Finally found how the Lavochkin La-5 and La-7 engine cooling shutters worked

[Captain Kurt]

I never found anything in the La-5 references I used but when I started researching the La-7 instead I found this in a Polish MBI publication:



From the illustration and photos I have, I can tell the individual shutters pivoted on the pin in the right hand corner and rotated to the left. (facing the nose) It also tells me what position the shutters were in when fully open.

So now I can update the La-5FN with working engine shutters. Won't be real quick, as there are 24 individual shutters and each has to be animated separately. But you can look for a new version of the La-5FN in a couple of days.

 

[hertzie]

Looks like the "system" they used on the I-16 Moskva.

hertzie.

 

[normb]

Thanks for the info. Pretty neat.

 

[Captain Kurt]

Looks like the "system" they used on the I-16 Moskva.

hertzie.

Same principle controlling air flow, but it's a lot more complex than that. The I-15 / I-16 just used a flat plate with holes cut in it which was rotated to either align or close the openings of another plate to let air in or keep it out. The Lovachkins use 24 separate louvers each of which pivots on its own, coordinated through gearing with all of the others.

The Shvetsov M-82FN engine had cooling problems and required more air flow and sophisticated handling to keep it from over-heating. The Polkarpov M-25 engines (which were license built Cyclone copies) didn't have bad cooling problems. The adjustable plates on the Polikarpovs couldn't allow the cowling to be opened completely but M-25 didn't need that much air flow, whereas the M-82 definately did.

Anyway, you'll see when I get it finished and posted.

 

[hertzie]

Thanks for the explanation, captain. You're never too old to learn