The Ultimate PSS 777 FDE Tweak

[roevans88 0]

I just merged a posky 772ER with the PSS panel using your 772er FDE file and ran some tests with the aircraft. Two things I noticed were that with a TOW of 450LBS using climb 2 thrust the aircraft reached its acceleration height of 3000 feet and was unable to climb until I selected climb 1. Now I realize that climb 2 is not usually used but with a lightly loaded aircraft I figured it would still be able to climb at least a little bit. The second issue I had was when performing a takeoff at near max gross weight of 655000 lbs and trim set to 6.25. I selected max takeoff thrust which gave me a v2 speed of 165, I cant quite remember v1, and vr but seemed to be about 157, and 160 respectively. Regardless the aircraft did not rotate at v2. Im curious maybe the fmc gave the wrong takeoff speeds or is there something else that needs to be adjusted. Anyway just thought Id share my results hopefully they give some good insight on some of the minor issues

[Johan_Dees 84]

Look in the PSS forum here for another tweak by me. It also has a nice FLCH climb and descend.

[Jack 0]

Hey just tested it again at VREF30+5 and its fine like you say, I must have set the ZFW weight or somthing wrong that would explain the pitch being high.Any ideas on how to change the power requirements on the ground?

[twasono 3]

@roevans88:

with a TOW of 450LBS using climb 2 thrust the aircraft reached its acceleration height of 3000 feet and was unable to climb until I selected climb 1. Now I realize that climb 2 is not usually used but with a lightly loaded aircraft I figured it would still be able to climb at least a little bit.

May be it is caused by the usage of reduced climb thrust (CLB-2). But I think it is come from the limitation of PSS panel itself which was originally designed for 777-200LR.BTW. For 777-200ER model, you should see "Boeing 777-200LR" instead of "Boeing 777-300ER" on FMC IDENT section.Make sure you put "PSS Boeing 777-200LR" string in the beginning of "title" parameter in Aircraft.cfg

The second issue I had was when performing a takeoff at near max gross weight of 655000 lbs and trim set to 6.25. I selected max takeoff thrust which gave me a v2 speed of 165, I cant quite remember v1, and vr but seemed to be about 157, and 160 respectively. Regardless the aircraft did not rotate at v2.

What value did you set for the CG% value? I tried with CG=21, flaps=15 and got the value for trim=7.25. During takeoff, the aircraft can lift off at V2 smoothly.@Jack:Glad to hear that you could managed the pitch during approach. :)About the idle thrust while taxiing, are you sure about that? I though this characteristic is only possessed by A320... :)I've search and read about this issue on A320, they said that the problem is in FS surface limitation. CMIIWBest Regards.

[roevans88 0]

"BTW. For 777-200ER model, you should see "Boeing 777-200LR" instead of "Boeing 777-300ER" on FMC IDENT section.Make sure you put "PSS Boeing 777-200LR" string in the beginning of "title" parameter in Aircraft.cfg"Ah I just went back and checked and it said on the fmc that the model is the 777-300er, details, details. The cg value I used 25% given by using the 200 LR model on the load manager, which although its not the ER it should be somewhat accurate don't you think? How did you compute your cg numbers?Ill do some more testing and let you know what I find

[Nandan Patel 10]

Look in the PSS forum here for another tweak by me. It also has a nice FLCH climb and descend.

What does the autopilot thing do in your update?

[Jack 0]

"BTW. For 777-200ER model, you should see "Boeing 777-200LR" instead of "Boeing 777-300ER" on FMC IDENT section.Make sure you put "PSS Boeing 777-200LR" string in the beginning of "title" parameter in Aircraft.cfg"

Yea my FMC also displays 300ER, can you change that? can you also change the engine type?

@Jack:Glad to hear that you could managed the pitch during approach. :)About the idle thrust while taxiing, are you sure about that? I though this characteristic is only possessed by A320... :)I've search and read about this issue on A320, they said that the problem is in FS surface limitation. CMIIW

Yes im more than sure about that it, im more than happy to fix it myself it myself if you can tell me what I need and a little advice on how to do it?ThanksJack

[twasono 3]

Hi,Just follow the title parameter of aircraft.cfg from this tweak package.For -200, -200ER, and -200LR models, make sure you put "PSS Boeing 777-200LR" string in the beginning of "title" parameter in Aircraft.cfgFor -300, and -300ER, make sure you put "PSS Boeing 777-300ER" string in the beginning of "title" parameter in Aircraft.cfgThis is mandatory, because the PSS panel needs it to determine which code will be used for the FMC.Please find below the examples of parameters:1. Example for -200 model:

[fltsim.0]title=PSS Boeing 777-200LR|200 RR Cathay Pacificsim=PSSB772...

