Sorry to ask this, I have the Honeycomb yoke and using the button/Switch to set my trim it also doesn't work/ or it doesn't move. Is there also a setting in the FMC?? ThnX appreciate it for the help.

52 minutes ago, Whisper202 said:

Sorry to ask this, I have the Honeycomb yoke and using the button/Switch to set my trim it also doesn't work/ or it doesn't move. Is there also a setting in the FMC?? ThnX appreciate it for the help.

Not sure exactly what’s going on but the elevator trim on the 777 works differently to the traditional trim from what I’ve read. Might have something to do with it 

I have default binding for a switch and wheel - elevator trim up and down . For me 777 It works exactly how in any convectional airplane (given your hydraulic operated as expected) . Trim switch down make airplane pitch up, trims switch up makes airplane pitch down. I don't recall any particular FMC setting for that. I transfer my 737 profile to 777 and it works without any modification. 

This should shed some light on the trim on the 777.

 

 

The 777 is a very stable and docile airplane; the PMDG didn't get it right. I see the correct FBW programming, but how their airplane is reacting is wrong. They had issues with the P3D and now with the MSFS. As usual, they have people on their "beta testing" who blame the MSFS limitations. 

That is totally wrong. For example, we have a few Airbuses with more sophisticated FBW systems, and their implementations work very decently. I wished they would snap out of this blaming mentality and realize who's at fault here.

5 hours ago, LRBS said:

This should shed some light on the trim on the 777.

 

 

 

So there is direct input from the pilot via PFC that decides how much trim based on flight profile? In other words it will not refuse to trim but rather decide how much to trim?

1 hour ago, sd_flyer said:

 In other words it will not refuse to trim but rather decide how much to trim?

Your assertion is correct. 

For this particular FBW,  trim switches on the control column send a signal to the flight control system, which then commands the stabilizer to move up/down. As the stabilizer moves, the elevator adjusts to maintain the desired pitch attitude/speed. I don't remember correctly. There is a speed variation where the system keeps the aircraft level for that speed/pitch without the pilot constantly applying pressure to the control column. Basically, it helps prevent inadvertent changes in pitch/speed within certain variations; as soon as those are exceeded, re-trimming is necessary.  This system is very smooth on changes, very subtle, and barely noticeable. Not as they implemented with big and fast pitch movements. I can sometimes see as much as 2 or 3 degrees/sec, which is unrealistic. 

I notice some wild changes when the AP is turned off, at about 1,000 ft, 200 ft or so, and sometimes before the flare. Not realistic at all, the airplane is very stable and smooth!

11 hours ago, LRBS said:

we have a few Airbuses with more sophisticated FBW systems, and their implementations work very decently

There's a big difference that no one is considering: the Airbus FBW system uses passive sidesticks, which work exactly in the same way as almost all our controllers (including Xbox sticks). That's why it's easier to simulate an Airbus FBW and to do it correctly.

With the PMDG 777 (and maybe QW and WT 787), there's an additional complication: the real aircraft has a column in which the neutral position changes based on airspeed. There are controllers with force feedback but FF is not supported in MSFS AFAIK. In older sims, it was possible to replicate this behavior (if you had FSForce), but not so in MSFS. How can the actual 777/787 FBW be replicated in a believable way if the stick/yoke doesn't behave like the actual one? Please remember that this difference is the same one that causes trim in FS to be a lot harder to apply than in real life.

13 hours ago, sd_flyer said:

I have default binding for a switch and wheel - elevator trim up and down

I don't have the MSFS 777. But in P3D, the trim only works if I use the standard controls (Elev Trim Up and Elev Trim Down). Knowing PMDG, it should be the same for MSFS. That's why it worked for you. How did @Whisper202 map his trim buttons?

 

 

 

5 hours ago, LRBS said:

Your assertion is correct. 

For this particular FBW,  trim switches on the control column send a signal to the flight control system, which then commands the stabilizer to move up/down. As the stabilizer moves, the elevator adjusts to maintain the desired pitch attitude/speed. I don't remember correctly. There is a speed variation where the system keeps the aircraft level for that speed/pitch without the pilot constantly applying pressure to the control column. Basically, it helps prevent inadvertent changes in pitch/speed within certain variations; as soon as those are exceeded, re-trimming is necessary.  This system is very smooth on changes, very subtle, and barely noticeable. Not as they implemented with big and fast pitch movements. I can sometimes see as much as 2 or 3 degrees/sec, which is unrealistic. 

