Hi all,I've been flight simming for about 13 years, vatsimed for a while, but lost one of my computers due to a "flood". I'm planning on getting back online this month, and doing it again, and have been flying the 737's for years, and really enjoy the PMDG products. Well, I finally went to the 747, and am having some difficulty.I prefer to start with a cold and dark cockpit, and since I work days, the majority of my flights are at night. Here's the problem.Once going through the startup procedures, and checklists, I taxi to my assigned runway, everything is great until my wheels leave the ground. It seems that the minute I bring up my landing gear, I get warnings related to everything electrical, hydraulic, and control surfaces. I can't even turn on the cockpit lights in the sim to see what I am doing to correct the issue. Last night, I forgot to shut off the APU after full startup, and had this error as well. Could this be the cause? It seems like everything is exhausted once I lift off, and none of the overides seem to work. I would leave a list of the warning messages I receive, but alas, I'm at work right now, and don't have it with me.I know that the errors are related to Hyd. Pumps, Elec. Gen's, and Bat DSCH MAIN, and BAT DSCH APU. Those are just a few.Thanks!Miklos

>I know that the errors are related to Hyd. Pumps, Elec. Gen's,>and Bat DSCH MAIN, and BAT DSCH APU. Those are just a few.Seems strange that this is only happening when you lift off....If this happens again, look at the overhead panel and look for any yellow warning on the HYD or GEN systems. Is it possible that after startup you didn't get the engine driven hyd pumps and gen online, instead relying on the APU to drive them? Or worse yet, neither the engines nor APU are driving the systems, instead draining the battery. That will certainly give you problems.First four things when entering a C&D cockpit:-BATT push-button ON-STBY PWR selector knob AUTO-BUS TIE push-buttons AUTO-HYD demand switches ALL OFF(I just remember ON-AUTO-AUTO-OFF)I'm fairly certain your problems are a result of procedural error. Let us know what you find!

Found it!Thanks, made me double check, and the APU was running at takeoff, and the APU bleed air was active as well, fixed this, and everything went fine.Miklos:7

I am pretty sure you don't disarm the APU bleed air, you just turn off the APU switch

>I am pretty sure you don't disarm the APU bleed air, you just>turn off the APU switchI concur. That's according the the 744 checklist I have and the PMDG manual. Both say nothing about turning off the APU bleed.

I don't know why though, been watching my Atlas and Polar DVDs closely to learn the procedures, and they keep it on as well.Doesn't that take away bleed air from the engines? Or does the airplane know not to use it?

Following the PMDG checklist, it does stay on, but I don't remember who put it out, but there was a more "user friendly" walkthrough to starting up, and it shows turning off the APU bleed. I did try it out last night again with the APU bleed on, and no problems. don't think it's a bug, just a fluke.Miklos

I think it's just SOP. If you never turn it off, the you only have to remember to turn on the APU (i.e. only a one step process instead of two).