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citationX

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Re: citationX

Postby legoboyvdlp » Sun Jan 13, 2019 5:57 pm

You can program the route in the CDU. As far as I know the routemanager altitudes are also respected, as they show up on the CDU flight plan page.
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Re: citationX

Postby SurferTim » Sun Jan 13, 2019 6:08 pm

legoboyvdlp wrote in Sun Jan 13, 2019 5:57 pm:You can program the route in the CDU. As far as I know the routemanager altitudes are also respected, as they show up on the CDU flight plan page.

That's great, but you can write down your altitudes on a piece of paper, then throw that paper out your cockpit window just before you taxi. I was an air traffic controller at Los Angeles ARTCC for 8 years, and 4 years as an instructor. You will get what I tell you. I got used to doing the climb and descent calculations in my head. I know what I need.

But despite that (got that worked out), the landing lights are OUTSTANDING! Gotta use Rembrandt rendering to really appreciate them. :)

Still needs work on the panel lighting for night operations.
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Re: citationX

Postby legoboyvdlp » Sun Jan 13, 2019 6:12 pm

Hmm - not sure, but I think it's lower left, just below the PFD? I think it's beside the fuel switches. Not exactly sure... And I'm not sure if they actually work yet.
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Re: citationX

Postby SurferTim » Sun Jan 13, 2019 7:46 pm

legoboyvdlp wrote in Sun Jan 13, 2019 6:12 pm:Hmm - not sure, but I think it's lower left, just below the PFD? I think it's beside the fuel switches. Not exactly sure... And I'm not sure if they actually work yet.

That switch has no effect. The switch panels are still dark.

Edit: I completed only about half of my flights today. The rest were terminated by a program abort. Flightgear just quit. My version of the CitationX uses about 40% CPU usage on my Intel i7 3.4GHz. This version uses about 75% in normal mode. If I increase the sim speed to 4x, it causes the CPU usage to go above 100%, and the flightgear program will abort. Just FYI.
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Re: citationX

Postby legoboyvdlp » Mon Jan 14, 2019 11:40 am

@V12,

You had aileron input in:

Image


also, the wing would have been stalled, and yasim does not handle stalls gracefully.


I took control just before you started the pitch up and did the same but with opposite aileron, it barrel rolled the other way.

so yes, there definitely is a problem there with stalling - but that's more yasim than the citationx...

and looking at your fgtape, the pitch bug definitely is fixed on your citationx, not sure why you claim it wasn't?
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Re: citationX

Postby V12 » Mon Jan 14, 2019 1:16 pm

OK, thank You for analyze. IMHO, aileron input with value 0.02 is too smal for roll rate more than 180degs in 1 second in all what is heavier than RC toy plane :) When I tested roll rate in standard style - level flight, 200 KIAS, full barel roll was much much slower, than this one with full elevator input.
And pitch bug - do You thinking, that initial pitch speed when I moving yoke from center position to it's extent is 2 or 3 times greater than speed, when I do not moving yoke is OK ? This is common problem on almost all YASIM aircrafts. I know only 1, where this bug doesn't exists - try C-130.
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Re: citationX

Postby legoboyvdlp » Mon Jan 14, 2019 1:40 pm

yep, beyond the flight envelope yasim is not good :(
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Re: citationX

Postby V12 » Mon Jan 14, 2019 4:58 pm

About pitch bug - check moments of the take off, You clearly will see move steering column to back, plane starts rotating and without any next movement of the yoke pitch change speed drop to very low value. Speed of the pitch change is large only in the time of the yoke movement.
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Re: citationX

Postby miguel » Mon Jan 14, 2019 5:15 pm

I speak of the CDU that has the CitationX
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Re: citationX

Postby SurferTim » Mon Jan 14, 2019 5:21 pm

miguel wrote in Mon Jan 14, 2019 5:15 pm:I speak of the CDU that has the CitationX

I've given up on it. I'm back to mine. This crashes flightgear about 75% of the time when I use it with the route manager. It is frustrating to get to the initial approach fix to have the whole thing disappear and leave you at the desktop.
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Re: citationX

Postby V12 » Sun May 19, 2019 10:00 am

Still bad FDM :

Check barell rolls without roll input, this plane fly like RC toy with almost zero weight :(
Please, someone, fix that behaviour, this is very nice and good developed plane.
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Re: citationX

Postby legoboyvdlp » Fri May 31, 2019 5:14 pm

I adjusted some things slightly and removed the barrel roll. The pitch inertia is also reduced. However, the problem is adjusting ballast without affecting center of gravity which must remain about 30%.
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Re: citationX

Postby danielHL » Sat Jun 01, 2019 7:17 pm

I think there will be a fundamental problem simulating this model with Yasim. Geometry-wise it's really an edge case with its more than 30 degree sweep angle. Planes with that much sweep are generally problematic at low speeds and estimating the effects of spanwise flow to simulate them correctly in JSBSim is also not trivial.

At the moment I see the following issues that stand out from Yasim point of view:
- aoa=6 at approach configuration sounds pretty high on the nose
- zero camber of the main wing, really?
- use of the idrag element on main wing
- use of effectiveness on horizontal stabilizer
- hstab has camber of 2? this sounds way too much

solution-wise:
Yasim Lift 174, drag 8.3. Anything far over Lift 100 is considered abnormal in yasim. Lift and drag should be much closer together. Cruise AoA of +2° is also suspicious. Most jets fly nose down at cruise.

During takeoff there was a strange reaction on elevator input. It seems as though the rotating moment is applied instantly and then gently decreases again. Something seems realley wrong with the inertia. I suspect the many surface elements that try to model minute details like vanes and fairings.

Just my 2 cent...

CU
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Re: citationX

Postby legoboyvdlp » Sat Jun 01, 2019 7:34 pm

Thank you for the help regarding that. I've increased the approach speed to a more reasonable 130 knots and adjusted the inertia which seems to have helped. I'll try to (when I find time) fix the issues you mentioned ;)
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