Experiments to Learn

[Ivan]

Here is another old project that fits pretty well into the Diversion category.
This FW 190D-9 AFX was done by Alex Simon and seems to be the basis for numerous FW 190D and Ta 152 projects out in the CFS menagerie.

This is not the first time I have looked at making corrections to this project.
While the basic appearance of the finished aircraft especially those with textures by Hugh Shoults actually looks pretty good, there are plenty of hidden boogers that are very hard to correct.
From what I can tell, folks working with this project haven't generally tried to make any great corrections to it other than to move the Supercharger Intake from the Port to the Starboard side more typical of a JuMo engine.

As far as I am concerned, this project is pure experimentation and will never lead to a release of any kind.
If I want a FW 190 with an inline engine, it will be a conversion of my own FW 190A project.
At least there, I have a pretty good idea how big the can of worms is before I open the can.

This AFX was done before the rather casual SCASM edits we now throw in without much thought.
There are a few almost hidden parts near the CoG of the Model that are textured to almost provide a virtual cockpit.
I say "almost" because they don't really align with the other pieces of the model but at least they don't leave the model looking like a hollow shell in Quick Combat. Some of the other FW 190D based on this AFX actually use this feature.

Since I know that SCASM works better for the purpose, I decided to remove these pieces.
This brings up another bit of strangeness with this AFX and the zip file containing it.
Although the Assembly had the Parts and they were textured, they did not show as textured in AF99.
Also, the textures that were used by these pieces were not included in the zip file.
I could easily pull them from any number of other FW 190D downloads, but thought it was such a goofy way of doing things, that it was not worth the effort.

I decided to simply remove those pieces from the Assembly.
One might notice in the screenshot that nothing is animated.
This is because in removing those virtual cockpit pieces, the model was changed enough that Aircraft Animator no longer recognizes the pieces it is supposed to animate.

This brings up another point. Has anyone else wondered how Aircraft Animator recognizes pieces that it needs to animate?
I found out a year or two ago that it is actually by the SCASM label for the pieces. (!)
As long as the AF99 edits don't change those labels, prior animated pieces will be recognized (mostly).

So why am I still wasting time on a project that I know will go nowhere?
There are a few things that are done in this project that I never do on my own projects.
I can experiment with those features to see if I can improve them to the point where they become a reasonable thing to add to my own projects. If I fail and damage something, it was a throwaway project anyway and these assemblies tend to be much less complicated than ones in my projects.

It is also very satisfying to make a few simple changes and see some noticeable improvements.

- Ivan.

[Ivan]

A few additional pieces were added to this model:
Flap Wells, Landing Gear Wells, the Pilot was added a while back.
The Supercharger Intake was also moved to the correct side for a Jumo 213 engine.
The Flaps themselves are a bit more complicated now.
Earlier they were textured the same as the trailing edge of the Wing.
That meant that the inside of each Split Flap was the same as the Wing Upper Surface.
Those surfaces normally don't carry camouflage paint so this was certainly incorrect.

In playing with the propeller animation, I found that this flight model was basically that of a FW 190 with a radial engine.
The Jumo 213A that was developed for the Engine Tuning Tutorial was installed in its place and now I am finding that the Propeller is quite inadequate to handle the level of torque and power that the new engine is giving.

This seems like a good enough model to use to develop a flight model for the FW 190D.

- Ivan.

[Ivan]

Yesterday, I went into the "Library" and found a couple really good references for the FW 190D-9.
One of the references is in German and my reading is extremely slow.
The other is in Japanese and I can't read that at all.

One had some good dimensional drawings which are almost certainly good enough to convert my FW 190A into a "Dora".
In the drawings, I found that the propeller diameter that I had been using was almost certainly incorrect.
Correcting the diameter actually puts the Propeller Power Coefficient much lower which altered the Idle Speed but didn't change the engine output.
There was other information that needs to be reconciled for the flight model and THAT may mean that the current JuMo 213A-1 needs a slight rework for power levels. It won't change that much, so it makes better sense to do this after a proper propeller with Wide Virtual Blades (Higher Power Coefficient) has been built for this engine.

After finding the "correct" Propeller Diameter in the drawings, I noticed that the Propeller Diameter in the visual model was off by slightly over 6 inches. This took about 30 minutes to correct. Perhaps I should check other critical dimensions as well.
The drawings also showed that the piece of armour to protect the pilot's head and back is missing from the model although the headrest and support are present.

Attached are screenshots of the corrected propeller.

There seems to be a lot of variation in the equipment installed in the Dora-9. Some had outboard wing cannon. Some did not. Some had the ETC 504 weapons rack and some did not. Some were conversions from the A-8 series "Wrack"s and had the earlier non-blown canopy with the older canopy supports and some had the newer solid support more typical of a A-9/F-9 or ground attack birds.

My flight model thus far is somewhat contradictory. It has MW 50 for a power adder but also has the 115 Liter Aft Fuselage Fuel Tank. Either the Water Methanol OR the 115 Liter Fuel Tank could be installed but not both. Since I still plan on using the standard FW 190A Fuel Selector, I may just convert the Aft Tank into the small Priming Fuel tank that was also present. The details still need to be worked out.

That is the reason for working with a throwaway model. All the mistakes get to be made here.

- Ivan.

- Ivan.

[Ivan]

The 6+ inch Propeller diameter discrepancy should have been a pretty good indicator that there might be other issues.
I was about to make some corrections to partitioning of Components in the Fuselage and also add the missing Armour behind the Pilot and decided to do a quick check of overall dimensions. The results were surprising.
The overall length is 3-4 inches too long, and the wing span is nearly TWO FEET (actually 1.78 feet) too long. This is some of the easiest information to get before starting a project but it doesn't seem like it was ever done here.
Very disappointing.

- Ivan.

[Ivan]

It turns out that the Wing Span was actually 1.80 Feet too long.
I decided to try a fairly low effort fix.
The screenshots show an intermediate stage. (I haven't finished the fixes yet.)

The Wing Tip and Ailerons were combined into a AF99 Component which I called X1.
I then used the CMoveIt (Component Move It) Utility I wrote a few years back to shift the entire Component Inboard by 0.90 feet and Down by 0.07 feet so that the Parts would telescope into the Inboard Wing Section.

The Wing Tip Chord is also a bit too short, so the Wing Tip X1 Component will be slightly magnified (by around 3.5%) to better match the lines of the inboard section.
This won't actually correct all of the size issue of the Wing Tip Chord but it will be closer than it was before.
A proper correction would require a full rebuild of the Wing and I have no intention of putting that much work into this project.

There are also some discussions which suggest that the Overall Length of the FW 190D-9 is actually longer than typically reported.
The length of this model would still be a bit long but is probably not worth fixing.

- Ivan.

[Ivan]

The Wing Tip and Aileron (combined into Component X1) was stretched Longitudinally by a factor of 1.032.
There were no changes in Vertical or Lateral dimensions. After that, the adjusted X1 Component was moved to match the inboard Wing section.
This was a very simple process using command line utilities once the degree of adjustment was determined for each stretch or shift.
After that, a reference Part was created from the end of the Wing inboard section and Wing Tip and then a Station Template was created which was the average of those two Parts.
Once the Parts of each Wing Component were adjusted to match the new Station Template, the task was basically done except for moving the Pitot Tube to match the new Wing Tip. A bit more measuring, three calls to utilities and that task was also done.

Texturing for this model is extremely basic and was not hard to correct. It still is not optimal, but is no worse now than it was before except that the crosses on the Wings are very slightly more distorted.

- Ivan.