CJ4 Community Mod by Working Title Released

[vcarlo 529]

2 minutes ago, ryanbatcund said:

Oh - well they seem to have stuck on in my install

Yes, I had my Elevator and Ailerons set on -50% which still did NOTHING for takeoff.  What I learned to do was set HDG synced and ALT to 5000 with a V/S of 2000 FPM.  As soon as I cleaned up GEAR and FLAPS, I hit AP (on).  This would help slow down the wild ride of wings wagging bag and forth (no matter the winds), but all PAX were still airsick after 45 seconds of flight 🤑

[cwburnett 1,809]

6 minutes ago, CJ1045 said:

Well it is probably my control of the aircraft but my CJ4 (with only this mod in the community folder) seems to want to fly to the stars with AP on. I set an altitude to fly to of 180 but it sails on past 180. I have a full flight plan loaded and on the screens but it does not seem too keen on that either. I have no problem getting the default A320 to follow the flight plan in autopilot.

Can someone give me a five bullet point or similar to go from wheels just lifted off to following the flight plan on autopilot at 18000ft please.

Thanks

CJ

My SOP right now before takeoff is:

1) Turn on the FD

2) Set either HDG mode with runway heading or NAV if following a departure procedure on the autopilot panel

3) Make sure FMS is the selected NAV device in the PFD (There's a NAV button with up/down arrows above the PFD)

4) Set my initial target altitude in with the ALT knob on the autopilot panel (so 10,000 or whatever my initial climb altitude is - or set Cruise altitude if you plan to climb straight to cruise altitude)

5) Set VS target to 2,500 fpm for initial climb and acceleration and engage VS mode.

6) Confirm then in the PFD that AP is off, FD is on, HDG or LNAV mode is engaged and VS is engaged with ASEL indicated

Then you can commence your takeoff, gear up, flaps 0 by 180 kts and reduce power to about N1=90-92 and pitch for 2,500 fpm, then you can continue manually or engage the AP, as your speed approaches 250, increase VS to about 4000 fpm (this will depend on weight). Then you can either manage the climb with VS or once you're STABLE in speed and VS, you can engage FLC.

[Andreas Stangenes 1,628]

Is it possible to mod the airplanes' behaviour at this time? Like the pitchiness, or the stall speeds etc?

[CJ1045 469]

Cool, many thanks 'CW' I will have a go at that. A new learning curve after the A320 but I am up for that. Nice thing is that I can set most of it up before takeoff.

CJ

[MattNischan 3,778]

1 minute ago, Andreas Stangenes said:

Is it possible to mod the airplanes' behaviour at this time? Like the pitchiness, or the stall speeds etc?

We've only made basic flight model adjustments at this time. The engine and climb performance is more in the ballpark, but haven't done a full overhaul of the flight model yet. It's definitely something that is on the roadmap.

[neucoas 82]

11 minutes ago, cwburnett said:

My SOP right now before takeoff is:

1) Turn on the FD

2) Set either HDG mode with runway heading or NAV if following a departure procedure on the autopilot panel

3) Make sure FMS is the selected NAV device in the PFD (There's a NAV button with up/down arrows above the PFD)

4) Set my initial target altitude in with the ALT knob on the autopilot panel (so 10,000 or whatever my initial climb altitude is - or set Cruise altitude if you plan to climb straight to cruise altitude)

5) Set VS target to 2,500 fpm for initial climb and acceleration and engage VS mode.

6) Confirm then in the PFD that AP is off, FD is on, HDG or LNAV mode is engaged and VS is engaged with ASEL indicated

Then you can commence your takeoff, gear up, flaps 0 by 180 kts and reduce power to about N1=90-92 and pitch for 2,500 fpm, then you can continue manually or engage the AP, as your speed approaches 250, increase VS to about 4000 fpm (this will depend on weight). Then you can either manage the climb with VS or once you're STABLE in speed and VS, you can engage FLC.

