4 minutes ago, BigDee said:

Two questions here: I realized when using rudders in FSX, the plane changed its yaw orientation to approx.

I think you should stop thinking about FSX. The new sim might share a legacy mode and some code, but it's an entirely different story where it matters.

 

5 minutes ago, BigDee said:

Actually in my opinion they need to be good mathematicians and physicists.

I am sure they are very intelligent people that aren't quite that bad with mathematics and physics. The expertise can be gathered by consultants. That's the benefit of having one of the largest companies in the world backing you up. You don't need to do everything on your own.

1 hour ago, KenG said:

Blade Element Theory (BET) is not Computational Fluid Dynamics (CFD.) 

Something I've wondered for a long time, maybe you can answer it.

Is Blade Element Theory an appropriate use of technology in this case?

Hook

Ok, that should mean I did something wrong in FSX.

What makes FS 2004 better than FSX would be interesting to know.

And thaks for the BET info. It `s nice to read.

7 minutes ago, LHookins said:

Something I've wondered for a long time, maybe you can answer it.

Is Blade Element Theory an appropriate use of technology in this case?

I'm not Ken, but IMO it depends what you use it for.

For home flight sims and some other engineering tasks (for example: getting a general idea of your design) it sure is. For an aircraft manufacturer like Boeing or Airbus it sure isn't. Those companies tweak their aircraft to be as efficient as possible. BET is not accurate enough to draw conclusive information about that.

Edited June 25, 20205 yr by tweekz

I'm sure someone will give me flak or this but...

 

Though I'm not a real pilot, I felt Flight had dynamics that seemed more realistic.

1 minute ago, andyjohnston.net said:

Though I'm not a real pilot, I felt Flight had dynamics that seemed more realistic.

Microsoft Flight had a slightly slippery, "buoyant" feel in flight.  One thing that impressed me the most was in the Stearman, at least, you needed right rudder on climb and left rudder on descent, something I haven't noticed in P3D.  This implied that there was a sweet spot in the throttle setting where the plane flew perfectly straight with no left or right turning tendency.

Hook

7 hours ago, LHookins said:

Something I've wondered for a long time, maybe you can answer it.

Is Blade Element Theory an appropriate use of technology in this case?

Hook

When you don't know the aerodynamics, but you do know the shapes then BET will provide an approximation without having to instrument an airplane and collect test data. That is what Austin was after when he first built X-Plane, as outfitting an airplane with the speciality equipment and testing it is very expensive. Manufactures generally have this data and usually charge a huge amount for it. So for the economics of what is trying to be done, it works great.

The other great thing with XPlane was it wasn't constrained by conventional aircraft design, so an airplane like Rutan's Long EZ or the Beechcraft Starship are able to be designed and flown in XPlane and exhibit the unique aerodynamics of their nonconventional designs. 

However, for certified training devices the FAA (and EASA) want to track expected performance (flight test data) to simulator output. So while BET may be a great method of getting to the final aerodynamics solution, you are still stuck paying for the data. An interesting part of this is since the G650 was designed mostly via CFD when the first G650 FFS was built the flight data was heavily supplemented with CFD directly by Gulfstream. So while the G650 sim still had the Validated Training Envelope (VTE) the area outside the VTE was much more accurate than any previous sim and it was the first simulator approved for enhanced upset prevention and recovery training. 

Thanks, Ken.  Assuming it's "accurate enough," can it be fine tuned to get a more proper feel, as can be done with FSX/P3D?  This is one of the strengths of Microsoft's table driven approach.

Hook

3 minutes ago, LHookins said:

Thanks, Ken.  Assuming it's "accurate enough," can it be fine tuned to get a more proper feel, as can be done with FSX/P3D?  This is one of the strengths of Microsoft's table driven approach.

Hook

That is really getting into the weeds and something the Software Engineers would have to answer. However, I suspect with the computational capability of a modern FFS it is within the capability of the system, just how much more or less would it take to get to the same point as a table. I also wonder about the retraining of the team of engineers as they already know how to exactly tweak the tables. As a pilot flying the subjective QPS tests I may tell the engineer to transfer 20% of the 18 degrees flaps to the 35 degrees flaps and they do so in seconds. 

Ken:  I was speaking specifically of BET and XPlane. 🙂

@KenG i create aircraft with my CFD wind tunnel with moving shapes and then i take the aircraft into BET and love the real time, so i love Plane Maker and XP because i learn, is it possible to fill a data table without knowing much of an initial aircraft design before hand?

10 hours ago, LHookins said:

Ken:  I was speaking specifically of BET and XPlane. 🙂

Yes you can tweak things in Planemaker, but it is different. I would recommend searching for Planemaker as there are many resources.

9 hours ago, mp15 said:

@KenG i create aircraft with my CFD wind tunnel with moving shapes and then i take the aircraft into BET and love the real time, so i love Plane Maker and XP because i learn, is it possible to fill a data table without knowing much of an initial aircraft design before hand?

It is still only half of the solution. At some point you will need a certified pilot to test to make sure the final airplane flies and feels like the orginal. Unless you are going to make a new and unique design, in which case you know how you want your airplane to react. However, even in that case I recommend having someone with  flight test experience to put the airplane through its paces. There are some standards that a experienced test pilot can help you with as well as making sure the airplane complies with certification standards. 

5 minutes ago, KenG said:

Yes you can tweak things in Planemaker, but it is different. I would recommend searching for Planemaker as there are many resources.

So a table driven approach is potentially more accurate, given you have the correct data to feed into it?

I think a professional developer that is willing to put some effort into fine tuning can create great flight models like that due to its flexibility.

What will be interesting is how developers adapt to the new dynamics in MSFS. A lot of traditional FSX/P3D flight dynamics experts are going to have to learn a different way of doing things.

1 hour ago, KenG said:

A lot of traditional FSX/P3D flight dynamics experts are going to have to learn a different way of doing things.

Maybe not. 😄