Limitations of PrPNK and ABRIS integration: why?

[sinelnic]

Hello there!

 

I started studying the nav systems of my chopper with the assumption that the inertial and satellite systems were totally unconnected. It took me a while to make a rudimentary map of the navigational/targeting systems of the Ka-50, finding out that in fact the PVI-800 is a mere interface to a couple more systems that make the PrPNK which also feed the AP, targeting system, etc, with the INU/PNK-800 at its core.

 

Now it took me little more to find out that there ARE some integrations built between ABRIS and the PrPNK, for instance the designation of target points for DL, and the display of the Shkval aiming point in the ABRIS. So basically input from the PNK-800 to the ABRIS is already in place, I assume with all the circuitry for data format transformation and communications protocol (input only).

 

So my question is why is there not a similar integration for automatic or even manual INU calibration from the ABRIS (when satellites are up) or, more importantly, waypoint and targeting input from the ABRIS to the PNK-800? With little planning this could be done in a way that would still allow the pilot to seamlessly operate with the PVI-800 in case of satellite system malfunction.

 

I'm currently theorizing that maybe the integrations were made directly from the I-251V (Shkval) to the ABRIS, so 3D positioning calculation is done in ABRIS from the directional info that the Shkval provides, and not coming in coordinate form from the PNK-800, hence no actual integration was built between the two nav systems because of a very good reason. But I'd like to know, if possible, the concrete technical answer to this, as it seems to me this lack of integration is a shortcoming on the design goal of lowering the pilot's workload (whereas in other cases Kamov went in great effort to provide good solutions for this problem), and the kind of problem that a young, smart and ambitious russian enginneer would have volunteered to solve!

 

Well thanks in advance for any responses!

[Panzertard]

From what I've learned, thats how the Ka-50 is due to the fact that the PVI was in place during design, while the ABRIS was inserted much later.

 

Here: http://forums.eagle.ru/showpost.php?p=651915&postcount=10

Edited August 1, 2009 by Panzertard

[sinelnic]

From what I've learned, thats how the Ka-50 is due to the fact that the PVI was in place during design, while the ABRIS was inserted much later.

 

Here: http://forums.eagle.ru/showpost.php?p=651915&postcount=10

 

Thanks Panzertard!

 

That would be the economic part of the answer, appreciate it. But since some integrations where made, I'm interested in the technical aspect of the difficulty, just to improve my knowledge of the systems. I have lots of curiosity and a little time to spare...

[EvilBivol-1]

I don't think there is a definitive answer, however as far as I know the tactical information displayed on the ABRIS is equivalent to what was originally displayed on the TVM before the ABRIS was installed.