Prop animation?

**skyhawka4m** · January 2nd, 2013, 21:32

Can someone tell me how I can change the length of time the prop spins down to a stop? What I would like to do is have a prop spin down to a complete stop but take a bit longer than a shut down and a short spin down to a complete stop.

thanks!

***falcon409*** · January 2nd, 2013, 21:42

Hmmm, I may be wrong, but I believe that's coded as animation in the mdl file.

**bstolle** · January 2nd, 2013, 22:23

Originally Posted by skyhawka4m

Can someone tell me how I can change the length of time the prop spins down to a stop? What I would like to do is have a prop spin down to a complete stop but take a bit longer than a shut down and a short spin down to a complete stop.

Quite a few possibilities here... e.g. by increasing prop inertia in the cfg file, but the 'standard' way is to increase engine shaft friction (table 509) in the airfile. (this has nothing to do with animation)

**skyhawka4m** · January 3rd, 2013, 02:33

what is the prop animation line that I have seen some adding to the aircraft.cfg file for?

**bstolle** · January 3rd, 2013, 03:08

Can you copy & paste an example? Never seen that and it's also not mentioned in the SDK...

***Dangerousdave26*** · January 3rd, 2013, 03:34

I am not sure where it originally came from or why it is in this aircraft.cfg file.

[fltsim.1]
title=Ryan_Navion_260_cherry
sim=260_B_300
model=
panel=
sound=
texture=test
panel_alias =
sound_alias =
kb_checklists=
kb_reference=
atc_id=
atc_id_color=0x00000000
atc_parking_code =
atc_airline=
atc_flight_number=
ui_manufacturer=Ryan
ui_typerole="Single Engine Prop"
ui_type=Navion 260
ui_variation=Cherry
ui_createdby="Larry Green"
prop_anim_ratio = 0.0
description=Ryan Navion 260B
visual_damage=1
atc_heavy=0
atc_id_font=Verdana,-11,1,600,0

**roger-wilco-66** · January 3rd, 2013, 03:44

This might be related to helicopters, the SDK says:

prop_anim_ratio

The ratio of rotor revolutions rendered to the actual revolutions in the simulator.

Bell 206B JetRanger( prop_anim_ratio=-1.76 )

[Edit] no its not soleyly for helos, you seem to be able to make the prop appear to be turning slower than actual RPM

**bstolle** · January 3rd, 2013, 04:32

Interestingly this is in the flightsim_n section. Neither in the prop or rotor section. Nevertheless it wouldn't affect the stopping time of the prop/rotor.

**fleurdelys** · January 3rd, 2013, 04:55

The "prop_anim_ratio=x.x" does not work in FSX for standard propeller engines but does wonders in FS9. Can't say about helicopters as I never fly any but I would be surprised that FSX would have dropped the standard prop engine and retained it for helos only...

But I do remember that there was a line (???) in either the engine section or propeller one, as bstolle suggests that did do something for short stopping propeller rotation ...

Sorry for not being more specific but you might want to check with other propeller driven aircrafts cfg's as some lines are present in different planes and absent in others...
Your best bet might be to look into a cfg of a plane which you know does take longer to stop rotating and see what is different from your own cfg.

Best of luck,

Fleurdelys

**Delta_Whiskey** · January 3rd, 2013, 20:16

i have used .. propeller_moi = xx.x in the propeller section of the aircraft.cfg file with good results
a down side may be the larger spindown time also translates in to longer spool up times

a paper prop verses a granite prop as it were

**fliger747** · January 3rd, 2013, 20:42

OK:

Two main things affect the spindown rate: The 509 table in the .Air file controls the low to RPM cylinder friction. Lowering this value causes the engine to spin down more slowly. The same value may vary with the brand of FSX installed; The prop MOI gives a bit more inertia for higher values.

T