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Janov

My observations after first test-flight, post-patch (longish story mode)

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Hi All, I have just done my first test flight, from Warszawa to Frankfurt (EPWA-EDDF), and first off, I was amazed how much closer to reality this already superb simulation had become. I am certainly hoping for further service-updates, and in case they are coming, I hope that my observations will help in ironing out the remaining quirks. I am aware that some observations might stem from special configurations that my airline has - I also didnt try to reproduce each quirk I found, I just write down what happened during the flight that seemed different from the real aircraft. So here it goes:During pushback I started the engines. There seemed to be no sound for them at first, I think that has been discussed elsewhere. While they ARE barely audible at first, there is a certain revving up sound, especially after lightup (Minor issue).When completing the "after start items" I noticed that the outboard ailerons didnt move during the flight-control-check. I never noticed before, because we used to do the flight-control-check after flaps were lowered for take-off, but this procedure has been changed lately. Anyway, it looks like aileron lockout was active at this time, when it certainly isnt on the real aircraft (Minor issue).After lift-off, the autopilot flew in VNAV mode. The FMC showed ACT 225kts climb, when it should have shown ACT 165kts climb (before reaching acceleration altitude (Minor issue).Sometimes during climbout I switched to the FO-Side and was surprised by the FMA in the upper EICAS being boxed (for a short while). This boxing is triggered by aquiring a new mode, but should have been past for a while, clearly it

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Guest

very interesting to read your comments Jan. I wish I had a job flying the real thing, she is an amazing aircraft!

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Guest A32X

Great to hear from a Real 744 Driver.-Paul

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Guest thscholz

>I heard it a few times (only in the simulator, fortunately).>>>Jan "Janov"Das hoffe ich doch!;-) Thanks for these observations from a professional.CheersThomas

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Guest Just747-400

Dear Janov,Just a few issues:After lift-off, the autopilot flew in VNAV mode. The FMC showed ACT 225kts climb, when it should have shown ACT 165kts climb (before reaching acceleration altitude (Minor issue). On ours and the FANS FMS book it says that during t.o. phase ACT xxx KT reflects the limit speeds for the flap position of the aircraft up to acceleration, then the legend will change to ACT xxx KT for a clean configuration speed based on gross weight.Reaching the entered cruising altitude I deliberately entered a higher flight-level on the MCP-altitude. IIRC there should be a "check altitude target" caution after a while, but that could be triggered by a different setup, also, not sure. On ours and what the book says is that you will get this msg if the a/c is in between the MCP and FMC target altitude, nothing above.Regarding the C.I. I just took examples when flying and compared to our tables and they matched, maybe we have different engines, I don

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Hi Alex,thanks for your quick answers.Regarding the ACT CLMB: I am sure that the FMC shows the actual commanded FMC speed (also where the bug is at that time), which is V2+10 or airspeed at rotation (pitch more than 2 degrees). If a higher airspeed than that is flown for more than 5 seconds, that airspeed will become the new target, up to V2+25. Only after reaching acceleration height (1000 or 1500feet, dependend on type of departure) will the commanded speed go to next flap placard -5 kts. I can look up and quote from my AOM if required for clarification.Thanks for clarification about the other issues, we have the CF6-80C2-B1F engines on our aircraft. Maybe thats where the C.I. discrepancy stems from.You guys are doing a great job, thanks again!Jan "Janov"

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Guest Just747-400

Thank you for the kind words.

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Guest D17S

Hi Janov, This is terrific detail. Thanks for taking the time. It

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Guest Just747-400

Hi Sam,I would like to clarify about this V2, On Boeing manual and SOP we set MCP SPD @ V2 and thenAFDS Pitch CommandsAfter takeoff, the AFDS commands a pitch attitude which is the lesser of 15 degrees or below the Pitch Limit Indicator. As the rate of climb increases, the AFDS transitions from pitch angle to airspeed. Commanded speed is IAS/MACH Window (V2) plus 10 knots. If the airspeed exceeds V2+10 for more than 5 seconds, the target airspeed is reset to the current airspeed if it is less than V2+25 knots.VNAV SPD commands a climb at V2+10 to V2+25 knots. Autothrottle mode is THR REF and the reference thrust limit is takeoff.With correct takeoff parameters, the FMC commands the selected takeoff thrust when the TO/GA switch is pushed. During takeoff roll, autothrottle commands thrust and the FMC commands acceleration to between V2+10 and V2+25 knots,based on rate of rotation.

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Hi Sam,just to chime in with Alex and clarify: The Speed set in the MCP-Window at Take-off is V2 without additionals. The FMC will however, shortly after liftoff, set the speed-bug (on the speed-tape) to V2+10 or speed at rotation (if thats higher, not for slower or ealier rotations). It will then adjust that speed as mentioned - it will not change the speed dialed in in the MCP-Window, the only reference to this will be on the FMC VNAV page, where the ACT XXX CLMB is shown. The FD will show pitch commands to achieve those speeds.Not to confuse anyone any further, but if an engine failure is sensed, FD will command pitch to maintain V2 if airspeed is below V2, existing speed if speed is between V2 and V2+10 and V2+10 is airspeed is currently above that. Haven

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Guest D17S

Thanks for your response. I really enjoy the discussion. Focusing on the TOGA mode (pre-Vnav engagement) pitch logic for a moment: You described,

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Guest D17S

Hey Jan, Just got you response. This is great stuff, isn

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Thanks for mentioning that, Ryan. I think its great how PMDG has managed to work around a lot of limitations of MSFS, but certainly some just cant be overcome...As for the V2- Discussion, I really don

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