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mburkhard

MD-11 system depth preview: Electrical trouble!

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Hi all,in another thread someone was not sure about the depth of our MD-11 simulation compared to other fine add-ons out there, so let me show one example.The following sequence shows an 'all generators off' situation, meaning all engine generators are no longer working, for an unknown reason. A situation like that happened on a Qantas B747 some months ago, so don't think this never happens.Note that in such a situation hydraulic pressure is still being generated.So via the PMDG failures menu I select to fail all three engine generators, first only one, than the other two.Note that to handle this situation I can use a real checklist and all happens as indicated on that checklist.http://idisk.mac.com/markus.burkhard/Public/PMDG/demo_0.jpgFirst master caution with an associated message that one engine driven generator is OFF, no problem, the other generators can handle that.http://idisk.mac.com/markus.burkhard/Public/PMDG/demo_1.jpgThe situation displayed on the SD ENG page.http://idisk.mac.com/markus.burkhard/Public/PMDG/demo_2.jpgThen two more generators fail. The only thing left right now is the emergency power and battery power. All screens on the F/O's side are dark, also lost are autopilot, auto thrust and both FMC.Furthermore, engine 2 just flamed out (no suction feed possible, and there's no fuel pump running to get fuel up to the tail.http://idisk.mac.com/markus.burkhard/Public/PMDG/demo_3.jpgHave a look overhead. Note that the indication lights of the AIR, HYD and FUEL panel are all gone, so if you had to push one of their buttons you had no indication of any action.But according procedure the engine ignition is set to override.http://idisk.mac.com/markus.burkhard/Public/PMDG/demo_4.jpgWe need power now, fast! Deploy the ADG, air driven generator. This propeller driven generator may give you either hydraulic pressure OR electrical power. We need the latter.http://idisk.mac.com/markus.burkhard/Public/PMDG/demo_5.jpgTo activate the ADG's electrical mode there's a 'ADG ELEC' pushbutton on the overhead's ELEC panel.http://idisk.mac.com/markus.burkhard/Public/PMDG/demo_6.jpgWe get five of the six DUs back, plus the two MCDUs, and engine two relights because we set the ignition to override earlier and fuel feed is again possible. However FMC1 is lost, you can see that the captain's MCDU dropped to the MENU page giving no FMC prompt.http://idisk.mac.com/markus.burkhard/Public/PMDG/demo_12.jpgFuel is now fed out of tank to up to engine 2, only one pump available as indicated on the SD FUEL page. Note that there's no fuel quantity indication available on this page, indicated by the amber Xs.http://idisk.mac.com/markus.burkhard/Public/PMDG/demo_7.jpgThe ADG is of course visible on the outside model, extended below door 1R and rotating.http://idisk.mac.com/markus.burkhard/Public/PMDG/demo_8.jpgRemains the issue of no FMC on the captain's MCDU and the ND is not showing the map.http://idisk.mac.com/markus.burkhard/Public/PMDG/demo_9.jpgHere's where the SISP panel comes into use. Using this we switch the captain's side to FMS2 by pressing the 'FMS' pushbutton. The procedures calls for the 'APPR' button too. Note that due to lack of power the indication on the switches will not light up when pressing them.http://idisk.mac.com/markus.burkhard/Public/PMDG/demo_10.jpgAs you can see the MCDU1 now shows the FMC2 as available, so now both captain and F/O work on the same FMC.But we got a new message 'FMC RANGE DISAGREE'. This is caused by a different range setting of the F/O's ND (not available anymore). Now since the FMS data comes from the F/O's side which has a range of 10nm on the ND the system can't draw a 40nm range as presently selected on the captain's ND, hence the message.http://idisk.mac.com/markus.burkhard/Public/PMDG/demo_11.jpgSwitching to 10nm on the captain's side gives the MAP indication back and we have the full flight plan visible again.That's it, off to the nearest suitable airport!Hope this gave you a good taste of the complex system simulation available on our MD-11!Best regards,Markus

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Auch! I had a real jawdrop over here, DENTIST!!Stunning shots, and ofcourse simulation.Can't wait!Best regards, Joey

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Hi Markus,great pictures. Thank you very much for your effort, it is appreciated!!Did you land her safely?????Wijnand (EHBK)

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Wijnand,after you have worked through the checklist for this scenario you'll be able to land the aircraft just fine. However at about 100kts during landing you will loose the ADG power as there's not sufficient airspeed then to drive the propeller.I didn't land yesterday, had no time for this, sorry :)Regards,Markus

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I think in terms of 'systems depth' the PMDG MD11 will be considered the 744 PS1.3 of MD11's sims.My MD11 consultant once commented to me that the PMDG MD11 models failure scenarios that even real the MD11 simulators don't model, which is amazing frankly.Bryan

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Hello Markus,As I follow the forum multiple times a day to see how it goes with the MD-11, I couldn't resist to reply, now. As I can see what your aircraft has "onboard", I really do believe why it takes so many time to develope it.My congrats to you and the team, and thank you so much for nice screenshots and explanations.Best regards,PeterBelgiumFlightsimulator is not a simulation, it's a way of life ....

