightly higher speed at ground level when using boost (which you can't use for long without overheating). If you are at the same altitude as your opponent, there's not much you can do. So try to be above him for get a wingman.

[6./ZG26_Klaus_Mann]

Do the La 5 inlet cowl shutters affect speed in any way or should I keep them open all the time? Any tips regarding a fight against 109 would also be much appreciated. Tried a turn fight but i always loose. I only win when I get one by suprise. Thx in advance :-)

Yes, but so little it doesn't really matter. They ecist so you don't freeze the engine on landing approach. 

[Crump]

They should affect speed by about ~50kph according to the Operating Instructions....

 

[RFG_Hisl]

This picture shows outlet shutter (which affekt speed) and oil radiator, not inlet shutter.

Edited July 13, 2017 by RFG_Hisl

[Crump]

 

 

This picture shows outlet shutter (which affekt speed) and oil radiator, not inlet shutter.

 

 

Except for the fact the oil radiator inlet shutter are part of the management of the oil radiator system and will affect speed as depicted.

 

From what I gather in reading the Operating Instructions, the radiator inlet is either opened or closed.  You want it closed for example in the winter time for starting/warm up and when the oil reaches the correct temperature, it comes open and stays open.   It looks like it a built in oil cooler cover so you do not have to install one every time winter comes around or you are doing cold weather flying.

 

It is not meant to be adjusted outside of either being open or being closed.

 

The outlet shutter is the primary control for adjusting oil temperature when the inlet is open.

 

 

 

 

Some manufacturers provide baffles, winter front covers, and oil cooler covers, as optional equipment items for winter operations.

 

http://www.mountainflying.com/pages/articles/winter_woes.html

[Pruciak]

Thank you for quick replies. So in order to fight with the 109 which plane should I choose (except Yak)?

[Voidhunger]

In my experience when i adjust inlet shutters the engine overheat very quickly even on cruise settings. And when i return them in open position the engine keeps everheating.

[Crump]

 

 

In my experience when i adjust inlet shutters the engine overheat very quickly even on cruise settings. And when i return them in open position the engine keeps everheating.

 

I just leave them open.  If I baby the engine and set cruise power then the engine is pretty robust in combat.

 

In fact I have never had one fail.  I have only used emergency power a handful of times too.  

The La5 is one of my favorites rides in the game. 

[Guest deleted@50488]

Yes, the La5 is a charm to fly, but I somehow still prefer my first IL-2 Battle of Stalingrad love - the LagG3 :-)

 

I always leave the shutters ( inlet ) fully opened, and only manage the outlet - those do affect speed very noticeably.

 

For descents at low power settings and in Winter time, I set the inlet shutters to 20%

[MiloMorai]

 

 

Except for the fact the oil radiator inlet shutter are part of the management of the oil radiator system and will affect speed as depicted. From what I gather in reading the Operating Instructions, the radiator inlet is either opened or closed.

 

Where is this inlet shutter located?

[Matt]

Thank you for quick replies. So in order to fight with the 109 which plane should I choose (except Yak)?

The 109 (G-2 and F-4 at least) outperform all Russian planes. I personally prefer the LaGG-3 to the La-5, but i wouldn't say that it is better. Overall, the Yak-1 is the best all around fighter on the Russian side. The Mig-3 has a pretty bad climb rate, the I-16 is too slow and the P-40 too sluggish and if you want to get the best performance out of it (which is still not that great, especially in the vertical), you'll spend a lot of time adjusting RPM and throttle.

[-=PHX=-SuperEtendard]

It is built into the opening in the front of the cowling. Looks like teeth as it closes!

 

Yep

 

 

Wouldn't closing them make more drag than having them open? As the air would have to skip the nose instead of flowing through it... If i'm wrong feel free to correct

[[CPT]Pike*HarryM]

If open then the air would just be hitting the cylinders in the engine, so it wouldn't exactly be a free-flow right through. 

[6./ZG26_Klaus_Mann]

Yep

 

 

 

Wouldn't closing them make more drag than having them open? As the air would have to skip the nose instead of flowing through it... If i'm wrong feel free to correct

Minimal Difference. The main reason they exist is to maintain engine temperatures when low Power is applied and while landing. Freezing an engine is just as dangerous as overheating it. 

[MiloMorai]

It is built into the opening in the front of the cowling. Looks like teeth as it closes!

 

Yes for the engine (the I-16 has also) but where for the oil cooler?

[[CPT]Pike*HarryM]

Oil cooler is on the bottom of the engine, the control opens and closes the flap on the back of it. So three controls. inlet on front of engine ("teeth") the outlet shutters ("ears") and the oil cooler flap (<insert appropriate body part here>).

