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Guest Chief Wiggum

Missed approach: bug?

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Hi guys. I was practicing some go-arounds today and noticed that when I press TO/GA button (expecting 160kts speed, Vref30 was 140kts), FD bars lead me to 174kts speed. Now I ask you: Ain't I supposed to maintain Vref30+20 until flap retraction speed? Why did my PMDG chose speed 174, that is above the "15" in the speed tape?Am I doing something wrong, or this is really a bug?Note: I tried this with 3000LBs of fuel on both wing tanks and 0LBs in the center tank. Vref15+20 is less than 174, either. I was flying the -800 at KSEA, and used Flap 30 for this approach. All V2+20 speeds on takeoff were below 174, and my ZFW is 124.8x1000LBs.Hope you can help meThanks,

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I am not expert here in regards to mss app F/D display, but do know that you should select flaps 15 and hold VREF + 15-25. Maybe different SOPs have a slightly different range, I am not sure. But this VREF certainly cannot be more than flaps up speed. So I guess the real question should be "what is the F/D showing pitch for when you perform a missed approach? It's true the F/D on a TOGA TO shows V2 + 20 automatically. Maybe a pilot or someone with greater knowledge in this area can help us out.Best Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

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Yes, I do exactly this: flap 15 and gear up afeter I have a positive climb rate. My problem is that the initial climb speed seems to be too high.

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Here is a little bit from the FCTM.http://forums.avsim.net/user_files/85740.jpg So am I right in understanding that the pitch displayed is for the current flap target speed position? So "initial" pitch commanded is for Go- Around attitude (15 degree pitch) then transitions (as climb increases) to current flap speed. Well this is what I believe the above is saying.Best Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

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From A POH I Have...GO-AROUND PROCEDURESGENERALA go-around will be initiated if:

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I just noticed that no matter how heavy I am my MCP speed is 174 (Vref was 148).

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Hey, I'm glad this issue came back. I thought it might be corrected one day but never pushed it. After all this is just very good entertainment software simulation and not an airline training device.The PMDG 737 is the best on the market though in my opionion but if we're going to bring up some minor flaws and I say minor then I would have to agree with you strongly on this. The airplanes just doesn't fly a correct target airspeed during a TO/GA go-around.Here my two cents worth,During a Autopilot or Flight Director go-around, after pushing TO/GA, command speed automaticly increases to maneuvering airspeed for the existing flap posistion. Basicly what happens is the TO/GA command airspeed bug should remain very close to where your Vref 30 or 40 bug was for landing when TO/GA was pushed. Floyd

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Like I said I am no expert and there does appear to be some issue here. But I will state that the F/D does not "stay around" a certain speed as the FCTM clearly states. Initinal pitch @ 15 degree followed by current flap speed. So this is what we need to see corrected although I seriously doubt it will hold up the comming patch..Best Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

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I agree and would like to see it corrected some day. For an Autopilot or Flight Director Go AroundAfter pushing the TO/GA FD target pitch is initially 15 degrees until climb rate is 1000-2000fpm. Then pitch command changes to hold maneuvering speed for selected flaps at max weight.Floyd

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