Sign in to follow this  
rsrandazzo

[04JUN16] PMDG: Killing "Simmerisms" since 1997

Recommended Posts

Mr.RSrandazzo

      I do not really feel the need to mix my professional work life, and my hobby together. But since some users are unable to understand how thermodynamics works, I think it would be potentially valuable for the community if I offer my skills. I am a Mechanical Engineering who mostly looks at strengths of materials, but I have had to do a fair amount work on the life cycles of parts under thermodynamic loads. What I would like to do is a Computational Fluid Dynamic study of for the R-2800’s. In order to see what the equation the values should be based on the values that are used in the sim, vs the real numbers vs the CFD study. I know that we see very little if any difference between three. There is no one can argue with the numbers, so I think this will put a stop to the engine debate that people are having. I thought I once read claims of someone comparing your DC3 engines [i assume R-1830’s] to the engines in your simulated DC6. If this is the case, then I would like to try and get a CFD done on those to map the relative thermal similarity of the engine (at their hottest running conditions).

      I would not feel comfortable commenting on what I believe is happening or the misconception these people are “seeing” without being able to run the numbers through a couple different scenarios (prop-wash cowls closed, tail wind cowls closed with max/min prop wash).

      I only really fly x-plane so being part of Avsim community was not really a needed thing until I took a look at the forum to see what people were saying, and I could not believe it.

      I look forward to talking more in specific details, and working out a way to get this information to the masses.

 

Look Forward to Talking more,

Nick Paine

P.S. I cannot change the signature until 14 June. So that is why I signed here.

Share this post


Link to post
Share on other sites
Help AVSIM continue to serve you!
Please donate today!

I've seen at least one video, very detailed, going through a through review of flaws in the dc-6 ( which I must point out I do not own... ) but, excluding the part I can't comment on regarding engine modeling, and an initial introduction to the limitations of using the "AFE" on some flights without a "single" cruise level, it's  filled with inaccuracies and misconcpetions regarding overall principles of flight, and x-plane modeling of some aspects of lift & drag...

Share this post


Link to post
Share on other sites

 

 


filled with inaccuracies and misconcpetions regarding overall principles of flight, and x-plane modeling of some aspects of lift & drag

 

Could you be a little more specific though? Where was he wrong on "principles of flight"?

 

Katrín Eiriksdóttir

Share this post


Link to post
Share on other sites

For instance the simple references to dihedral effect, when he exits the sideslip situation and coordinates the turn - the circumstance under which dihedral effect is... nill ...

 

The interpretation of the "lift" vectors when the "Visual Flight Model " is enabled, and he comments on why a given vector is shorter than the other, not to mention that he wrongly assumes CCW rotating props when the dc-6 actually has CW rotating props, and so on.. and, even if this was a flaw, it would be an X-Plane core FDM flaw, and not a PMDG dc-6 model flaw....

 

There are other points though over which I agree with him, although again I believe they're due to the limitation imposed by the underlaying X-Plane core FDM - such as, for instance, rudder authority at cruise speeds and yaw-roll coupling...

  • Upvote 1

Share this post


Link to post
Share on other sites

 

 


There are other points though over which I agree with him, although again I believe they're due to the limitation imposed by the underlaying X-Plane core FDM - such as, for instance, rudder authority at cruise speeds and yaw-roll coupling...

 

Jose,

 

Are you type rated in the DC-6 or any other large radial airplane?

 

blaustern

Share this post


Link to post
Share on other sites

No.... far from that :-)   Not even a single, tiny little engine - Gliders only !

 

But if you're referring in particular to that sentence where I say I agree with him, what I mean is that X-Plane isn't great at modelling control forces with increasing "q"... It can be done using Plane-Maker, or scripting though....

 

I guess forcing the rudder of a dc-6, at that speed, would not only require a huge strenght from the pilot, but above all cause severe damage to the aircraft... IRL

  • Upvote 2

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this