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Amazing!!Thanks for the presentation, very instructive and a good appetizer too :)

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Hi Markus,does the PMDG MD11 simulate a realistic ECON speed (including the wind factor)?Thanks,Holger

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>does the PMDG MD11 simulate a realistic ECON speed (including>the wind factor)?Holger,yes ECON speed calculation as well as all wind entry possibilities are modeled.Regards,Markus

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>During an emergency/battery only situation like this, are the>automatic air/hyd/fuel systems still being run by their>respective controllers or have they reverted to a manual>mode?Lee,if you look at the screenshots closely you will see alerts like 'SEL FUEL SYS MAN', this means that those systems no longer work in automatic mode and if you want to make any changes you need to switch to manual.If you are on EMER and ADG power only there really is not much kept working.Things get worse if you are in an all-engine-out situation. Then the ADG needs to produce hydraulic pressure and can't give you any power. Then you'll have two display units only, no FMC at all. However you can still access the standby flight plan function as long as you have IRS working on battery, this gives you the possibility to enter waypoints as coordinates like in the early days of INS navigation. Fully modeled here of course :)Regards,Markus

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>>does the PMDG MD11 simulate a realistic ECON speed>(including>>the wind factor)?>>Holger,>yes ECON speed calculation as well as all wind entry>possibilities are modeled.>>Regards,>MarkusThank you Markus!Just to be sure. I dont talk about the wind entries in the fmc. I talk about a dynamic ECON SPD, which increases with higher headwind components. Currently I only know the Lenonardo Maddog, which simulate this correctly.Thanks,Holger

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I need a new keyboard - this one is flooded!!! :-lolCOME ON PMDG! RELEASE THIS THING! :DBest regards,Robin.

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In the event of that many failed Generators, would starting APU have been part of that checklist too? This AC looks brilliant! Just trying to pass time w/ the Queen in FSX until MD11 release.WillyOuch! no autopilot and having to go thru all of that. Does this bird diconnect from auto real smooth?

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>>>does the PMDG MD11 simulate a realistic ECON speed>>(including>>>the wind factor)?>>>>Holger,>>yes ECON speed calculation as well as all wind entry>>possibilities are modeled.>>>>Regards,>>Markus>>>Thank you Markus!>>Just to be sure. I dont talk about the wind entries in the>fmc. I talk about a dynamic ECON SPD, which increases with>higher headwind components. Currently I only know the>Lenonardo Maddog, which simulate this correctly.>>>Thanks,>Holger Hi Holger, I don't find any reference in the manual of the leonardo maddog regarding a dynamic ECON SPD. I tried to enter some winds at the legs page, but the ACT ECON CRZ speed stayed where it was. The only thing that changes it directly is the cost index (+ changing acft we

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Hi Jan-Paul,this is not influenced by the fmc directly. You have to monitore your PFD. Watch the MACH Nr. with headwinds and then with tailwinds. When the headwind component increases then also the MACH increases. This is more influenced by the actual wind conditions which you can see on the ND or on the progress page (747).This is especially interesting when you cross the atlantic ocean with 100kts headwind for example.Friendly regards,Holger

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I beg to differ. The wind effect is not simulated anywhere correctly. Abruptly, in a gizmo fashion for simmers that are not really familiar with cost index equations yes. Correctly no... Sorry to break the illusion.As far as the MD11 FMS goes, the ECON speed model has been validated by over 100 prediction vs. measurement data in the real sim. Hope this makes you happy :)Best,Vangelis ===================================== E M V Precision Manuals Development Group www.precisionmanuals.com=====================================

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>In the event of that many failed Generators, would starting>APU have been part of that checklist too?Yes, but it's not that simple. Starting the APU at high level after more than two hours inflight is not recommended in this situation due to heavy battery drainage. And it's not guaranteed that the APU will start above FL250, so you wouldn't want to drain all your battery trying to get the APU started.>Ouch! no autopilot and having to go thru all of that. Does>this bird diconnect from auto real smooth?What do you mean by that? If you disconnect AP in a no wind situation then airplane's pitch and bank would just stay where it was with AP.Regards,Markus

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Hi,I don't quite see the logic here:>> Starting the APU at high level after more than two hours inflight >> is not recommended in this situation due to heavy battery drainage.Getting a couple of gens online has to be better than emergency power any day of the week! ;) >> And it's not guaranteed that the APU will start above FL250So get to FL250, start the APU, get #2 back up, and climb again, using the APU gens for electrical power!Best regards,Robin.

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>Hi,>>I don't quite see the logic here:>>>> Starting the APU at high level after more than two hours>inflight >>> is not recommended in this situation due to heavy battery>drainage.>>Getting a couple of gens online has to be better than>emergency power any day of the week! ;)But what if it doesn't start? Then you've just wasted a huge amount of battery power and then you have an even bigger problem as the battery normally only last for about 30 mins and you may have to rush to get on the ground instead. In this case I will rather stay with what I know I've got than what I may get or could lose.>>> And it's not guaranteed that the APU will start above>FL250>>So get to FL250, start the APU, get #2 back up, and climb>again, using the APU gens for electrical power!Why would you even consider climbing back up? In case I've lost all my main generates it would be an emergency with the associated mayday call and diversion to nearest suitable airfield. Also depending on the apu you may not be able to load it although you can (maybe) start it.Rene

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Let's break this down:You've got 2/3s available thrust that you had before the loss of #2. You might need to start a drift-down procedure.You say you only get 30 mins battery. OK - so you're mid-Atlantic, and 4 hours flight time from the nearest airport. You're going to worry about a 30 minute battery being depleted to get the APU running?>> Why would you even consider climbing back up?Simple - fuel efficiency. I'd need to descend to get the APU running. Once the APU is running, I can get the APU gens online to power the systems, get the fuel pumps running again and can get #2 restarted. The point of 30 mins battery becomes moot once it's powering the systems.I do see your point about the APU failing to start, but if it did, you're stuffed anyway. Once the APU is powering the systems, you're most of the way there.The above are just the core reasons why I'd want the APU started. I'd also be wanting to know why I lost all 3 gens.From the MD-82:LOSS OF BOTH GENSThis emergency condition is indicated by:

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