1.01 Modern mode First flight

Post Reply
eiketre
Posts: 248
Joined: 31 Oct 2020, 12:36
Location: Norway

1.01 Modern mode First flight

Post by eiketre »

Thanks for updating the B38M for MSFS2020 to Modern mode.
Here are just a few items I noticed on the first test flight with model 1.01:

You must trim nose down a lot compared to calculated prior to T/O. Probably something about the stations?

Lift-off. The nose suddenly pitches up a lot. Like a rocket (Even with adjusted trim). Very difficult to do a correct TO. suspect this has something to do with msf2020 and not the flight model? In p3d this works very well.

The flap-lift issue has been resolved with modern mode and I have not had issues with spoiler or ailerons that has been reported for the NG.

The flight model feels a bit more “dynamic” in modern mode. Ex. taxi is more like taxing an ATR42 in windy conditions than a b737, but it is nice to have that movements.

A bit trickier to stay on centerline during TO and LDG compared to the real thing :-P

Thanks for great work 😊
Lapi
Posts: 3141
Joined: 26 Nov 2011, 02:00

Re: 1.01 Modern mode First flight

Post by Lapi »

eiketre wrote: 11 Oct 2021, 17:38 You must trim nose down a lot compared to calculated prior to T/O. Probably something about the stations?
It is a sort of MSFS specialty. Jets in MSFS (without exception) use the Asobo FBW, which is anything but a fly-by-wire system, rather a very simplified auto-trim.
Those planes can sort of TO fine, but only due to this auto-trim. If you disable the so called FBW in any of the default jets, they can hardly takeoff and behave horribly.

As the ProSim planes do not use that under MSFS, the TO trim needs to be increased to get a normal TO.
But in case you find this effect too much at your side, you can always open the flight_model.cfg, find the elevator_trim_neutral = 0.55 entry and decrease it to zero. By that your TO trim will be neutral.
Lift-off. The nose suddenly pitches up a lot. Like a rocket (Even with adjusted trim).
It never happens here...
In p3d this works very well.
It doesn't matter. These are two very different sims with very different dynamic engines.
A bit trickier to stay on centerline during TO and LDG compared to the real thing
We have to be happy if it steers at all, as MSFS doesn't have a native steering yet, so rudder does the thing.
As it is connected to the rudder, if you play with the two rudder sensitivity values, you might get it how you like it, but it is highly hardware dependent.
Some folks complained here of weak steering with rudder, some state the opposite...

regards
Lapi
fly_ebos
Posts: 550
Joined: 12 May 2011, 07:49
Location: Leuven, Belgium

Re: 1.01 Modern mode First flight

Post by fly_ebos »

In conclusion, MSFS looks stunning but flies like crap ?


Verzonden vanaf mijn iPhone met Tapatalk Pro
B738M full cockpit, real liners, real FWD+ AFT overhead, FDS MIP, OEM Boeing TQ + CPflight pedestal
P3dv5.1 and Prosim on Gigabyte Aorus Pro Z390, Intel Core i7 9700, 32GB DDR3-2400, Gigabyte RTX3090 Turbo
User avatar
JWS
Posts: 2192
Joined: 18 Feb 2011, 19:24
Location: The Netherlands

Re: 1.01 Modern mode First flight

Post by JWS »

fly_ebos wrote: 12 Oct 2021, 07:09 In conclusion, MSFS looks stunning but flies like crap ?


Verzonden vanaf mijn iPhone met Tapatalk Pro
That seems to sum it up rather nicely.

JWS
eiketre
Posts: 248
Joined: 31 Oct 2020, 12:36
Location: Norway

Re: 1.01 Modern mode First flight

Post by eiketre »

Lapi wrote: 11 Oct 2021, 22:23
Lift-off. The nose suddenly pitches up a lot. Like a rocket (Even with adjusted trim).
It never happens here...
I have to put in som elevator to get lift off, feels like a normal amount.
When the nose starts lifting (and wheels are off ground) i have to push the the yoke forward a lot to control rate.
If i just leave it in nautral it will just continue to pitch up at a high rate.

It feels like the trim is correct for T/O, but changes when airborne.
This issue was also present in legacy mode.

