Handling dynamics with redesigned FBW Sytems

[777 340]

Now you can very very simply view the FBW system as a level change autopilot mode (or FLCH if you like), with the target airspeed being set by the trim buttons on the yoke (instead of the MCP speed dial in the case of the automatic flight system). That's all there is to it basically.

That simplified it for me, about to fly my first flight so I will report back.

[martin-w 3,234]

Sure you can both feel and hear the real 777 touchdow.

Less so if it is a greaser ofcource.

 

Have not done a landing yet in the PMDG SP1.....will let you know.

 

 

As it stand right now, I am all over the sky with the way trim works now :-(

I did a take off, retracted the flaps and accelerated to clean speed.

No trim was required almost the whole time (which is not as in real life) untill about 10kt prior to reaching clean speed.

The nose suddenly went up and even full elevator down pressure could not bring the nose down! (also not realistic).

Trim down then rectified the situation.....but boy what a messy take off :-(

 

I already deleted the FSUIPC.ini once......but will do so again, and I will try a flight with basic FSX controller settings (so with FSUIPC off!).

 

It could be my FSUIPC settings.....so no judgement yet, + I also still have to read the new manual (there is something new about controller dead zones in the FMC settings).

Yep brief flight I did yesterday included a very ugly takeoff.

 

At this point I fear its still not right.

 

Reserving judgement untill I can test properly.

[777simmer 117]

I deleted the FSUIPC.ini and this time I used FSX internal controller settings for my controller axis commands. (no FSUIPC).

 

I also recalibrated my controller in Windows.

 

This time the take off was better.

(only had time for one test so by no means a final conclusion on my part)

 

Accelerating and descelerating also required appropriate trim down and trim up to stay level in 4000ft. :-)

 

The only thing I had a hard time with was the final, exact trim setting.

I was close to being in trim, but just could not get that last bit if trim in there that would keep the airplane right where I wanted it (which was level in 4000ft).

If I let go it would, after a second or two, either climb or descend slowly.

That last short touch of the trim switch that should give me the IN-trim situation did not work.

 

So I decided to turn on the FBW trim indication (FMC option).

 

Contrary to what I thought previously, this is actually a great help!

 

I could now see why ,the airplane would keep deviating from 4000ft if I let go of the yoke....because the FBW trim speed was still off by 3kt or so still!

And I also saw that a quick hit of my trim switch did not allways result in an IN-trim situation.

Sometimes the FBW- trim speed would even jump in the wrong direction causing an even larger out of trim situation!

 

Anyway, when the FBW trim speed is displayed on the ND I can get the airplane perfectly in trim.......however, this cheat mode is not available in the real aircraft (not the ones I am familair with at least).

 

So why is it so hard to get that final trim setting, that last little bit, right when FBW trim speed is not displayed??

 

Maybe because we do not have force feedback?......well yes, but I can trim the PMDG737 quite easily (been a while that I tried but I dont remember having such a hard time with that addon) and the 777 should be just as easy!

 

Still testing........

[Swen 1]

 

I could now see why ,the airplane would keep deviating from 4000ft if I let go of the yoke....because the FBW trim speed was still off by 3kt or so still!

And I also saw that a quick hit of my trim switch did not allways result in an IN-trim situation.

Sometimes the FBW- trim speed would even jump in the wrong direction causing an even larger out of trim situation!

 

Look my post above:

 

 

In my speed Tape is activated FBW Trim Speed in blue vector. If i trimm this vector don't go smooth up and down. It's jumping extremely. I don't know if this is right or not. Are my trim settings for my yoke wrong?

 

Nice, exactly what i experience. The trim jump in speed to heavy, you can't set well the trim, But if you on level the trim will catch the speed... It's look like.

[Michael Moe 493]

That simplified it for me, about to fly my first flight so I will report back.

 

So what will i do on approach when i want a certain v/s?

 

Right now and maybe wrong i adjust trim for v/s

and then throttle to maintain speed.

 

Cant trim be used for v/s?

 

Michael

[Swen 1]

Check the Video above to understand how FBW Trim work.

[amidoo 0]

If the trim switch controls the speed, then V/S should be controlled with the throttles, at least this is how I understand it.

[martin-w 3,234]

The trim switch does not "control the speed". It trims just like any other aircraft. It's just that the trim position "relates" to a given speed.

 

The bottom line is that it shouldn't feel any different to trimming any other airliner.

[amidoo 0]

Martin, yes this is what I meant, I did not express myself correctly.

[777simmer 117]

Check the Video above to understand how FBW Trim work.

Your video does not work.

 

In Avsim it will not play at all and I could not find that video anywhere on you tube (but I am not a you Tube pro either to be honest)

 

Do you have a link for the video?

[RudiJG1 172]

Your video does not work.

 

In Avsim it will not play at all and I could not find that video anywhere on you tube (but I am not a you Tube pro either to be honest)

 

Do you have a link for the video?

 

https://www.youtube.com/watch?v=kae_wDCGex0

 

can't you click on the ''Watch on YouTube" option in the lower right corner of the video pane? You access this by clicking on the YouTube label there.

[Swen 1]

He ask of a like, so here it is: https://www.youtube.com/watch?v=kae_wDCGex0

[777simmer 117]

https://www.youtube.com/watch?v=kae_wDCGex0

 

can't you click on the ''Watch on YouTube" option in the lower right corner of the video pane? You access this by clicking on the YouTube label there.

Yes I can.....did not know about that :-)  thanks!

He ask of a like, so here it is: https://www.youtube.com/watch?v=kae_wDCGex0

Thanks.....got it already.

 

Excellent video....only watched the first 2 minutes, but I would be surprised if this guy is going to tell you anything stupid.

[Swen 1]

 

Excellent video....only watched the first 2 minutes, but I would be surprised if this guy is going to tell you anything stupid.

Really?

[777simmer 117]

Ok....I continued to watch, lol

 

 

Do you guys see how easy it is for this pilot to get the EXACT trim reference speed?!

How he kind of feels his way there?!

Push a little, hit the trim switch a tad......wait......push a little again, hit the trim switch again.......wait.............push a little again, hit the trim switch again.......wait.......oh, needs a little tiny bit more pushing, hit the trim switch.....wait...............eh voilla....perfectly balanced, perfectly level!

 

It should be that easy!

 

Now I can do those first 3-4-5 trim inputs on the PMDG777 just fine (for example accelerating from 250kt to 300kt).......but right when accuracy is starting to matter, right at the point where the trim ref speed is getting quite close (within 15kt or so) to the actual speed....that is where I am having difficulty here.

 

That first bit from 250kt to 285kt works just fine.

But then.......that last little bit.......where you have to get trim ref speed from 285kt to 300kt (and imagine the trim ref not being displayed.....so no cheat mode)....it takes me way way too long to get that right.

 

I think I will fly with the trim ref speed (cheat mode) displayed for a while untill I get the hang of this.

 

I am still not sure why the last bit is so difficult to get exactly right....

Maybe it is the way that PMDG reduces elevator effectiveness in proportion of the deviation to trim ref speed to simulate wheel loading/force.

Or maybe I just need to fiddle more with the CTL COLLUMN NULL ZONE setting....(I have tried a bit but see no difference).

 

 

I wonder how this kind of simulation effects force feed back yokes !?

Really?

yes....I meant no sarcasm there :-)