Adjusting prop animation RPM?

[gecko]

I'm having a bear of a time messing around with a new propeller FM for my early Mk I Spitfires. The main problem is that the animation of the prop doesn't switch from using the spinning model of the propeller blades to the blurred prop texture until 750 RPM. This is way too high, and so far I haven't been able to make the changes I hoped and keep my idle RPM above this number. I'm guessing the speed for this transition is coded into the model somehow and can't be changed, but I had to ask. Does anybody know if it can be adjusted?

[gecko]

Well, I've answered half of the question. It seems it can be adjusted. I swapped m3d files with an aircraft that shows the prop disc at a lower RPM. When using the aircraft.cfg, .xdp and .air files of my problem aircraft it made the switch at 750 RPM just like the original model. Now I've got to figure out why....

[gecko]

Found it. I adjusted the max rated RPM up too high as part of getting rid of some of the effects of the prop governor. Set it back to a more reasonable level and all is as it should be. Always nice to have a conversation with yourself in public.

[NachtPiloten]

Yeah I lie it when the engines idle around 650-700 and you can see the slow prop. Exactly what did you do?

Oh, you need to make a sticky with these adjustments you are making for the prop profile so I can redo my new planes (oh, did I say new......)

[NachtPiloten]

should be "like"

[gecko]

I will eventually report on my findings, right now things are very experimental. I prefer the fully blurred disc myself. I'm around spinning propellers almost every day and I've found you can't really make out individual blades until under 300 RPM, where the engine is just barely firing if it can even maintain RPMs that low. As you get up into normal operating range, it gets pretty hard to even see the prop at all, much less the individual blades. In this case though, I was still seeing the actual 3d blades at 750 RPM, not even blurred blades. The max rated RPM value from the engine section of the aircraft.cfg was the culprit here. I had it set really high for other reasons and found it affected the prop animation.

I wonder what surprises you have in store!

[Milton Shupe]

FS2004 and earlier transitioned to the the blurred prop at around 468 rpms of the prop. (not sure about CFS3)

I am curious if you are using or have a "geared prop" and as a result, the prop is turning less than the required rpms to change over.

Cfg statement example: gear_reduction_ratio = 1.5

If the ratio is 1.5:1 engine/prop then engine must be over 702 rpms for the prop to change.

[gecko]

It is geared, 2.096 for a Merlin III. CFS3 seems to handle it a bit differently as I have been able to change the speed that the transition occurs.

I now have a properly working manually adjustable two-pitch propeller. However, the propeller tables in the .air file are way off. You can get away with it with a constant speed prop because the prop governor hides problems by constantly adjusting the blade pitch. I've effectively removed the governor (CFS3 still thinks it's there) so now I've got to dive into those tables to make the performance numbers work out. This won't be fun...

[gecko]

Success! I've finally beat my head against those propeller tables long enough to get some decent results. My Spitfire has a working two-pitch propeller which operates at the appropriate RPM at airspeeds and altitudes which correspond to test data to within a couple RPM, MPH and feet. These produce the correct airspeeds and climb rates. I've also added a new way to kill your engine. Overreving your engine beyond the limits specified in the pilot's notes (easy to do with this manual propeller) will make your engine quit. You can fly this airplane by the book, using the officially recommended power settings, and the numbers work out pretty well. I am just tuning up a few things and then I will work on releasing it with notes so others working on FMs can benefit from my experiments.

[HouseHobbit]

This is very interesting for me, looking forward to using this on some of the underpowered bombers that have such a hard time getting rolling for take offs when loaded..
Many Thanks..

[sdsbolt]

sounds impressive

[gecko]

Thanks guys. Steve, if your Mk VIII should ever morph into a Mk I you're welcome to use it.

[Pat Pattle]

Have been reading this with interest, can you send me the files to play with please Daniel?

Its always bothered me why the engines don't stop if you thrash around at full throttle, very glad you've cured that one.

On a similar vein, when shooting up a bomber I've never seen one of their engines stop through damage/coolant loss etc. I've seen a lot of real footage where this happens. Could what you're investigating help with this too?

[gecko]

Well, it isn't totally cured, but it is a little better. Exceeding WEP allowance has always caused damage (but not stoppage) and now we have a very primitive means of punishing you if you exceed RPM limits, though in reality managing a real engine well is way more complicated than we can currently simulate in CFS3. This plane ought to be a step up though, as it is intended to be flown by the original pilots notes from startup to shutdown.

Not sure why I got stuck on this, need to get back to testing Ankor's creation in CFS3, I'm apparently getting behind!