Hand Flying

[Britjet]

I think it is about rate, yes.
The roll effect seems to be ground related.
I'm mindful that we spent a lot of time on getting the roll rate correct for engine failure scenarios before, but these could be re-tested later?

[Hardy Heinlin]

Since you and Bode just refer to the flare phase -- and not to E/O scenarios -- I will link the reduction of the induced roll rate with the intensity of the ground effect, i.e. the reduction will increase gradually with the ground proximity to a maximum of 50 %. Outside the ground effect there will be no change.

[Bluestar]

Since you and Bode just refer to the flare phase -- and not to E/O scenarios -- I will link the reduction of the induced roll rate with the intensity of the ground effect, i.e. the reduction will increase gradually with the ground proximity to a maximum of 50 %. Outside the ground effect there will be no change.

Another way for me to express this is "not enough dampening in the roll channel while in ground effect."

Another issue is landing with not enough forward inertia when landing in a crab.  The aircraft tends to follow the crab angle on touchdown as opposed to the direction of flight.   

[Hardy Heinlin]

Another issue is landing with not enough forward inertia when landing in a crab.  The aircraft tends to follow the crab angle on touchdown as opposed to the direction of flight.   

The tire friction behaviour depends on the runway condition: dry, wet, ice. Actually, I developped an update some years ago that makes the aircraft decrab on its own during touchdown due to forward inertia combined with the fact that the body gear is located behind the yaw axis, i.e. when the body gear touches down left of the runway centerline while the nose is right of the centerline, the body gear touchdown will cause a yaw momentum to the left. Peter assisted me in the tuning of this effect, and we also used 744 videos for comparison. I think is effect is perfectly modelled. This effect may be more noticeable on the 744 than on the 737. So I wouldn't use the 737 here as a reference. In other words: I would say the opposite is true: PSX tends to follow the tracked centerline and not the crab angle.

[Panos Bilios]

Hi

this is one of the best crosswind videos, its a 747- 8 thought
and still quite hard to see the bank angle, but the feeling is
that is not banking too much while taking out the crab.

https://www.youtube.com/watch?v=g_X1FARyF9k

Panos

[Hardy Heinlin]

He's applying opposite aileron while pushing the rudder.

[Panos Bilios]

Hi

After testing many times the 20 knot crosswind scenario
I can derive the following: It seems that at a given crosswind
and runway conditions, and according to your rudder hardware
(I have a old set but correctly  calibrated) you need always the same
amount of deflection to eliminate the crab angle, say 20% of full
deflection, keep the wings level with aileron into the wind, you get
always very little amount of bank angle , the jet settles nicely in
the centerline every single time. Now if you press the rudder 40% of
full deflection you still eliminate the crab but you develop a much
steeper bank angle and you need more aileron into the wind, but the landing
ends up more unstable and harder to track the centerline.
So it seems more of a landing technik given your hardware than anything else
I hope I made myself understood

Panos

[Mawea]

Hi Hardy,

I quite like the flight model — I hooked up my joystick and flew a few visual patterns, ILS approaches and some engine failures.

Overall I would say, since you rework the model, the pitch axis is too stable, roll axis is too agile. Pitch would change if not in trim - letting go of the yoke would end in climb or descent, and if changing power settings would be more noticeable.

The nose-down moment after idle in the flare feels natural.

Crosswind landings are definitely a challenge for me without motion and real controls! I still need some practice there —no issues in the real world, but the lack of motion is definitely noticeable. Roll axis after aligning with the RWY in the flare doesn't seem to be too much with rudder inputs. Also during T/O and Landing roll the ailerons feel responsive and good modeled.

 Cheers

* Edit: didn't check my elevator settings!

[Hardy Heinlin]

Hi Mawea,

thanks for your feedback (also via mail). So in your opinion the pitch in PSX is too stable in relation to thrust changes. That's the opposite of Peter's opinion :-) I guess I'll keep the current compromise.

Regarding the nose-down trend after touchdown: There you think the nose-down trend is too strong even with extended spoilers. Peter, would you agree?

Do you guys notice the difference in PSX between spoilers-out and spoilers-in during nose-lowering after touchdown?

Now to something important re Dutch Roll during a crosswind flare: Are you guys sure you're evaluating the inertia of the PSX model and not the inertia of the scenery screen interface?


Regards,

|-|ardy

[Britjet]

Hardy - re nose-down trend too much in flare - agree.
In my case thus would be before touchdown, the pitch-power couple.

[Mawea]

Yes, i recognized the difference with spoilers, switched HYD 4 off to test the nose up moment wasn't sure if that was included but expected it somehow!

Let me have a look at my elevator settings again. Are you guys using a specific curve or default straight line? Think my joystick has no curve etc

[Hardy Heinlin]

For the nose-down test you need no manual control input. Just stabilize the aircraft in level flight using the A/P and the A/T. Then disconnect the A/T and the A/P. Set idle thrust with the mouse or the "5" key (upper row). Watch the rate of the nose-down motion.

[SwissMark]

Hi Alex,

Trust by now you passed your check-ride on the QOTS - congratulations t4 should be well in order.
Do you have any more insights into your IRL experience hand flying the QOTS and the way you modified your settings within PSX? Sincerely would appreciate a IRL Pilot feedback on the topic you raised ...

Have a wonderful weekend everyone and best wishes

Mark

[Hardy Heinlin]

That pitch rate modification and that roll rate modification are now available in PSX update 10.182:

https://aerowinx.com/board/index.php/topic,4191.0.html


|-|ardy

[Mawea]

Hi Hardy,
congratulations on the new modifications! Just did four visual patterns and it feels like the real bird as far as I can say using my TM 1600 joystick. BTW I found my USB elevator ratio at -20% which might explain my request for a less stable pitch axis?! It is set now to +16% which feels good. Roll axis feels more stable which is very nice, had no issues and after the flare the nose down moment *feels realistic (edit)

   

Do you have any more insights into your IRL experience hand flying the QOTS and the way you modified your settings within PSX? Sincerely would appreciate a IRL Pilot feedback on the topic you raised ...

Hi Mark,
no changes in settings for a regular joystick, except USB elevator ratio (to +16%) in the "Basic" section. Don't have a yoke to give advise there, but more than 10 years of flying the Queen.
Cheers

[Britjet]

Thanks as always Hardy. I'll fly it out later today.

[Britjet]

Several approaches flown - the tendency for the nose to lower with power reduction in the flare now feels much more normal. My landings have improved!

I've now flown out several approaches with varying crosswinds, up to 40 knots.
Much nicer - I always had to wrestle with the roll before, now it feels entirely manageable.

Hardy, in my humble opinion, no need for any tweaks - I think you've nailed it!

(Tip - for those trying big crosswinds now, it's worth watching how the autopilot handles the last 500 feet, depending on the wind strength. Pull up the STATUS page and you will see the AP puts in a little bit of opposite rudder at the same time as it starts to lower the upwind wing a touch - all modeled in PSX - of course!)

[Hardy Heinlin]

Hi Mawea and Peter,

glad to hear :-) Thank you!


Cheers,

|-|ardy

[Bluestar]

Hi Mawea and Peter,

glad to hear :-) Thank you!


Cheers,

|-|ardy

Hardy,

The roll channel is much better. 

Thanks,

[Cbf]

Thank's Hardy for this update. And thank's to all experts in the topic for their tips.
Flares and crosswind landings are easier.
As my joystick is a TM 1600, I set the elevator bias to +16% instead of +5% (Thank's Mawea!).