PMDG 737 FMC question

**jeteye99** · 03-05-2011, 04:30 PM

Does anyone know how to change to engine rating in the FMC? I am having a problem that the engines only spool up to 93% power which is not enough to get me off the ground at my home airport of SNA. I know the real planes take off usually by taxiway hotel to eco. How do I make the engines work harder??

Thanks

Eran

**mgh** · 03-05-2011, 04:35 PM

I suggest you ask the official PMDG support forum here

http://forum.avsim.net/forum/136-the...support-forum/

I suspect the cause is not engine thrust but aircraft weight.

**ronzie** · 03-05-2011, 05:56 PM

For SNA the real world procedure is parking brake on, hit the TOGA button (hot spot is the left hand upper screw neat the A/T switch on the MCP for PMDG) for max N1, let it run up to 93% and release the parking brake, which has more holding power than your toe brakes. Climb to 500 or 700 AGL, lower the nose and retract gear reducing power for a noise abatement climb and cleaning up flaps when fast enough as indicated on the speed tape.

Unless you are overloaded for that runway length exceeding MTOW where you start to roll 5700 feet for 19R or 1L is plenty of room. Be sure your init-ref parameters on the FMC are correct for performance. Similar runway lengths exist in Chicago Midway as well. In extremely hot weather or the runway is coated with precip sometimes passenger/cargo load is restricted or flights are delayed for cooler weather.

**jeteye99** · 03-07-2011, 02:17 AM

I fly out of SNA in real life so I know the noise abatement procedure. It is not too safe according to some of the airline pilots. Heck of a lot of fun to do. Usually we rotate by taxiway hotel or so and lift off somewhere between Hotel and Eco. With the sim engine thrust set at 93% (and probably full weight), I cannot lift off till past the end of 19R. So what you are saying is that I am too heavy for take off? Is there any way to tell the FMC to go to 96%N1 or higher? BTW Thanks for the info re the placement of the TOGA button. Never knew where it was so thanks.

**ronzie** · 03-07-2011, 11:37 PM

In your PMDG folder under FS, open folder 737TNG. Under that there are two documentation folders, one for the 600-700 and one for the 800-900. The one for the 800-900 is later and may contain performance take-off data for all four models. -- It does, just checked. Open the take-off performance pdf manual in the 800-900 folder.

You'll find various tables for each model for minimum runway length based on altitude, temperature (density altititude), and take-off weight in addition to maximum available thrust for the environment.