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Guest jcomm

744 - I can start all engines at once!!!

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Guest jcomm

Even with all PACKS on NORM!!!GREAT!But unrealist no? ;-)Will this get fixed on the upcoming patch?

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Are you 747 systems engineer or pilot? How do you know how the real 747 works? I for one believe PMDG if they modelled it like that, that on the real 747 is exactly like that...

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Didn't try it yet but that's not normal. Maximum 2 engines can be started at the same time with 2 packs selected off.But I think with the autostart sytem you can pull and start all 4 engines at the same time, even with all packs on, but the autostart system automaticaly starts only one then.

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Guest jcomm

Yep!But this one starts all of them! AND ... you can keep ALL PACKS running at the same time!I don't recall if this is one of the "features" to be corrected by the upcoming patch.Thanks for your reply!

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Guest andyman

You're right. It does, Autostart--ONPacks- ALL NORMGround air- OFFAPU/apu air-ONPneumatic Pressure- 23 PSInow Its time to startAutostart-ONAll 4 starters-pulledFuel cutoff switches- turned on in fastest sequenceN2- all engines rise at same rate and have nearly the same value(because of the delay between flipping the cutoff switches)The N2 rose to 12% N2 in about 15 seconds when starting all 4 at once.When starting only one engine with all packs off it still takes 15 seconds to reach 12% N2.HMMM.THe lvl-d takes much longer to spool up if you have one pack running.

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Guest Darren Howie

I am very sure that you can attempt to start 4 engines at once in the real 400 and in fact it may just work.But would you or you just impatient to lose your virtual job.Most companies still do one at a time starts so why would you want to do 4??????????????You can do lots of things in simulators you would never dream of doing in a real aircraft many of which push the limits of its systems.Many of which the aircraft is capable of doing in the real world but at a price to the system.The point is why would the guys patch something that nobody in there right mind would do?I guess they just didnt allow for people who spend there whole life finding ridiculous holes in an excellent addon.IIRC simul start is ok with one pack and max temp of around 41 deg C.Darren

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Guest

maybe it has something to do with the model always having ground power and air. I'm sure it would be possible in real life if you had power and air, otherwise youd put too much of a load on the APU

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Guest andyman

Also you would be risking a hot start or something, if your autostarting, the ""system"" would stop the engine start to protect you. LVLd has made it that you can't start both engines at once because there isn't enough pneumatic pressure.I guess if i had to have one thing to be fixed is the rate at which the engines spool up when you do all 4 at a time compared to 1.

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Guest teeloo

I think simulators are really cool for one thing: do what you normally wouldn't do!Thus pushing the envelope of all systems. See if it works or not.I think it's perfectly ok to try all 4 engines at the same time. If the 744 is really well modeled (ie pneumatics), you should see differences in pressure, rise time etc. Hey maybe even force a hotstart, hungstart or no start. Let's see what the engines can do.After all, good minded people isn't all what the PMDG 744 is build for. The '4-starts-all'people make sure next generation sims do even better in realism:Better engine realism. Local pressure, temperature, dewpoint, winds speed and direction might come along to determine an engine starts succes. ;-)But lets wait first for the other engine types being modeled in the first place ;-)Teeloo

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Guest lbb

"Are you 747 systems engineer or pilot? How do you know how the real 747 works? I for one believe PMDG if they modelled it like that, that on the real 747 is exactly like that..."If that was the case, then why would there be any need for a patch at all? PMDG comes close, but some areas are better than others. I believe the pneumatics system has a few differences to the RW, apart from the one mentioned by JC.- The green flow lines start at the location of the bleed air valve. They should start directly above the number for the engine.- Even with engines off, putting NAI on will show flow lines from the engine to the NAC TAI.- When the lines are pressurized but the packs are off there are no flow lines. This is also true for EXT AIR.- A cross-bleed start from 1 engine is not possible- The hydraulic demand pumps are powered whenever there is any pressure in any duct. So when you close the isolation valves and the engine bleeds on the left side, the left hydraulic demand pump will remain running- On the ground, with all packs off, the EICAS will say the packs are in HIGH FLOW- The CABIN ALT on the upper EICAS will never show amber or red- The CABIN ALT will never show less than zero. This can be seen for instance when closing the outflow valves on the ground.- Also, with outflow valves closed in cruise, the CABIN ALT will show 0, the DeltaP will show 10,5, but there are no warnings of any kind and pack 2 will not shut down.- With both outflow valves on manual, EICAS should say CABIN ALT AUTO, rather than OUTFLOW VLV L and RMind you, I'm not trying to suggest it is badly done! It's just that it is not perfect. And no, I don't expect perfection, but I do like the game "Find the differences" :-)And in case you wonder, no I'm not a pilot, but I do have a number of RW manuals.Leo Bakker

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Guest Foizman

>Even with all PACKS on NORM!!!>>But unrealist no? ;-)Your are absolutely right: this is not real and it might be patched with the V1.03.BUT... is there any force in you that forces you to do that? Both in the - Original_boeing_747_operations_manual(AOM) and the - PMDG747_400_OPERATING_MANUAL_V10 and in the- Mike Ray's The UNOFFICIAL BOEING 747-400 SIMULATOR CHECKRIDE PROCEDURES AND TECHNIQUES MANUAL one can read that this is not possible in real 747s, so: thats it-> DON'T DO IT IN THE SIM BECAUSE ONE CAN'T DO IT IN THE REALWORLD.And if there are speed-pilots which want to use this "feature" because they are e.g. on the lam that's even ok for them, isn't it?Conclusion/my opinion: this correction is not a must for the V1.03greets,Volker

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Guest jcomm

teeloo,I am already using one such sim - PS1! ;-)

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