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Guest Ricardo Sevarant

Engine out FMC CRZ page problem w/747

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Guest Ricardo Sevarant

Hi,In the midst of an engine failure, the PDMG 747 FMC user's guide states the following:"Engine Out Cruise Operation: In the eventof an engine failure in flight, selecting theENG OUT> prompt at 5R will instruct theFMC to provide engine-out speedschedules, performance predictions andflight guidance.In the event that the aircraft is above themaximum engine out altitude at the time ofthe engine failure, the cruise altitude willautomatically be lowered to the engine outmaximum altitude."When I experience an engine failure with both VNAV, LNAV, and autothrottles engaged at normal cruise altitude, I select the Vnav page on the FMC and press the Engine Out SLK. This brings up the E/O CRZ page with max and opt altitudes listed, along with FMC calculated E/O speed. However, I don't get any flight guidance for an FMC E/O driftdown. The cruise altitude is not automatically lowered, even after I lower the MCP altitude to below the max E/O altitude shown on the FMC. Do I need to execute the E/O mod somehow to get the proper driftdown procedure initiated? I don't see a way to do this and the PMDG manual mentions nothing about how to execute an E/O mod. The PDMG manual referenced above also states:"D/D: Drift down is indicated when the FMCbegins a drift down procedure due to enginefailure at high altitude. The D/D mode willremain as the active VNAV cruise mode untilthe maximum engine out altitude has beenreached and the aircraft has leveled out."I never see this happening. Basically, I seem to be selecting the FMC E/O cruise performance page only and am not able to execute the E/O drift down mode properly. I'm so confused and befuddled.

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Guest Jock in a Frock

>I'm so confused and befuddled. Welcome to my world. ;-)Andy Scholes.

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Guest Ricardo Sevarant

Ha! I was befuddled long before I even began to get confused.

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Guest Jock in a Frock

Lol, sorry I can't be of more assistance, but all this big metal is new to me and I'm still trying to get the 747 open with the remote central locking keyfob thingummy-jig. You did get a thingummy-jig with the download version, didn't you? :-PAndy Scholes.

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Guest Ricardo Sevarant

Ok, the realworld 747-400 AOM states the following action after engine failure:"1 Engine Out ModificationCondition: Select the ENG OUT> prompt on the VNAV CRZ page.Result: The FMC creates a modification and displays applicable engine out driftdown (D/D) performance data."I don't get the driftdown data at this stage, only ACT E/O CRZ with max and opt E/O altitudes.The AOM further states:"2 Drift Down ExecutionCondition 1: Set the MCP altitude at or below E/O MAX altitude and execute the FMC modification. This Condition assumes clearance is approved to descend slowly to an non-standard altitude; for example, FL235. Result: The autothrottle advances operating engines to CON thrust. VNAV commands the driftdown and E/O LRC SPD. The E/O MAX altitude becomes the cruise altitude displayed in 1L. VNAV captures the E/O MAX altitude and commands engine out LRC cruise. The descent rate is controlled to a minimum of 300 feet per minute (fpm). Time and distance for the D/D to E/O MAX altitude display at 2R."Alrighty. Well, I set the PMDG 747 MCP altitude at or below max E/O altitude as described above. The execute key on the FMC page never illuminates?! E/O max altitude does not become the cruise altitude displayed in LSK 1L as described above. VNAV simply holds the original all engine cruise altitude, and airspeed decays into the stick shaker regime with the autothrottles engaged. I think the common denominator here is that there is apparently no way to execute the E/O mod in the PMDG sim? Perhaps I'm still doing something wrong but I'll be darned if I can figure it out. Is the actual E/O mod not implemented in the PMDG sim, with the data displayed in the E/O page being simply for reference? The PMDG FMC user's guide seems to indicate that this feature is indeed implemented, but maybe not?Thanks!

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