What about when you do trim for speed Rob?

 

The main issue for me is that the PMDG T7 doesn't at all trim like I believe it should.

 

You said it should trim for speed just like any aircraft and it shouldn't feel any different. It certainly does for me.

What about when you do trim for speed Rob?

 

The main issue for me is that the PMDG T7 doesn't at all trim like I believe it should.

 

You said it should trim for speed just like any aircraft and it shouldn't feel any different. It certainly does for me.

If I do trim, it trims nicely....very fine steps.....but there is definately way way way too little trimming required.

I just relanded in VRMM and going from 300kt to 250kt and later from 250kt to Vref30 required almost no trim.

I trimmed a few times just for you, and that worked just fine....but if I would not have trimmed I would maintain the new speed just as well.

 

This way the aircraft is actually TOO easy to fly!

 

Do you have FSUIPC in there?

EDIT: if you dont and already use FSX own calibration, you do know you can also set the repeat rate right of your joystick trim button?

 

I cut the FSUIPC.dll file out of the Modules folder at which point FSUIPC is uneffective.

I suggest you try that also, and use FSX default control calibration and see if that takes care of you irratic trim behavior.

 

I pasted the FSUIPC.dll somewhere and will insert it back into the Modules folder and see what that does.

Do you have FSUIPC in there?

EDIT: if you dont and already use FSX own calibration, you do know you can also set the repeat rate right of your joystick trim button?

 

 

I have FSUIPC for wind smoothing, don't use it for controllers.

 

That's a good point regarding the repeat rate.

 

I'll mess with it and see what happens.

How are you guys finding the flare?

 

I'm finding no flare required, and that's at VREF without the +5.

 

I expected to have to at least a couple of degrees.

Well, after a few approach and numerous accelerating/decelerating maneuvers, I conclude for today that the plane does not trim as in real life.

 

I added FSUIPC back into it but there is no change of flight control behavior.

 

This PMDG777 is all in all easier to fly even then the real thing.

I get almost no ballooning effect from extending flaps and although the FBW is supposed to trim out those effects, it does not do that completely in real life.

 

 

Despite that, I feel I have to revise my initial statement of this being "the biggest bug of them all"

 

It flies real nice and maneuvers just like the real thing!

Real stable just a little TOO stable.

It is a treat to fly even for someone who knows how the real thing feels.

 

I will try Secondary and Direct mode as well tonight or tomorrow.

It has a built in artificial stability tuned in the FM, just like X-Plane. Feels very strange.

Hi Rob.

 

 

 

I will try Secondary and Direct mode as well tonight or tomorrow.

 

That test somewhat disappointed me even more. May be I'm wrong, but when I was flying in direct mode, it felt just like the same that in normal mode. You can fly form take off to landing without hardly touching the trim switch if you want.

 

Nevertheless, my head is starting to boil and shed smoke . After reading and reading, I'm starting to be very very confused....I internally refuse to think that if it is a bug, the PMDG staff and Beta testers (including the real 777 pilots) would miss such a big one during all the development and betatesting period.....Look:

 

FCOM 9.20.10

 

"When pilot trim inputs are made, the PFCs automatically move the elevators to

achieve the trim change, then move the stabilizer to streamline the elevator.

Stabilizer motion may also automatically occur to streamline the stabilizer and

elevator for thrust and configuration changes."

 

 

From the document TheAvionicsHandbook_Cap_11.pdf Page. 10

 

"When the trim switches are used in flight, the pilot is actually requesting a new referenced trim speed.

The airplane will pitch nose up or nose down, using the elevator surfaces, in response to that reference

airspeed change to achieve that new airspeed. The stabilizer will automatically trim, when necessary,

to offload the elevator surface and allow it to return to its neutral surface when the airplane is in a

trimmed condition."

 

 

Could all of this, in a subconcissious attempt to believe the FBW is correctly simulated that, in spite of all, when you are holding with the column a more o less fixed position (out o trim I mean), and with that position of the column the speed that results is almost reached or within a few knots above or below, the FBW will trim AUTOMATICALLY the stabilizer in order to stramline the elevator, wich is what is looking like an auto-trim to us????

 

 

Tell me what do you think please.

