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Guest davidsyd

738 overspeed indication

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Guest davidsyd

Good afternoon all,I have recently added the 738 to the stable and thanks to a few guys (Norman and Andrew) sorted out a few teething problems and all appears ok. I have the livery and the FS9.1 patch, the no CD patch etc.All operations appear normal except for the following,I first manually adjust the fuel weight with the load manager.Then thinking that isnt carried through the programme simulation I have manually adjusted the weight using what is best described as FS2004 weight adjustment..From what I can see it appears ok.I then load the FMC as per the parameters I need.It appears ok and I blast of on a Flaps 5 departure with Takeoff speeds from the charts..I select Gear Up and get the red bricks indicating an overspeed or an extreme underspeed indication (either case red bricks)I have loaded the 700 series aircraft and getno such indication, it only appears when I have the 800 version running. I know the calculated speeds are good but I cant seem to have an aircraft giving me correct speed limitations and conditions on the PFD tape....HELP it is driving me nuts

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to have an aircraft giving me correct speed limitations and conditions on the PFD tape....
The aircraft may very well give you correct speed limitations but your takeoff technique needs significant adjustments. If you weight is relatively light you may need to derate engines and your pitch angle may be too low - both (specially in combination) can cause serious over-speed conditions.But another possibility is here:http://forums1.avsim.net/index.php?showtop...t=#entry1572431

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The aircraft may very well give you correct speed limitations but your takeoff technique needs significant adjustments. If you weight is relatively light you may need to derate engines and your pitch angle may be too low - both (specially in combination) can cause serious over-speed conditions.But another possibility is here:http://forums1.avsim.net/index.php?showtop...t=#entry1572431
Hi,The reply in your other topic may helpNorman

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On a recent late night SAA flight to Cape Town International (FACT) I got a rare jump seat offer after writing a letter to the captain and sending it via the stewardess to the flight deck.I asked how to correctly manage the speed from point of decent to the next waypoint on the FMC, becasue the 737NG is super slippery andover-speeds a lot under the normal FMC decent predictions.I was told that they always begin decent a few miles before the point of decent. They also have a trick where they program the FMCto believe there is a 20 knot tail wind. This apparently helps reduce the speed a lot.Can a 737NG pilot explain exactly how this is done for me on the FMC, as I didn't take detailed notes.RegardsAnthony ReesCape TownSouth Africa

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Hi Anthony,I don't use the VNAV for descend, only the FL CH and correct the speed to about 285kts.And indeed, start the descend about 15nm from ToD.That's what a real NG pilot ever told me. If he's right then I'm right ... :( Hope this helps,

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There are many who do make VNAV work for them, but I prefer to use V/S (not FL CH) and MCP SPD, I use the VNAV verticle indicator and yellow arc (the banana) as tools to adjust V/S.The VNAV treats all altitude constraints as "level off at" rather than "descend through" but with V/S I can pass by the fix within a few feet of the constraint and maintain a nice smooth descent.

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There are many who do make VNAV work for them, but I prefer to use V/S (not FL CH) and MCP SPD, I use the VNAV verticle indicator and yellow arc (the banana) as tools to adjust V/S.
So do I. V/S in the PMDG-737 works like a swissmade watch. Perhaps we would be soon fired for not making idle descents (FLCH) and wasting lots of fuel... :( The only thing to be aware of with V/S is constantly monitoring the speed.Starting descent 15 or 20 miles before TOD is a good idea...but perhaps your ATC's ideas are very different.The idea of cheating the FMC with a false tailwind sounds interesting and worth to give it a try. But, what the IRS will think about it ?
Thanks for that guys.Can anyone tell me how to add a 20knot tail wind into the FMC?Anthony ReesCape TownSouth Africa
Descent page > Forecast. You can write up to three altitude/wind direction entries.

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Thanks for that guys.Can anyone tell me how to add a 20knot tail wind into the FMC?Anthony ReesCape TownSouth Africa
That would be in the Descent Forecast page. I typically put in winds aloft for the mid 20k, FL180, and 10k. I've never tried adding a correction, as the 737NG does fine on the descents once it gets below about FL370 or so.I DO start my descent earlier than T/D if I'm above FL370. 4nm/1000' above FL370. Add 1 NM per 50kts T/W. VNAV can overspeed you if you're not paying attention.

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Maybe I have a different version of the Load Manager:I set up in the LM the passenger configuration and cargo distribution so it fall just below the maximum zero fuel weight. In FS I set up the fuel used to comply with the trip (including extras like holding, alternate, taxi, etc.) using a third party planner) insuring the CG and total weight comply within the maximum shown.I do have a passenger full load factor but even at 70% I'm sure it would comply.Auto Throttle and the MCP setting I use of 200 initially keep it within the limits while in the airport pattern. I notice TOGA puts an N1 mode speed of about 220 in the MCP speed window. I turn on CMD about 1,000 feet AGL to engage my conservative preset speed and heading following the flaps schedule limits shown on the PFD speed tape before I get in the overspeed condition.Be sure you set on the takeoff page your V1, V2 speeds as the last item after setting up the environment (surface weather, expected runway, and fuel load) so you have the correct guidance.The flight control management system should keep you from overspeeding either you following the guidance for pitch on the FD or engage CMD so it follows automatically. If I use VNAV it is in later stages of flight.While noise abatement may be a consideration, generally for safety (altitude is your friend) an initial speedy V/S is desired.