[Crump]

 

 

Wouldn't closing them make more drag than having them open? As the air would have to skip the nose instead of flowing through it... If i'm wrong feel free to correct

 

Yes, it needs to be open and it is designed to have a little cooling pressure. 

[A_radek]

 

Wouldn't closing them make more drag than having them open? As the air would have to skip the nose instead of flowing through it... If i'm wrong feel free to correct

Won't pretend to understand this any better than you, but no.

The turbulence created inside the cowling creates so much drag that the lesser evil, having them closed, is better. If this was not so the I-16 would also benefit from having them open at all times, instead of having that huge circular barndoor up front

[Crump]

 

 

The turbulence created inside the cowling creates so much drag that the lesser evil, having them closed, is better. If this was not so the I-16 would also benefit from having them open at all times, instead of having that huge circular barndoor up front

 

That is not how it works.  Read the Operating Instructions.  The inlets are left open except for cold weather starts.

You leave them closed and when the Cylinder head temperatures reach a certain level they come open and stay open.  In fact, it specifically warns against leaving them closed because the CHT's will increase beyond redline before the oil temperature warms.

That is exactly what would happen in flight.  Without cooling pressure of ram air, the cylinders would cook in a short period of time.

[Y29.Layin_Scunion]

Take into account as well that the oil radiator being fully open does not have a serious effect on air speed. It was built to be aerodynamic so having it open is not detrimental.

 

One thing less to worry about in a fight which is nice. For a while I did not know this and would adjust it in combat.

[A_radek]

That is not how it works.  Read the Operating Instructions.  The inlets are left open except for cold weather starts.

You leave them closed and when the Cylinder head temperatures reach a certain level they come open and stay open.  In fact, it specifically warns against leaving them closed because the CHT's will increase beyond redline before the oil temperature warms.

That is exactly what would happen in flight.  Without cooling pressure of ram air, the cylinders would cook in a short period of time.

 

Crump, I think you missunderstood me.

 

Superentendard simply asked which alternative would cause less drag, Closed or open, And I presented my theory on it.

 

I'm still not sure If you agree with me or not

[Crump]

Crump, I think you missunderstood me.

 

Superentendard simply asked which alternative would cause less drag, Closed or open, And I presented my theory on it.

 

I'm still not sure If you agree with me or not

 

While it might seem intuitive that closing them would be less drag, like many things in aerodynamics...the reality is counter-intuitive. 

 

There is generally with all cooling installations a point where cooling pressure is optimized and the outlet pressure presents the effect of a reduction in drag.

 

I am sure Lavochkin know this and used it in the design.  You can see the attention given to drag reduction by the large effect on speed.  That speed comes with the inlet open and outlet set to an optimum exhaust point.

I roasted my La-5's engine in a short period of time by forgetting to open mine after start on a winter map!

 

Very sadness. Much disappointful.

 

Yeah I roasted mine closing the inlet too.

It's something I love about the user manual literature of the era, it so often has a 'cute' cartoon or 'saucy' appearance. The sort of thing I expect from old British seaside postcards. When I see this style being used for RAF flight guides or Tiger I literature and other weapons of war it strikes me as both beautiful and darkly sinister.

 

I love the cartoon manuals.  Yeah, it was just a way to take a young man's mind off the grim reality of war but still emphasize information he would need to save his life.

[A_radek]

Crump, I see. Then I stand corrected.

 

Though with my very limited knowledge of aerodynamics, I fail to understand how an outlet/inlet can reduce drag. Even when in perfect harmony. Is it the air inside the cowling expanding due to heat that somehow produces forward thrust and compensates for the drag created by the inlet/outlet arrangement?

 

Only thinking out loud. Perhaps I misunderstood you altogether.

[56RAF_Roblex]

Crump, I see. Then I stand corrected.

 

Though with my very limited knowledge of aerodynamics, I fail to understand how an outlet/inlet can reduce drag. Even when in perfect harmony. Is it the air inside the cowling expanding due to heat that somehow produces forward thrust and compensates for the drag created by the inlet/outlet arrangement?

 

Only thinking out loud. Perhaps I misunderstood you altogether.

 

Think of a motorbike exhaust, or a cars to a lesser extent.   They could just exhaust the gases straight out from the cylinder into the air, nothing to impede the flow so surely better at venting the gases? but not true. The length and shape of the exhaust pipe actually makes the gas flow more efficient.   Those kids who swap the exhausts on their cars for a 'fatboy' that sounds meatier end up with less powerful cars.  Think also of F1 car designers who add extra items or divert the airflow throug channels, more drag right?,  that actually reduces the overall drag  The aircraft designers have optimised the airflow within the cowlings to flow through with less drag than air hitting a closed cowl inlet flap.   

[ACG_KaiLae]