I-16 Negative G's Starving

[Ace_In_Exile]

Hi pilots,

As the title suggest i'm here to discuss about the absence of a modeled negative G's cutout of the Rata since it is equipped with a carburetor. If i'm not wrong the i-16 was really sensitive to neg G's cutouts.

[JtD]

There's about two hundred different kinds of carburettor. Only float type carburettors are really sensitive to negative (or near zero) g's. The vast majority of Soviet aircraft were powered by carburettor fed engines (exception would for instance be the Ash-82FN), but hardly any of them used float type carburettors. Most of them had some sort of injection/pressure (i.e. floatless) carburettor, which is no more sensitive to negative g's than a direct injection. The M-63 engine used in the late I-16 versions came with a floatless* carburettor, and therefore is not in immediate trouble every time you push the stick. Like in other aircraft, negative g will cause the fuel pump to suck air in the main tank, and after a while the engine will starve. Additionally, the oil pump will suck air, which may lead to engine damage in prolonged negative g situations.

 

*Edit: Correction: It came with two types of float carburettors. They were quite complex, and avoided flooding/starvation of the carburettor by various means. The most simple was an orifice, similar to that used on early Rolls Royce Merlin engines, in the high throttle regime. Bottom line is that they weren't easily flooded/starved in negative g condition. I've read the statement that it didn't happen period, but don't understand the working details of the carburettors used well enough to verify this statement.

Edited July 29, 2016 by JtD

[Ace_In_Exile]

Thanks for the explanation, that makes sense why the rata doesnt suffer this kind of cutouts.

Thanks again for replying.