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PMDG 747-400 Engine Starting Problem

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PMDG 747-400 Engine starting problem, during engine start, and after starting engines #1 and #4 with no problem and then when attempting to start #2, (start sequence 1, 4, 2, & 3 as per PMDG) as soon as I put the #2 fuel control switch up I get a audio warring and master caution light. What is out of sequence to cause this?Picture #1 is just after starting #1 & #4 ok and then placing fuel control switch #2 to on (to start) and after the warning, did not start #2 -- I know I can, but?Both APU GEN 1 & 2 were selected when starting #1 & #4, but kicked off when started #1 & #4.

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Hi there:Post up a screenie of your overhead panel and EICAS at this stage and we should be able to tell you with ease.CheersPaulPS - BAW Standard ops are (i beleive) 4,3,2,1 - you could try it that way, but same time, no reason that the PMDG method shouldnt work to my knowledge.... ;)

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I think the sequence is 4,1,3,2, so you dont put too much stress on the struts.according to your pics. apu is on avail, not running, apart from that I dont know,,,, sorry.....

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could you put up a picture of you EICAS with the bleed showing? I see you have one pack on and that could drop your duct pressure. I've been able to start 2 engines at the same time. the 4 engine busses and the 747-400 from what I hear can do this with the auto start protection. If you dont have the autostart available you can only start one at a time due to overtemps, hung starts or engine fires that would require your attention. As for stress on the struts, could you show that to me in a manual? if you think about it, this plane weighs over 850,000 lbs and the engines at idle cannot compare to some of the stress that is placed on those gear struts during a landing. I've always heard of the engines being started in reverse order, 4,3,2,1. I used to fly a Dash 8 turbo prop and we started number 2 first all the time... I now am on a corporate jet and we start the right one first unless we are doing a battery start and then we alternate them to see if there are any hidden electrical gremlins

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Okay:Firstly, you have the APU Avail, but not generating. That will stress the bleed air system, as for the first start, there will be little, if any, air available to get those big old blades moving. Try it again with Ground Power on and the APU Gen1 and Gen2 on. Having said that, you do have the APU bleed on, but i think that the lack of electrical power is going to be an issue.Unless you are somewhere really hot (in which case your cooling should be on OVRD (although i see on your EICAS that its only 15*) you can afford to turn off all the packs for the start, again, its all about the Duct Pressure.Aside from that, i see nothing wrong with the rest of the config. As suggested in the post above, stick up a screenie of your ECS page on the upper Eicas.CheersPaul

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Guy's his duct pressure looks fine, around (32) The only issue he will have with APU and EXT on avail is he will get a brief loss of power to certain systems (loss of PFD ND etc) when the power transfers and this should cause a Alert.He also doesn't seem to have CON Ignition but I have done dual engine starts with the GE's out of Quito without any issues (and this is not a good idea in the real bird) so I don't think it is fully simulated in the 744Rob

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Rob;I do beleive you may have just nailed it for him!Having re-read his original post, the audio alert (not necessarily the EICAS warning) and the master caution is what is causing him to abort the start. CheersPaul

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Hi,It's the start sequence I think that's the issue. I start mine in pairs (4 & 3, then 2 & 1). #4 needs starting first, otherwise I find you get alerts, even though the hydraulics are pressurized using the AUX pump.Best regards,Robin.

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First I would like to thank all of you for your help!!Please let me say this:Every thing I am doing is as per the PMDG 747 manual, I have no doubt I have done it right, as I have reviewed and gone over it many times. The PMDG start sequence is 1,4,2,3 or 1 & 4 and 2 & 3.We can experiment and find a way to do things so as not to get the warning, but then we would not be doing things SOP as per Mr. Boeing, right? I just want to do it the same as in the real world, what ever that is, and that should work. Finding that way is what I would like.The point is that something is out of sequence or wrong with PMDGs manual, that's my guess. If not, then I would like to have an explanation as to what is causing the audio warning and master caution if its normal and why.As far as the APU GEN L & R being off in the picture. . . As you start #1 & #4 the APU GEN L & R are automatically kicked off line, they were on.As for duct pressure, #1 A/C pack is NORMAL and #2 & #3 are off as per PMDG, APU is running with APU bleed on.Thanksagain

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HiThere are many way's to start this aircraft. It all depends on engine type, SOP, Tempreture and what location of the planet you happen to be on. This is something new I picked up today from a 744 engineer (not goin to correct his spelling):)Good luckRob

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Well according to the type rating course it depends who the engine manufacturer was.For the purpose of this start simulation it is important to note that each engine type on the 747-400 has a slightly different set of limitations on the start process. For the GE powered airplane,you should start engines 1 and 4 simultaneously, then start engines 2 and 3 simultaneously.You could, if you husband your duct pressure, start all 4 engines simultaneously, but this is ratherdangerous and places significant strain on the engines during their slow motoring for the start.The Rolls Royce powered airplane can have it

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Right then, i think we are going around in circles here.To get to the bottom of this we are going to have to start at the top...Can you tell us 1. Engine Type2. your EXACT flow from starting FS (9 or X by the way?) to getting the adible alertAttached is a BA Virtual checklist that i have just written based on real world ops for another RB211 operator version. Let me know if that helps any. - Note that in the PUSH / START sequence, it states that Hyd Demand Pump 1____________________AUTOThat should read Hyd Demand Pump 1 to 3________________AUTOEngine start procedure is 4+3, 2+1.CheersPaul

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If it helps any, I am using FS9 with the PW Engines.The flow is per PMDG Manual.I get #1 and #2 started just fine with PMDG start sequence of 1,4,2,3, and like I said as you start #1 & #4 the APU GEN L & R are automatically kicked off line, they were on line to start 1 & 4. Is this right?Thanks Again!

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