What I understand from that FCOM is that when you use Pitch Trim, the FBW will first move the elevator to get what you asked it, then wth time, it will use the stabilizer, to be able to remove the Elevator deflection, so it's back to neutral again. But it doesn't mean it's AutoTrimming the aircraft. If it is, it's not clearly said in any Boeing Manual. But they have real 777 pilots to assist them, so I also believe it's hard to accept they were going to let such a wrong behavior go unnoticed

What I understand from that FCOM is that when you use Pitch Trim, the FBW will first move the elevator to get what you asked it, then wth time, it will use the stabilizer, to be able to remove the Elevator deflection, so it's back to neutral again. But it doesn't mean it's AutoTrimming the aircraft. If it is, it's not clearly said in any Boeing Manual. But they have real 777 pilots to assist them, so I also believe it's hard to accept they were going to let such a wrong behavior go unnoticed

Maybe it is just not possible to simulate those three modes correctly within FSX.

I can accept that...all I need is for PMDG to say that, and we can all move on.

Hi Rob.

That test somewhat disappointed me even more. May be I'm wrong, but when I was flying in direct mode, it felt just like the same that in normal mode. You can fly form take off to landing without hardly touching the trim switch if you want.

 

I have not had time to try that but that would support the idea of it not being possible to simulate those modes correctly in FSX.

Maybe the idea of those failures is just to work with the checklist a little bit.

Well, I also agree! Simulating Direct Mode is not important for me in this simulation. But I really want to get a proper simulation of the Normal mode of the 777! it's what made me the most want to fly this Addon!

 

I opened a support Ticket for this. What better way to talk to PMDG than straight to their support team?

Hi everyone...

 

I would very very much appreciate if someone from the PMDG staff and/ore some real 777 pilot should say something about this issue.

 

I'm also experiencing this sort of airbus-like auto-trim behaviour, wich I think doesn´t match with what the FCOM is telling about the FBW normal law behaviour.

 

I mean, for example, I take-off without using AFDS, ie, handflying, no autothrottle and no autopilot at all. With the pitch trim adjusted on ground for my weight and CG location, say 2.5 anu in this case. I rotate and go airborne....I stablish 15º nose-up. After a few seconds maintaing 15º, if release de control column, the aircraft is in trim by magic...

 

If now I increase pitch attitude to say 20º nose-up, just the same...after a few seconds maintaining 20º, if I let go the control column to neutral steadily, the aircraft is again more or less in trim by bagic and will maintain that attitude and correspondig airspeed.....and all of this without having made any trimming by myself.

 

I think this is NOT normal....and if I'am/we're doing something wrong, I would appreciate someone would give us an authoritative explanation about this one.

 

Thank you very much in advance.

 

Great explanation!

 

Best regards,

Robin.

Well, I also agree! Simulating Direct Mode is not important for me in this simulation. But I really want to get a proper simulation of the Normal mode of the 777! it's what made me the most want to fly this Addon!

 

I opened a support Ticket for this. What better way to talk to PMDG than straight to their support team?

Yep, good.

I read the last 2 pages now......

 

I agree there is a distinction between the FBW system streamlining the tail plane, and trimming for speed.

 

If the aircraft is in TRIMMED, level flight, with the stick neutral at a constant 250 kts, and I pull up and hold the stick back, the speed will bleed off, but the FBW will trim for the NEW speed WITHOUT the use of the trimmer when the stick is returned to the neutral point. If I now add power to maintain this new (lower) speed, the aircraft is clearly flying a new speed reference. This is NOT how I interpret the documentation.

 

Best regards,

Robin.

I think there is some confusion about what trimmed speed actually means.  I don't know where the idea of maintaining zero vertical speed came into this, but this is repeatedly referred to in posts in this thread.  I haven't had much time to hand fly the 777X due to OOMs but the manual is very clear about how it should operate.

 

In flight the trim sets a trimmed airspeed.  If you trim for zero column force (no control input in the sim) free then that is the trimmed speed.  The aircraft may climb, descend, thrust changed or whatever, if you release the column the aircraft will return to that speed.  If you maintaining some elevator input then the trim won't fight you and if you release the column the speed you are now at does not become the new trimmed speed.

Level flight is referenced merely as a base-line, to demonstrate the aircraft is in constant speed, unaccelerated flight when our hands are off the controls.

 

The issue we are all seeing is that the aircraft DOES trim to the new speed (in the case of a pitch-up where the speed bleeds off before the controls are released to neutral), which is contrary to our understanding of the manual.

 

Please do not confuse the thread. It's confusing enough as it is.

 

Best regards,

Robin.