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Wulf190
August 11th, 2009, 11:08
Is it in the airfile or the aircraft.cfg file?

Rami
August 11th, 2009, 11:59
Are we talking propeller pitch or RPMs? Propeller pitch is controlled through engine commands.

Wulf190
August 11th, 2009, 12:52
I have noticed that on Ivan's I-16 Type 29 and Type 28 (Type 27) that the propeller pitch does not change when I use the control I have assigned to in on my X-52, but it worked fine in his others like Ivan's I-16 Type 18.

bearcat241
August 12th, 2009, 02:40
Compare the record 510 of the air files. It determines propeller parameters.

Wulf190
August 13th, 2009, 10:19
Well I used AIRed and did what Bearcat recommended. And I found that the prop MOI for the Type 29 was set to 33.37, the same goes for the Type 28 (27) and Type 24. All of which are having the same issue of not responding to prop control changes. I entered in 22.50 from the Type 18 which does not have the issue, but no change.

I found part of the problem. Turns out the prop pitch works if the RPMs are set to 3000 and can be reduced to 2600rpm, but thats incorrect for any I-16. The Engine that was mounted in them produced takeoff power at 2200-2300 RPM.

bearcat241
August 13th, 2009, 11:27
With regard to record 510 and your problem, i think your points of focus in comparisons should be pitch max/min and fixed pitch blade angle. MOI is just dead prop inertia. It controls "windmilling" at startup and after shutdown.

Wulf190
August 13th, 2009, 11:33
pitch min/max are the same.

The fixed pitch in the type 18 is 22.2, while in the type 29 its 22.5.

bearcat241
August 13th, 2009, 12:00
Not much difference there at all. OK, copy/paste records 506-512 from the Type 18 to all the others. This will ensure that they all have identical propeller data in the air files, while maintaining different engine data specific to each model.

Wulf190
August 13th, 2009, 12:16
Not much difference there at all. OK, copy/paste records 506-512 from the Type 18 to all the others. This will ensure that they all have identical propeller data in the air files, while maintaining different engine data specific to each model.


No joy.:isadizzy:

bearcat241
August 13th, 2009, 12:28
Time to replace the problem air files with the air from the type 18. There must be a hidden entry somewhere in the soup that we're overlooking. I don't know anything about the performance and airframe differences between the I-16 variants, but based on my limited knowledge here i would hazard a guess that they all shared the same basic airframe, propeller and flight control dimensions, with the only real differences being in powerplants and armament maybe. So, if you put the type 18 air in the types 28 and 29, then boosted the engine parameters and perhaps the weight accordingly, you should get what you're looking for in all the models.

Wulf190
August 13th, 2009, 12:35
That would make scense, but there is an issue I found.

I found that if I increased engine rpm to 3000rpm, then prop pitch works... kinda. It only drops the rpms to 2600 when the control is set for full low rpm.

on the I-16 type 24-29 the engine produced 1100hp at 2300rpm, and the prop could be lowered to 1400rpm. I put these entries in even the type 18's airfile, and the prop pitch fails to work. The RPM indication is right, but the prop acts like it is a fixed pitch prop.

bearcat241
August 13th, 2009, 15:47
As much as we love her, we can't expect perfection from the merger of a $35 retail PC flight sim and a separately-created freeware addon. There's just gonna be some minor holes in the FDE programming, either in the sim itself or in the original construction of the addon's air file, where we have to suck it up and roll on. On the flip side, there are some other retail sims out there that don't even permit advanced engine management in their programming, so at least we get a little taste of the real thing, if not perfect.

Do your swaps and get back to happy flights :icon29:...

CheerZ!