Hi All, 

 

I just did a quick run on the ER and discovers a three issues and hopefully PMDG will be able to have a look at it to make the excellent product to be perfect one. 

 

So what I did was just took off from Macau (VMMC) RWY 34 then make an immediate turn climb to 3000ft to join the ILS07L to Hong Kong (HKG), and I actually did it a couple of times in the last two hours to have a look at the handling aspect of the airplane. And here's what I found.

 

1) Landing Distance

 

   The LDW was 240Tons, with Vapp 151kts, Flaps 30, Autobrake 2, idle Reverse. The real Landing distance assessment tool gave me 9230ft/2813m.

   Weather condition was   15 deg C   Nil wind     dry runway.

   

   however the airplane in FSX, stops half way of the runway even before the 1st high speed exit which has a Landing distance of 6437ft with just Autobrake 2. I touched down at about 1100ft from the threshold.  

 

2) Airplane pitches up at 50'RA with no control input in manual flying.

 

   For some reason, every time at the 50' RA call out, the airplane pitch up about 0.5 to 1 deg. I had to push the nose down every time to prevent it to balloon. I wonder if this is just me or the problem of my yoke, anyone else had similar experience? Apparently this wasnt the case with the 772LR before the SP1 update. On the real airplane, pilots actually need to pull back slightly to hold pitch because of the artificially introduced ground effect.

 

3) Crosswind Landing

 

   I noticed since the 772LR, when landing above 20kts cross wind, after touch down with slight crab angle ( <5 deg ), the airplane will continue to slide to downwind side for a while even after all the main wheels have touched down. This happens when the runway is dry.

 

I understand that the ground friction simulation in FSX isn't very good. Therefore I wonder if this is the main reason for causing issue 1) and 3) above, and hopefully there's a solution to solve this. However if this is the limitation of FSX itself, then its fine. Ever since FSX came out, I dont recall that I had flown one FSX airplane which could simulate correct "touch down --> roll out" action after a landing in a crab angle.  

 

 

Overall, the ER flies very nicely, it handles much like the real airplane now. 

 

have fun everyone

 

 

2) Airplane pitches up at 50'RA with no control input in manual flying.

 

   For some reason, every time at the 50' RA call out, the airplane pitch up about 0.5 to 1 deg. I had to push the nose down every time to prevent it to balloon. I wonder if this is just me or the problem of my yoke, anyone else had similar experience? Apparently this wasnt the case with the 772LR before the SP1 update. On the real airplane, pilots actually need to pull back slightly to hold pitch because of the artificially introduced ground effect.

 

 

 

 

 

I am also experiencing the uncommanded pitch up at 50` RA. Have not tried it with the 200LR or the freighter yet. I am using a Logitech Attack 3 Joystick. 

Okay, I did some testing: The uncommanded pitch up only occurs with the 300, not with the 200LR/F. Anyone else experiencing this? It´s quite annoying, because the whole approach is ruined when you have to push the nose down exactly the moment you´re crossing the threshold  :huh:

You guys need to read the 300ER supplement section in the intro PDF.

It specifically talks about what's different on the 300 including flight characteristics.

You guys need to read the 300ER supplement section in the intro PDF.

It specifically talks about what's different on the 300 including flight characteristics.

 

Thanks for the hint! I read the intro manual and of course I read the SP1 and 300ER supplement sections before I started fying the 300ER.

 

The thing is I can´t find anything about an uncommanded pitch up at 50`RA on every landing. Neither in the 300ER section nor in the SP1 section. There´s actually not much about the flight characteristics in the 300ER section.

 

The only thing I found is rather vague, it´s in the passage about tailstrike avoidance (page0.00.171):

 

Quote: "You will notice a distinct difference in the feel of the 300ER vs. the 200LR/F during takeoff and landing because of the system’s more aggressive control loading." (end of quote)

 

If you could point me to a passage in the intro manual that helps me with the pitch up - problem I would be grateful!

"A note on low weight takeoff trim settings

The 777 (particularly the 200LR) is prone to very nose down takeoff trim settings at low gross weights due to the highly aft (30+%) CG. This is most commonly encountered on short flights with light fuel loads.

FSX’s flight dynamics engine unfortunately has an issue with this type of configuration that will cause the airplane to still feel like it’s out of trim in the nose down direction immediately after takeoff even with the takeoff trim set on the numbers. When the FBW system engages at 100 feet, there can be a noticeable pitch up motion – this is simply the system compensating and correcting for the FSX issue and not any sort of “autotrim” happening. If you find this effect annoying, you can add an extra unit or two of trim to the calculated one at low weights / aft CGs. Even in the real world, anywhere within the green band is acceptable for takeoff, so this isn’t completely out of the realm of realistic anyway."

 

If this doesn't explain what you're experiencing, then it's best to submit a service ticket.

Thanks for that! I have no problem with takeoff, but with landing. B) What I tried is adding some 3 or 4 knots to the approach ref speed. Much better now. 

 

Cheers, Arne

 

 

What I tried is adding some 3 or 4 knots to the approach ref speed.

If you're landing with A/T on, you should be using Vref+5 anyway.

If you're landing with A/T on, you should be using Vref+5 anyway.

Sorry for being unclear, that´s what I do, I added some on top of that 5 knots...

I'm thinking it is related to transition from flight to flare mode; it seems that the wrong reference speed/trim reference is maybe being fed to the FBW causing a pitch up?

 

Best regards,

Robin.

I'm thinking it is related to transition from flight to flare mode; it seems that the wrong reference speed/trim reference is maybe being fed to the FBW causing a pitch up?

 

Best regards,

Robin.

You mean theré´s something on my end I can change? 

Guys, the AP disco issue is being looked at, currently.  A new build is going out with some tweaks attempting to address the issue.  The only problem is that some people are unable to reproduce the issue, so it's tough to pin down.