If you do not experince this it have to be something on my system. I will try to test different setting today. If u have any idea it would be great.

Other than this issue i think the flightmodel works very good with msfs2020.


Regards
Sudden81
Posts: 1483
Joined: 31 Mar 2011, 06:07

Re: 1.01 Modern mode First flight

Post by Sudden81 »

eiketre wrote: 12 Oct 2021, 10:04
Lapi wrote: 11 Oct 2021, 22:23
Lift-off. The nose suddenly pitches up a lot. Like a rocket (Even with adjusted trim).
It never happens here...
I have to put in som elevator to get lift off, feels like a normal amount.
When the nose starts lifting (and wheels are off ground) i have to push the the yoke forward a lot to control rate.
If i just leave it in nautral it will just continue to pitch up at a high rate.

It feels like the trim is correct for T/O, but changes when airborne.
This issue was also present in legacy mode.

If you do not experince this it have to be something on my system. I will try to test different setting today. If u have any idea it would be great.

Other than this issue i think the flightmodel works very good with msfs2020.


Regards
MCAS dos not work ;)
Image
Lapi
Posts: 3141
Joined: 26 Nov 2011, 02:00

Re: 1.01 Modern mode First flight

Post by Lapi »

eiketre wrote: 12 Oct 2021, 10:04 When the nose starts lifting (and wheels are off ground) i have to push the the yoke forward a lot to control rate.
If i just leave it in nautral it will just continue to pitch up at a high rate.
It feels like the trim is correct for T/O, but changes when airborne.
Interesting, I've never experienced it here, regardless that: could you do for me a simple test please?

No weather, make your A/C exact 60T gross weight, even weight distribution just as MSFS does it.
Exact N1 of 89 for TO, no FMC, no reduction. FLP-5. Trim 4.7-4.8. No TOGA, manual thr.
Rotate for 9 deg pitch and keep it until AGL is 100ft, then slowly increase pitch to 14 degrees.
Do you still have to apply fwd pressure on the yoke?

THEN:
Climb with exact pitch attitude, until you feel you do not have to apply any pressure, neither FWd nor AFT.
Pause your sim and tell me your IAS, N1 and N2 indications, EGT and Vertical Speed.
Thanks.

regards
Lapi
eiketre
Posts: 248
Joined: 31 Oct 2020, 12:36
Location: Norway

Re: 1.01 Modern mode First flight

Post by eiketre »

Lapi wrote: 12 Oct 2021, 10:32

Interesting, I've never experienced it here, regardless that: could you do for me a simple test please?
Hi
My setup:
FSUIPC mode. All default values in CFG files. Elevator set 0 in ProSim.
Weather preset: Clear with 1013.

Weight set with msfs2020 and scenario done as u described.

Here are my findings and I did the test six times:
I had to pull aprox 40% elevator for lift off. At aprox 5dg pitch up u can hear click sound for airborne. At the same time pitch starts increasing fast and I must push nose down. Aprox 30-50% elevator down.
To have 14 dg pitch up with no pressure on yoke I must trim down to aprox 3.0.

All engines parameters seems normal. (I can do a readout of parameters next test, but i must trim down)

Btw: I have not installed WASM module due fps decrease over time.
UPDATE: Did a new test with WASM module installed. No change.

Regards
eiketre
eiketre
Posts: 248
Joined: 31 Oct 2020, 12:36
Location: Norway

Re: 1.01 Modern mode First flight

Post by eiketre »

Lapi wrote: 12 Oct 2021, 10:32 [
could you do for me a simple test please?

Hi

Here is a video of the test so you can see the parameters.
T/O roll starts at approx 01:10.
At 3000ft I trim forward to 3.0 to get no fwd pressure.
Here is a link: (268mb):
http://ekedal.no/sim/forlapi.mp4


Regards
eiketre
Lapi
Posts: 3141
Joined: 26 Nov 2011, 02:00

Re: 1.01 Modern mode First flight

Post by Lapi »

eiketre wrote: 12 Oct 2021, 16:51 Here is a video of the test so you can see the parameters.
Great, thanks.
I will analyze what I could see and get back to you shortly.

regards
Lapi
Post Reply

Return to “ProSimB38M - Flight Model”