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Von Target

BTW: FLIGHT's engine and CS/Variable pitch Prop model no good either...

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Yesterday I started the day by replying to a thread where, at some point, innacuracies in the xplane10 prop model (CS or variable pitch) was discussed, and I pointed out that if xplane doesn't model the fact that, on a CS Prop, if flying, say, at cruise, 75% throttle (so not full MP ), and you pull the Prop lever back, MP should rise. If you push the Prop lever, MP should, instead, lower.Correct operation is allways: Prop 1st, Throttle 2nd when increasing, Throttle 1st Pro 2nd when decreasing... to avoid engine overstress/damage...I wasn't near my FLIGHT computer, and I do not have xplane installed, but today I was able to test it jsut to find that, FLIGHT is also wrong in this particular aspect :-(And, BTW: since I keep complaining about that exhagerated roll instead of yaw moment in xplane's prop aircraft, I should say that after doing extensive tests with FLIGHT, with my eyes wide oppen!!!, my findings are that although the roll moment is not as pronounced as in xplane10, it is still there where more yaw moment should be, and the yaw moment is also rather faint, too faint to be realistic...BTW: more testing went on with stalls and spins... While FLIGHT is better than FSX, it is still no good in this area either, and at least not better than xplane ...I had to post this, for the sake of honesty....The big difference here is, even if erratic and temperamental, we can hope that Austin fixes it in the future... regarding FLIGHT, I do not really believe it will ever get fixed....P.S.: This same post is now at AVSIM's FLIGHT Forum.

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Interesting post. I decided to test this to see for myself in the DC-3 I made.Here is what I found.I have 4 screenshots. Two of the engine RPM and Manifold Pressure gauges. One showing the throttles at 75% power and the prop levers at full forward and the other one with throttles at 75% power and prop levers pulled back slightly.The other two screenshots are close ups of the before and after effects of the prop levers on the manifold pressure gauge.Only the prop levers were pulled back. Throttle levers were completely untouched.First, the engine instruments showing engine RPM and MP with prop levers full forward and throttles at 75%. Engine RPM's reading 2400RPM and MP just slightly below 41".http://dl.dropbox.co...%28Floats_3.pngAnd the close-up of the MP.http://dl.dropbox.co...DC-3_before.pngAnd then the engine displays after the prop levers were pulled back. Engine RPM at approx 2200RPM and MP just slightly over 41"http://dl.dropbox.co...%28Floats_4.pngand the close-up of the MP gauge. (Not the slight increase of approximately 0.5" to 1" of MP.)http://dl.dropbox.co..._DC-3-after.pngSo, as you can see, based on the charts and doc's I have on the DC-3, what you are saying is, in fact, displaying correctly in XP10. At least in this aircraft.

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Yes, and BTW - Great panel!!!!! ;-)Thx for the feedback Goran !

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And not only in this plane. As a non real-world pilot I only learned about this effect because of X-Plane. Maybe there was some temporary bug in version 10?

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I know Jan (IXEG technical advisor) documented this to Austin in January and he promised to look into it.Sounds like it is fixed then :( M

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Yes, and BTW - Great panel!!!!! ;-)Thx for the feedback Goran !
Hey Goran, don't torture us with that DC-3 you are making :( It's going to be a winner!Alex

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Yep, actually so good that something really weird could happen one of these days.... Go figure.... Fighting/FLIGHTing myself right now... Huh!

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And... could some kind soul please remind me of the link to that freeware Archer III ?Thx!

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Hey Goran, don't torture us with that DC-3 you are making :lol:Alex
I don't mean to. :(
Oh how I want that dc3!!!Rob
Patience, Rob. :( It'll be out sooner than you think.