Thanks for this. I would love you guys if you had the time, to include a Readme with the basic procedures, cruise settings and checklist to fly this wonderful bird :)

[cwburnett 1,809]

5 minutes ago, neucoas said:

Thanks for this. I would love you guys if you had the time, to include a Readme with the basic procedures, cruise settings and checklist to fly this wonderful bird 🙂

SOP documentation and basic procedures and performance planning is under consideration and on the to do list. Along with about 1 million other things 😉

[ahsmatt7 1,199]

4 hours ago, vcarlo said:

I have the exact same issues.  I was hoping it was due to NO Yaw Dampening available in the CJ4, but with the new mod, the YD now turns on fine, BUT NO change in the ERRATIC horrible behavior at takeoff.  I use Thrustmaster TC16000M and the TWCS throttle which works fine on every thing except this TAKE OFF roller coaster ride.

 

I have been doing some fiddling.....I think I found a solution to our issues. 

 

I am basing the following notes on feeling and appearance off of my 4000 hours of jet time is comparably sized jets all the way to jets three times this size. Take my opinions with a grain of salt. haha

BEFORE YOU DO ANYTHING BACKUP THE APPROPRIATE FILES!!!! I wont be responsible for any issues you have from not backing stuff up. 😉

Anyways, go into your default CJ4 folder and find the "flight_model" file. You can open it up with notepad or something.

find the line "pitch_moment_pitch_damping" this value should be -419.something. I changed it to 0.0. When I tested it out. Rotation and overall pitch stability is greatly increased. I can set a pitch and then trim it without having to fight the airplane like I'm on a horse. It actual feels like it has a solid amount of inertia within the pitch axis. I tried this in the tbm and I had the same result. 

Give this a whirl and see what you think!

 

Possible side effects......I haven't flown into any turbulence with this airplane yet, but I did with the tbm after I change the tbm settings and I noticed that turbulence feels more like it should but there isn't a huge pitch response with turbulence as before the change. I think its much more realistic.

[ahsmatt7 1,199]

16 minutes ago, Andreas Stangenes said:

Is it possible to mod the airplanes' behaviour at this time? Like the pitchiness, or the stall speeds etc?

check my newest post. this may solve the pitchiness.

[ahsmatt7 1,199]

4 minutes ago, cwburnett said:

SOP documentation and basic procedures and performance planning is under consideration and on the to do list. Along with about 1 million other things 😉

check my newest post. Let me know you thoughts on the edits I mentioned above to another user. You seem much more educated and wise about these things than me.

[cwburnett 1,809]

1 minute ago, ahsmatt7 said:

I have been doing some fiddling.....I think I found a solution to our issues. 

Matt, I hope you don't mind, I'm placing this into our project board for experimentation. We haven't even begun to look at flight model, so I want to record this for later consideration.

[Flic1 976]

Guys...thanks for this fix!  I really like the CJ4 but it was was just too incomplete to enjoy.  I added this fix and did a quick jump from KPHX to KSAN at sunset.  I just entered a simple direct flight and LNAV worked great!  Power felt much better as well on takeoff and climbout.  It was just a quick, rushed flight and didn't get much more into the details of the FMC other than basic route and throwing my speeds on the tape and it was the best flight I've had so far in any aircraft (including many months of Alpha).  I will try another later on with a more official setup in the FMC (SID's, STARS, APP).  I did notice the issue with the AP starting descent immediately when changing your altitude and had to get on VS quickly.  Wil try enabling VS first on the next flight.  Thanks for the hard work on this and look forward to additional fixes!

[sd_flyer 6,038]

Guys what are power setting for economy cruise? I'm barely making 1000 nm with 30 minute reserve

[FNAL 151]

Just now, sd_flyer said:

Guys what are power setting for economy cruise? I'm barely making 1000 nm with 30 minute reserve

The fuel flow is not perfect right now and it seems to scale linearly with N1 which it should not.  We haven't really messed too much with that yet, most of our focus has been the FMC but it's on our list.

[FNAL 151]

20 minutes ago, ahsmatt7 said:

 

find the line "pitch_moment_pitch_damping" this value should be -419.something. I changed it to 0.0.

This definitely made a difference, I jsut tested it.  Feels a lot more solid but there is still a little bounciness left over.  Perhaps that is deep in the aerodynamics simulation or something that could be rectified from messing with the flight model config I don't know but it's a head start.  I'm sure Asobo will be making flight model changes as well in the future

👍