I notice some wild changes when the AP is turned off, at about 1,000 ft, 200 ft or so, and sometimes before the flare. Not realistic at all, the airplane is very stable and smooth!

That is interesting, but I absolutely don't feel any difference between flying Fenix 320, Leonardo 88 or PMDG 777. They all feel exactly the same on round up. I do feel however MSFS exaggerated ground effect. but it's true for all aircraft LOL

If the problem is that the switch does not seem to work, make sure that you have your hydraulic pump turned on, without it on sitting at the gate it will not work. In addition, if I remember correctly, when flaps are not extended it is very slow/small movements only, once the flaps are extended it is much easier to trim.  

19 minutes ago, jjeffreys said:

If the problem is that the switch does not seem to work, make sure that you have your hydraulic pump turned on, without it on sitting at the gate it will not work. In addition, if I remember correctly, when flaps are not extended it is very slow/small movements only, once the flaps are extended it is much easier to trim.  

I always set the trim when setting up the flight according to the FMC, and then dial in some down trim on the initial climb out, and never touch it again for the rest of the flight. 

2 hours ago, Luis Hernandez said:

There's a big difference that no one is considering: the Airbus FBW system uses passive sidesticks, which work exactly in the same way as almost all our controllers (including Xbox sticks). That's why it's easier to simulate an Airbus FBW and to do it correctly.

With the PMDG 777 (and maybe QW and WT 787), there's an additional complication: the real aircraft has a column in which the neutral position changes based on airspeed.

I disagree; the process is much simpler. MSFS utilizes electronic signals for both, it's just a matter of correct programming.

 

1 hour ago, Bobsk8 said:

I always set the trim when setting up the flight according to the FMC, and then dial in some down trim on the initial climb out, and never touch it again for the rest of the flight. 

Bob, as you mentioned, you set a trim setting for TO during preflight.  There is no such thing as "that you never touch it again," or "dial in some down during the climb." 

 

CG will constantly change throughout the flight. 

 

Now, when the AP is on, the airplane will adjust the trim automatically.

 

After you disconnect the AP, the airplane will fly for a short time without any pilot/trim inputs. As time passes, you must do something: trim or "fight" with the flight controls to keep it in balance. 

 

Now we have this FBW system or TRIM SPEED, where the electronics maintain that attitude/speed for a certain time and correct for small changes. For example, it will correct for a +/-10 KTS variation or +/10 FT/MIN  change. Those changes vary by flight conditions, approach, takeoff, or cruise.

 

The Boeing 777 is a very stable airplane, but we always use trimming when flying manually, not as much as others do to this system. 

I have one big outstanding issue with 777 autopilot. Sometime it can't tun 90 degrees or more at certain speed. It just overbank and rolls over! 

33 minutes ago, sd_flyer said:

I have one big outstanding issue with 777 autopilot. Sometime it can't tun 90 degrees or more at certain speed. It just overbank and rolls over! 

This happened to me only once; among other outstanding issues, I decided to park it and felt cheated buying this product. It's a pity they released software with so many problems and are now concentrating on working on the freighter version release—the same with the 737, unfinished businesses, and now the initial 777. I don't understand this race of selling broken products. Despite some lovely achievements, they prove that quality and customer service are no longer priorities. They only make broken promises about fixing or upgrading the products. I wonder how much longer they can continue on this road before the word gets out about their new unhealthy practices. I hope it is not too late for PMDG to wake up.

3 minutes ago, LRBS said:

This happened to me only once; among other outstanding issues, I decided to park it and felt cheated buying this product. It's a pity they released software with so many problems and are now concentrating on working on the freighter version release—the same with the 737, unfinished businesses, and now the initial 777. I don't understand this race of selling broken products. Despite some lovely achievements, they prove that quality and customer service are no longer priorities. They only make broken promises about fixing or upgrading the products. I wonder how much longer they can continue on this road before the word gets out about their new unhealthy practices. I hope it is not too late for PMDG to wake up.

I still enjoy flying it though. I go by taking manual control of 777 when necessary. I'm pretty sure they will patch it up eventually