News:

Precision Simulator update 10.175 (29 May 2024) is now available.
Navburo update 13 (23 November 2022) is now available.
NG FMC and More is released.

Main Menu

Pitch rate slower than real B744.

Started by Daehee, Wed, 25 Oct 2017 16:28

Daehee

Dear,

Today, I review with my friend who working in big airlines in Korea. He flown with 747-400 last 10 years.
and now, he is captain and flying with B747-8i.
He also one big fan of FS.

He said, PSX is amazing system but, pitch rate is something different compare with real B744.
rather than, PMDG is more like reality about manual controlling.
Above all, pitch is making late response. when pull/push yoke pitch response is slower than real B744.(about 1 sec)
PMDG is not like PSX. My yoke is from ACE. when I make full push/pull, yoke icon left corner in psx as same response.

I don't have any idea, and I can't find any calibration option about pitch rate.
Please advise to me..

My version is 10.3

Daehee kim.

Gary Oliver

Hardy,

I admit to cheating slightly here....

My joystick program in our Sim inputs 1.35x the actual deflection into PSX to bring our yoke movement and feel in line with the Big Sim, using both Peter, a tape measure and videos as reference.

I await my telling off.

Cheers
G


Hardy Heinlin

In the past 3 years, real 744 pilots have reported PSX pitch rate is OK.

Is there a delay between PSX pitch and external scenery pitch? (Smoothing algorithm?) I always refer to PSX stand-alone.

And are you taking the CG into account? Like on the real aircraft, pitch rate in PSX depends on CG.

Forward CG = Slow response

Aft CG = Fast response



|-|

Daehee

Quote from: Hardy Heinlin on Wed, 25 Oct 2017 17:08
In the past 3 years, real 744 pilots have reported PSX pitch rate is OK.

Is there a delay between PSX pitch and external scenery pitch? (Smoothing algorithm?) I always refer to PSX stand-alone.

And are you taking the CG into account? Like on the real aircraft, pitch rate in PSX depends on CG.

Forward CG = Slow response

Aft CG = Fast response



|-|

In my test, I selected 'CG varies with fuel distribution' and PSX stand alone.(didn't use external scenery such as P3D or XPL)
Tomorrow, I will test to use calculated CG with him

Daehee

Chris Kilroy

I, like Gary, also have the pitch axis in my sim set to about 1.33x based on the feedback of a good friend who flies the 744 for United.

Britjet

To be honest I share the view of the original post.
It is not often that we try a hard pitch down (or up) requiring full elevator (in fact probably never on the real aircraft, so real-world pilots would not be much help here) but I have been doing it many times recently in the BA sim to recover from what you might call "unusual attitudes" when my non-pilot guests don't fly correctly.
Having tried the same thing in PSX I would say that the pitch change with large elevator deflections is too slow.
Strangely enough I was planning to do a quick video of such a recovery this weekend in the BA sim to measure the pitch rate. Of course, as Hardy says, it is very dependant on CG, configuration and airspeed.
I hope it will be an interesting comparison.

Peter

Hardy Heinlin

We discussed this here some years ago, and I made some modifications that made everyone happy.

My request to you all is, please:

1. Refer to the PSX instruments, not to the external scenery (it may have a delay).

2. Refer to CG position (it changes during the flight if the CG slider is greyed out).

3. Refer either to pitch inertia (angular acceleration) or pitch rate (maximum angular velocity).

4. Refer to a specific yoke deflection (yoke in PSX, not USB input axis).

5. Refer either to up or down motion.


Thanks :-)

|-|ardy




Will

I have no information to impart about the real 747, but I will say that I'd love to see a video from Britjet about recovery from upsets! One from in a 777 sim is out there on Youtube, but a 747 and PSX-specific video would be a welcome addition.
Will /Chicago /USA

Daehee

#8
Quote from: Britjet on Wed, 25 Oct 2017 18:56
To be honest I share the view of the original post.
It is not often that we try a hard pitch down (or up) requiring full elevator (in fact probably never on the real aircraft, so real-world pilots would not be much help here) but I have been doing it many times recently in the BA sim to recover from what you might call "unusual attitudes" when my non-pilot guests don't fly correctly.
Having tried the same thing in PSX I would say that the pitch change with large elevator deflections is too slow.
Strangely enough I was planning to do a quick video of such a recovery this weekend in the BA sim to measure the pitch rate. Of course, as Hardy says, it is very dependant on CG, configuration and airspeed.
I hope it will be an interesting comparison.

Peter

Thank you for your kind explanation.
something misunderstanding in my post. Actually, full push/pull is one of test situation. first time when I start review with him, we try to manual approach for landing before 10 miles from runway. draw near runway, need to
control minutely.(I think, your very well know about it because of your real world pilot.)
I input small down elev angle by yoke but there is no response even if status correctly change on EICAS and yoke icon on PSX change as well.
So, more input for down, aircraft is slowly down than it sinks quickly after 1 sec. for recover sinks, we pull yoke, it response after 1 sec with high rate. this situation make to very hard controlling when aircraft on approach by manually.
aircraft is oscillation that elev down >no response > more input for down > sink > pull > 1 sec after high rate up..