2. Example for -200ER model:

[fltsim.0]title=PSS Boeing 777-200LR|200ER RR Singapore Airlinessim=PSSB772ER...

3. Example for -200LR model:

[fltsim.0]title=PSS Boeing 777-200LR|200LR Qatar Airwayssim=PSSB772LR...

4. Example for -300 model:

[fltsim.0]title=PSS Boeing 777-300ER|300 RR Cathay Pacificsim=PSSB773...

5. Example for -300ER model:

[fltsim.0]title=PSS Boeing 777-300ER|300ER Cathay Pacificsim=PSSB773ER...

Best Regards.

[Nandan Patel 10]

Where in aired is the input for thrusts? I.e. I want to know where the input for thrust at idle is (setting for how much thrust the aircraft produces at idle)Like to know.Thx

[waly87 0]

Hi Twasono.First off all thank you for your FDE update. Its great, Ive spent so long trying to sort out the drag with the PSS air file, the 777 is a slippery aircraft but not that slippery.How ever ther are a couple of things I want to know if I can change?, and if so how?1. The aircraft has a very nose high pitch in all stages of flight. Down the ILS its sitting with about 5* nose up, should be about 2.5*. Could this be changed by adjusting the lift scale or is it its CG that need to be changed?2. Alot of power is required to get the aircraft moving on the ground, in the real aircraft if you are light the aircraft will move under idle power power on the ground, heavey we use abit of power to get it moving, as a general rule take one throttle and move halfway up the opposite throttle then bring level. (Have no idea how to edit this).Everything else is good, fuel flow was abit on the light side but I have adjusted that allready and the trent895 has 93400lbs trust which I have also changed.It would be great if you could let me know how to change those items.Oh and Im using your 200ER.RegardsJack

[Nandan Patel 10]

Who was that replying too sir?

[Richard99_Photography 2]

I am trying just right now, but I must say this tweak is not so good for me at the moment. I don't know if due to winds aloft, but the autothrottle is absolute mad, the throttle power continues to increase, decrease, increase and then decrease, this behaviour during last 3,5 hours. TAS was everything than constant while cruising, the pitch went up, down, up, down... I am absolute drunk for all these aicraft movements. Tomorrow I will try without any kind of wind aloft, but I think I will return ASAP to the PSS model...

[waly87 0]

Hi Twasono.First off all thank you for your FDE update. Its great, Ive spent so long trying to sort out the drag with the PSS air file, the 777 is a slippery aircraft but not that slippery.How ever ther are a couple of things I want to know if I can change?, and if so how?1. The aircraft has a very nose high pitch in all stages of flight. Down the ILS its sitting with about 5* nose up, should be about 2.5*. Could this be changed by adjusting the lift scale or is it its CG that need to be changed?2. Alot of power is required to get the aircraft moving on the ground, in the real aircraft if you are light the aircraft will move under idle power power on the ground, heavey we use abit of power to get it moving, as a general rule take one throttle and move halfway up the opposite throttle then bring level. (Have no idea how to edit this).Everything else is good, fuel flow was abit on the light side but I have adjusted that allready and the trent895 has 93400lbs trust which I have also changed.It would be great if you could let me know how to change those items.Oh and Im using your 200ER.RegardsJack

Hello,First of all thank you to twasono for the files, flown them and they are awesome.Though i did also notice the fuel consumption of the 77L and 77W were on the low side and i was wondering what values you tweaked yours to, to get much closer to the accurate value?Cheers.

[Jure 36]

Hello,First of all thank you to twasono for the files, flown them and they are awesome.Though i did also notice the fuel consumption of the 77L and 77W were on the low side and i was wondering what values you tweaked yours to, to get much closer to the accurate value?Cheers.

Hi, I noticed the same. Been fiddling & flying with the T7 for the whole week. I made a long flight yesterday, WSSS-KORD, distance 8,541nm, B777-200LR. Fuel consumption was 293,000lbs, which seems low for almost an 18 hour trip. For a 15 hour trip some 305,000lbs of fuel is usually burned (RL data) aboard a -200LR. I did use accelerated time, up to 16x! Maybe that's the reason? On a side note, I reduced the elevator trim effectiveness from 3 to 2 without ill effects (I don't do autoland - what's the point, LOL) and I can trim the T7 nicely now...One way or another I like these tweaks a lot, so thanks again, Tri! :smile:Regards,Jure

[Clutch Cargo 384]

Hey Tri,Tried your merge. Looks great however I am experiencing an issue that happens with all my merge attempts. I cannot get the glass displays to light up at night (or dusk). Works fine in 2D panel just not VC. I must be doing something wrong or I have misplaced something. Clutch