Good afternoon all,-------------snip---------------I first manually adjust the fuel weight with the load manager.Then thinking that isnt carried through the programme simulation I have manually adjusted the weight using what is best described as FS2004 weight adjustment..From what I can see it appears ok.I then load the FMC as per the parameters I need.

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The aircraft may very well give you correct speed limitations but your takeoff technique needs significant adjustments. If you weight is relatively light you may need to derate engines and your pitch angle may be too low - both (specially in combination) can cause serious over-speed conditions.But another possibility is here:http://forums1.avsim.net/index.php?showtop...t=#entry1572431
I have had problems with the other "possibility" twice. The first time happened when I first installed the 800-900 models. I would take off and the bars would show up and the airplane would try to decelerate to 0kts. The problem was the spd/rest was displaying "0" instead of showing the speed for the flap setting; this only happened with the 800-900 models. I emailed PMDG they told to me to run the removal tool and reinstall as the repair did not work.The second time it happened was a month ago when I reinstalled my 737's (deja vu'). I didn't notice it until I installed all of the paints and out of the frustraion of that and the spoilers not deploying (different thread) I decided to uninstall it and wait for the new NG when it comes out for FS9.Basically I fixed it the first time by using the removal tool and then re-installing. After doing that, program the FMC and then before leaving the gate check the spd/rest under the VNAV page and look at what's next to it. If it says "0" then the problem remains, if it says a speed you're good. Besides, the MD-11 is getting all of the attention now; it's my favorite. :(

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Guest davidsyd

Got to say huys am happy with the amount of support, thank you all!However I am yet to fix the problem.For those new to my hassles, I managed to get the 738 runnig and operating until the point of gear retract. I would then get the red bricks on the PFS indicating an over /underspeed. I got as far as the removal tool and applied that and it changed nothing. I then rechecked that the same thing didnt occur with the 737 600/700, which it doesnt. I then reinstalled FS9 and the pdmg products to no avail. I am a pilot by profession not a computer expert. Candidly I never had an issue with the 744 when I downloaded it, however the 738 has me stumped at this point.Fortunately I am away with work otherwise I may well have kicked the computer at home into submission!Any ideas welcome!!

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Are you using Vista?The file gauges.ini contains sections for each variant and provides the key speeds for display on the speed tape. It is possible that the 800/900 upgrade installer was unable to modify the file to include the speeds for those models. Vista (and Windows 7) have different levels of security to prevent unauthorized modification of files by belligerant software, and it is a pain the the hinny sometimes. Make sure sure assign admin rights to the pmdg folder, and run the installations with admin permissions. Hope this helps.OBTW you can open the guages.ini file with any text editor and see for yourself what is going on in there.

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Dan,No, I'm currently running XP 32 bit.I have noticed though that if I have the 747 installed first it does it, but it seems to be intermittent; sometimes the 737 loads fine other times not so much. Also, it only affects the 800-900 models as I never had a problem with the 600-700 even if I installed them after the 747, 747F, MD-11.I know Ryan mentioned that if the latest installer is used the order won't matter but as stated above I will see this problem intermittently if I install my 800-900 after the 747.Another thing that bothered me was after running the removal tool it got rid of my folders/load managers (in the PMDG folder) for all the rest of my PMDG fleet to include my flight plans. I was able to reload the load managers by doing a repair for the other aircraft and the flightplans weren't a big deal because I always make them with FSbuild before each flight. I just found this to be strange.

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Guest davidsyd

Thanks Dan,Im using XP.I return home tomorrow and I am going to delete it all and start again.I am also going to reformat the whole machine and start from a known base.I will check the ini files before i do it and see what they look like.D

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Guest davidsyd

:( Success!!Thank you to all for their assistance. It seems a combination of things need to be done in the correct order1. Uninstall PDMG and FS92. Reinstall FS93. Update to FS9.1 the later build.4. Reinstall PDMG 7445. Reinstall PDMG 7386. Update PDMG 738 from website support downloads.7. Change resolution for the correct functioning of FMC keypad8. Add liveriesHaving completed these steps add whatever you wish for the running of your simulation.Thanks again to all :( :(

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Guest davidsyd

Hi guys,the thing has been running fine, although noticed a few issues popping up.1. When in the FMC route page and modifying route information, I select an aid to track to in route page 2 and as when the desired aid comes up with lat/long info it has some characters in the background flashing.....2. No overspeed clackers or stick shaker heard when either high or low on speed!!Thanks again guys..all help appreicated..for the record the earlier posts regarding managing a descent, the aircraft does when heavy and high tend to overspeed in the decent phase, when trying to use VNAV.The solution at my employer is to use the descent now on the FMC descent page to go a little earlier and preserve your manouevre margin :(

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