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Guest ingroundeffect

PMDG 747-400 TIME COMPRESSION PROBLEM

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Guest ingroundeffect

I just purchased the Queen of the Skies package and am very pleased with it...until I enable time compression. When I enable time compression the Auto Throttle will disconnect. In addition to this, engine 3 will randomly flame out...and ONLY engine three everytime. My FMC will also keep alerting me to a message that says "MAX ALT ***" indicating that there is a max alt the plane can reach, even though the VNAV page will tell me that the max alt is well above that. If I do not enable time compression...the plane flies fine. What can I do? I can't fly from Detroit to Osaka in real time! Thanks

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Why not? It's called a "flight simulator". Simulates real life, and in real life you don't have time compression, now do you? Fly a shorter flight...And question about TC: it's normal. PMDG 747 can't run at TC higher than 4x I think, if even it can handle 4x...And sign your post per forums rules please.

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Hi there! PMDG can run at 8x fine according to manual, and does so on my computer (one has to do it every now and again because the FS clock is slow). Incidentally, sometimes funny things happen when selecting something from a menu like save, or time acceleration with the pmdg 747. Sometimes I find the engines all shut down very quickly then come back in about 2-3 seconds, note the EICAS next time you get the max alt message, it is just responding to the strange "engine stopping" phenomenon. All returns to normal in a few seconds, but you do lose some speed!The way around this I find is just to pause before you select anything from a menu, i.e. save or time accel.Hope this helps,Rudy


Rudy Fidao

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Guest ingroundeffect

awesome! will certainly try that. love the product and just really want it to work to the best of it's ability. Thanks again!Josh

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Guest Jock in a Frock

I think this problem has a similar root cause as the problem with loading a pre-saved PMDG flight (i.e. it takes some time for all the FMC / EICAS systems to settle down). The QotS has such a complex and inter-dependant model running behind the FS9 interface that it takes a lot of CPU cycles to keep track of the engine performance and flight dynamics. When you use time compression, you're asking the Queen to skip a whole bunch of computations it needs to realistically model a 747 in flight.You can see a similar effect with the default 737 or 747 (or indeed any default plane with an autopilot). Set up straight & level flight with ALT HOLD engaged on the autopilot, then set time compression to 64x. Soon you will see the plane porpoise through the sky as the flight model tries to keep up with the huge variations in the incoming data. It tends to over-compensate, so climbs and dives around the assigned altitude.A faster PC has less problems keeping up with this. I noticed this after upgrading from an Athlon XP 2400+ to an Athlon 64 3700+Personally I don't time accelerate above 4x in the 747, just to avoid such problems.Andy Scholes

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Guest 737767

I have a similar problem even when just using time acc 2x: the AT don

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Guest ingroundeffect

Hey,I was the first one to report this problem and so far I've found a few things that have helped. Right after I take off I engage LNAV and use the Vertical speed and Auto Throttle to climb to cruise altitude. I do this is in real time, so it's like 10-15 mins but once the plane levels off and you've set the econ cruise speed in the speed window, hit pause, then set 4X and then unpause the game. Anytime you plan to make a change through the menu system hit pause first. The plane does run at 8X, but I find that that speed will creep up if left unchecked. I just stop using VNAV altogether. Hope that helps, 4x is a blessing compared to real time!Josh

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FWIW, I use 4x & 8x compression regularly in my trans-oceanic flights. I use 1x for takeoff, climb, descent, & landing and am almost always in LNAV and VNAV throughout the entire flight. When coming out of warp-speed (compression) I always have to hit the VNAV button again even though it is always illuminated. Look at your PFD throttle Ref (upper left-hand corner) before you do. You'll see that it is blank. As soon as you hit the VNAV button, the throttle-ref re-engages and it syncs back up and the FMS and MCP continue without incident.Hope this helps...


Regards,
Al Jordan
------------
KMLB

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Guest 737767

thanks for your replies! In fact, I fly real time for take off and climb until reaching cruise level, as well as from about 50 nm before TOD point. What I did not used to do is to pause the simulator before engaging 4x compression. And equally to you, I found the throttle ref at the PFD blank.I will try the pause thingy on my next planned long haul from Frankfurt to Seoul and give you a feedback how it works for me.cheersAndreas HermesEDDHhttp://i104.photobucket.com/albums/m191/AHermes/lsd2.jpg[/img]http://www.precisionmanuals.com/images/forum/747400.jpg

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