In summary, regardless of CG, reaction is very slow when try to initial action for correcting for glide slope.(opinion from my friend)


I really expectation your movie :-)

Best Regards.
Deahee

Daehee

Quote from: Hardy Heinlin on Wed, 25 Oct 2017 19:49
We discussed this here some years ago, and I made some modifications that made everyone happy.

My request to you all is, please:

1. Refer to the PSX instruments, not to the external scenery (it may have a delay).

2. Refer to CG position (it changes during the flight if the CG slider is greyed out).

3. Refer either to pitch inertia (angular acceleration) or pitch rate (maximum angular velocity).

4. Refer to a specific yoke deflection (yoke in PSX, not USB input axis).

5. Refer either to up or down motion.


Thanks :-)

|-|ardy

Hardy, Thank you very much for your kind help.
I will go home at tonight(I'm on UTC +9) and then I will record movie what is your requested.

I bought B747 home cockpit hardware($10000) for reach feeling of real aircraft. So, this is very important thing for me.. please help me. : -)

Best Regards.
Daehee

Daehee

Quote from: Gary Oliver on Wed, 25 Oct 2017 16:51
Hardy,

I admit to cheating slightly here....

My joystick program in our Sim inputs 1.35x the actual deflection into PSX to bring our yoke movement and feel in line with the Big Sim, using both Peter, a tape measure and videos as reference.

I await my telling off.

Cheers
G

Gary,

Which mean is 'inputs 1.35x' value? Is this one of rate value for pitch that is inside java source?
Could I change by my self?

Best Regards.
Daehee

United744

I don't notice input lag, with aircraft pitch response appearing almost immediately (allowing for inertia), closely followed by change in vertical speed from steady state. It certainly doesn't take 1 second to react, but it can take more than 1 second to see the full effect of a pitch change and for it to stabilize again, depending on how large the pitch change is.

@Daehee Kim: Would be interesting to see some photos!

cagarini

#12
Also,

for users with low standard hardware, like me ( TS 16000 desktop joystick ), with very short resolution, and travel, I believe the way it is modelled presently is more adequate.

If it was possible to create a parameter in the Instructor Station to set a factor ( like some of the users with full cockpits do ), that would provide a way around for them, without bringing problems to other.

EDIT: Another detail... What values are you using for "sensitivity" in the Pitch / Roll / Yaw USB axis ? They default to a huge value of 300... I have mine between 8 and 12...

Bastien

#13
Quote from: jcomm on Thu, 26 Oct 2017 16:32
Also,

for users with low standard hardware, like me ( TS 16000 desktop joystick ), with very short resolution, and travel, I believe the way it is modelled presently is more adequate.

If it was possible to create a parameter in the Instructor Station to set a factor ( like some of the users with full cockpits do ), that would provide a way around for them, without bringing problems to other.

EDIT: Another detail... What values are you using for "sensitivity" in the Pitch / Roll / Yaw USB axis ? They default to a huge value of 300... I have mine between 8 and 12...

Hello,
I can't speak about the flight model and pitch rate because it's not my specialty and I'm not real B747 pilot.

But I agree with jcomm, we must take in account the kind of hardware installation used by the people.
It could change the perception and feeling even if simulated flight model is close to the real one.

Currently, I use the simulator on a "simple" desktop computer with "simple" hardware devices like a desktop joystick and rudder pedals. The feeling is pretty good and input response seems good too, no lag here.

Like jcomm, sensitivity input on my axes is less than 20 in PSX.

Best regards
Bastien.

Mark

Quote from: Hardy Heinlin on Wed, 25 Oct 2017 17:08
Is there a delay between PSX pitch and external scenery pitch? (Smoothing algorithm?) I always refer to PSX stand-alone.

To add a data point - ExternalSim doesn't have any smoothing on the pitch axis that would cause a noticeable delay.
Worse case delay is going to be 1, maybe 2 boost frames before angular velocity is seen in Prepar3d.
I may add smoothing later, but no worse than a few boost frames of delay.

I do agree with Hardy's assertion that observations should be based purely on PSX displays in order to make this situation easier otherwise there are too many variables.

Britjet

I don't see a problem with small inputs on approach. It looks ok to me.
I was more thinking of large upset recovery rate..
As Hardy says, it depends on a lot of factors..

Peter.

Hardy Heinlin

Who of the critics are requesting more effectivity for small elevator deflections, and who only for max deflection?

If it's only for max deflection I could increase the higher exponential end only instead of increasing everything linearly.


|-|ardy

cagarini

Quote from: Hardy Heinlin on Fri, 27 Oct 2017 18:05
Who of the critics are requesting more effectivity for small elevator deflections, and who only for max deflection?

If it's only for max deflection I could increase the higher exponential end only instead of increasing everything linearly.


|-|ardy

Personally I prefer it the way it is, but some say they use in their bridge apps a multiplier.

Maybe this multiplier could be na option in the Instructor Station, and each one would apply whatever values better fit for their solutions / hardware ?

Hardy Heinlin

A linear multiplier wastes precious hardware headroom.

Daehee

Hello, guys.

Tomorrow(I'm on UTC+9), I will test again with my friend who is real world 744(748) captain. I will record movie and post it for more discussion.

Anyway, thank you for your attention about this post.

Daehee Kim