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Guest malcolmt

Normal Procedures Question

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Guest malcolmt

Hi againHere's my scenario:I've stepped inside the cold and dark cockpit of my PMDG 737-700. I decide (my first assumption being this is the correct thing to do) to follow the Normal Procedures (per the AOM) chronologically from "Exterior Safety Inspection" onwards.However, my cockpit has been left by another newbie like me ;) from a previous flight, with one or two switches in "unexpected" positions. For example, the STANDY POWER switch is left with the Guard UP.Nevertheless, I do not notice this and continue on with my normal procedures. Soon I reach BATTERY SWITCH "ON". Result, no battery power and the rest of the procedure does not work, e.g. I can't get the APU to start.Of course, I have since discovered that the incorrect position of the STANDBY POWER switch to be the cause of my predicament (my second assumption now being that I am right on this, but of course I stand to be corrected ?!), and had this been in the Gaurd DOWN position when I climbed into the cockpit, my procedure would have progressed as normal.My question is (at last!!) :) Why doesn't the Normal Procedure prevent this from occuring? Should not one of the first things when you enter the cockpit be to check all the important switches are in their correct positions if subsequent procedures depend on this and, therefore, shouldn't this be built into the procedure?Or, am I mis-interpreting the purpose of a Normal Procedure sequence altogether, and that maybe real pilots rely on their experience to handle these things? I notice that further on in the normal procedure (ELECTRICAL SYSTEM) that the STANDY POWER switch is checked, but for my purpose this is too late !!Thanks for reading !!Malcolm

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Guest cliff

Malcolm a good question asked in a clear and easy to follow manner.I'm afraid I can't answer you but look I too look foward to the the answer from one of our more experienced MembersCliff

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Hi guysI am working from memory so may not have all the facts 100% correct but here goes. I bought the 737-600/700 when it first came out and it was version 1.0. and the normal procedures was correct to the word as the Power Standby switch was in its proper guarded position and "on". however i think we then had an update to software which then become version 1.1, then when I bought the 737-800/900 series and that in turn was updated I believe that also made some changes to the 600 series, so somewhere along the update route the Power Standby changed from guarded on to unguarded off. So the manual was perfectly correct when it was written, its just that the switch position was over written in the update procedure. Thats as best as my memory goes, unless someone knows betterhave fun with the best add ons in the fleetJohn CallejaBAW 0352BA Virtual


John Calleja

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Guest _sebastian_

Hi Malcolm.>Of course, I have since discovered that the incorrect position>of the STANDBY POWER switch to be the cause of my predicamentI doubt that. The standby power switch need not be switched to ON in order for the APU to start, neither on the real thing nor on PMDG's. What might be sim related however is the fact that with the standby power switch turned OFF, the APU GEN OFF BUS light will not light up when the APU generator is ready to give power to the AC transfer bus. This is quite odd considering that 1) you can see the EGT needle drop (because the APU is running) and 2) you can actually transfer power to the AC transfer bus by moving the APU GEN switches to ON as usual. This can be verified by observing the BAT DISCHARGE light turning off. It seems that the only impact NOT turning the standby power switch to ON has is that the APU's GEN OFF BUS lights never light up. My experience is that the APU will start with E-V-E-R-Y-T-H-I-N-G turned off but the main battery switch.>My question is (at last!!) :) Why doesn't the Normal Procedure>prevent this from occuring? I cannot give you an answer to why the checklist does not reflect this unruly behaviour by the aircraft, but I can more or less guarantee you that your problem with starting up the APU does not come from adhering to it. Try the procedure again (with the above remarks in mind) and see if the APU does not in fact start.Regards,Sebastian

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Guest malcolmt

Thanks for the help folks.I'd still like some input from the real pilots if possible please.Cheers !Malcolm

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>>However, my cockpit has been left by another newbie like me ;)>from a previous flight, with one or two switches in>"unexpected" positions. For example, the STANDY POWER switch>is left with the Guard UP.>Having the gaurd up is one thing but what position was the switch in? BAT, OFF, AUTO? Under normal circumstances, the gaurd is always down and the switch in the AUTO position. The only problem you could have is if the Standby Power switch was in the BAT position in which case you could have drained your battery before starting the APU as the battery would be powering the AC and DC Standby Buses. With your battery drained the APU will not start. To preclude this problem make sure you have Extend battery life checked in FSUIPC or make sure the guard is always down with the switch in AUTO.Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.precisionmanuals.com/images/forum/ng_driver.jpg

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Guest kame

Hi John,I tried fresh reinstallations with PMDG_737_THE_NEXT_GENERATION_V1-3.EXE -> PMDG_737_800_900.EXE -> PMDG_737_800_800_Service Update_1.EXE -> PMDG_737_800_900_Model_Update.EXE.At the Cold and Dark start, I have confirmed that STANDBY POWER Switch has changed from guarded on to ungarded off right after Service Update_1.Sincerely,Kan-ichiro Fushihara

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Guest canyonblue737

>Thanks for the help folks.>>I'd still like some input from the real pilots if possible>please.>>Cheers !>>Malcolmfirst in regards to the standby power switch it should never be in anything but guarded and auto unless doing a standby power test or in he event the abnormal checklists call for it. because of this most company AOMs don't show putting it in Auto/guarded as part of any flow. Now of course the current revision of PMDG has it up, and we have to live with that. as for real life thinking when it comes to checking switch positions... experience and knowledge working with the airplane are assumed to help fix any problems you might come across because switches are out of their normal position. for example if you turn the battery switch on and the standby power switch was not in auto then there would be a variety of unexpected results from turning the battery switch on that would lead the pilot to investigate the cause and quickly determine it is the standby power switch's misposition that was leading to the problem.yes we check switch positions and will verify everything prior to going but written checklists and flows can't account for every possible error in previous crews/maintenance switch positions so experience must do the rest.

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