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Come on Goran, You're KILLING us. :biggrin:And its probably on purpose too. :(

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Just tried with the default B58 (v10.04r3)S.L. to 10000ft max MP is always 29.92 ?!? MP between 20.00 and 29.92 is always the same regardless if the prop RPM is 2700 or 1800. ?!?@GoranI don't see any reason why I should apologize openly in the forum to you (as you demanded your the PM) due to my 'lack of knowledge'@MortonAs posted in the deleted thread, I did find some important and significant improvements in the latest x-plane 10 versions which definitely prove that x-plane is superior in certain aerodynamic areas compared to FSX.Well worth a more detailed look now! Looking forward pm'ing you with detailed questions if you don't mind :(

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I don't mean to. ^_^Patience, Rob. :( It'll be out sooner than you think.
Can't wait!! :)

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Just tried with the default B58 (v10.04r3)S.L. to 10000ft max MP is always 29.92 ?!? MP between 20.00 and 29.92 is always the same regardless if the prop RPM is 2700 or 1800. ?!?@GoranI don't see any reason why I should apologize openly in the forum to you (as you demanded your the PM) due to my 'lack of knowledge'
I demanded?I said...and I quote..."Would love to see your input on this topic. http://forum.avsim.n...no-good-either/Seeing as you are considered a flight model author in the FSX world and you originally said it doesn't work in X Plane, and then disagreed and "laughed" at my definition of what the prop lever does, I'm definitely interested in your opinion.Or, considering you falsely determined that I didn't know what I was talking about, you could follow jcomm's lead and apologize. You can do it in private if you wish. No need to do it in the public forum. Jcomm was a man about it and even PM'ed me afterwards to apologize further."That is word for word, my PM to you. Completely unedited.I preferred to keep it private, but if you want to put it in the open, I'm all for it!By all means, please show me where I "demanded" anything from you.Instead of worrying about PM's (and lying about what I said), perhaps you could worry about how prop levers work.Just a thought.EDIT: Apologies to the rest of the good folks here for this somewhat ridiculous argument I'm having with Bernt. I DID take it private and kept it civil, but he wants to take it public and *personal attack* about what was said. I've said my piece. Again, I apologize!

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Come on Goran, You're KILLING us. :biggrin:And its probably on purpose too. :(
Soon. Very, very soon.Trust me.

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he wants to take it public and lie about what was said.
:( nicely evading the discussion about these basic bugs I mentioned by going off topic (as usual) and *personal attack*

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:( nicely evading the discussion about these basic bugs I mentioned by going off topic (as usual) and calling me a liar...
Well, Iam not surprised ifg all you try are the default planes. In general I would declare them Junk, but this has nothing to do with the flight model in X-plane. I am just glad that I got X-Plane when Carenado had their sale. FSX had bad planes and so does X-Plane.

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Great input Longranger! Just tried the Carenado F33 and MP decay with altitude and response to RPM change works as it should!The problem is that only very few people will try the demo and buy a commercial add on just for testing...

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I did :-), to check the "no yaw moment or almost none/too much roll and or roll right on throttle reduction" bug on prop aircraft....I strongly hope this also gets fixed some day :-)I usualy come back to my ELITE v8.3 to check some parameters... Even if the visuals are poor, it's very accurate in terms of performance of the included aircraft, a lot in the Premium version I bought in 2006 :-)FLIGHT is good/better than FSX in some aspects, but the MP bug is irritating me ... I am a picky guy... :-|

Great input Longranger! Just tried the Carenado F33 and MP decay with altitude and response to RPM change works as it should!The problem is that only very few people will try the demo and buy a commercial add on just for testing...

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:( nicely evading the discussion about these basic bugs I mentioned by going off topic (as usual)
On the contrary. Instead of evading the discussion, in the very next post after the OP, I took it much further with more than sufficient evidence that it works correctly,I'm surprised you didn't see it.

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@GoranI don't see any reason why I should apologize openly in the forum to you (as you demanded your the PM) due to my 'lack of knowledge'
Am I missing something or was this matter completely private until this post was made? At any rate -- let's keep this discussion back in the PM if possible gentlemen. This rather interesting discussion doesn't need any blemishes :(

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Great input Longranger! Just tried the Carenado F33 and MP decay with altitude and response to RPM change works as it should!The problem is that only very few people will try the demo and buy a commercial add on just for testing...
default C90 seems to model it correctly, too. at least I had the impression yesterday when flying it, but I did not observe it very closely. you may want to test yourself.

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