Domino

Dear All Thanks for your interest, and feedbacks. Hi Vernon Yes you are right, firstly with your assumption PRH :-), and secondly with the computers. Hi Kyle I do not understand why, however, it`s clear now :-) -> Full name Michael Domenego

Hi Kevin The speeds the FMC gives you are for balanced field length and may well need adjusting for the conditions. They are a starting point, the FMC does not contain all the flight manual data. We speak about the PMDG 737, I am right? In the real airplane V1 needs only correction when: - Equipment is inoperative. - Runway is contaminated. - Unbalancing (Clearway > Stopway, Stopway > Clearway). DRY RUNWAY: • With actual ZFW and PLANNED TOF entered on PERF REF-page of the FMC, TAKEOFF REF-page 1/2 shows correct VR and V2 speeds. • With FMC/TAKEOFF REF-page 2/2 filled out correctly with actual wind and runway slope, TAKEOFF REF-page 1/2 shows balanced V1 corrected for VMCG. WET RUNWAY: • With actual ZFW and PLANNED TOF entered on PERF REF-page of the FMC, TAKEOFF REF-page 1/2 shows correct VR and V2 speeds. • If FMC/TAKEOFF REF-page 2/2 is filled out correctly with actual wind and runway slope, and RWY COND “WET” is highlighted, TAKEOFF REF-page 1/2 shows balanced V1WET corrected for VMCG. **************************** Hi Driver Don't use the FMC Takeoff Ref page 2. Only enter the EO ACC ALT and your ICAO proc A or B (thrust reduction alt and acceleration altitude) and then use TOPCAT for your V SPEEDS. FMC speeds may be used if they differ from the calculated TOPCAT speed by no more than 1 knot. Firstly I have not available the TOPCAT software, and it also not required to find out the correct takeoff speeds. Inputing values in such a tool and using the output makes life easier, thats right. However, without any background knowledge (knowing what is standing behind the automatic calculation), ... ,for me this makes no sense. When the procedure is known, determining the values by use of the tables is easy and takes only a few minutes :smile: **************************** PMDG team I would recommend to inhibit the wind correction feature (in case you do not want to correct the error). It do not make sense and is also not serious to simulate the reverse logic. Michael

Hi Pete For me, flying from A to B without knowledge about the real things does not make sense. Either I do it right or not at all. Hi Skelsey You are right, I wanted to complain about the error. I thought the PMDG team is interested. Maybe they can correct it with the next update. Michael

Hi Donor First of all thanks for your feedback. But, you got it wrong. Slope and Wind: - A runway upslope or headwind component affect the acceleration - a higher V1 is needed. - A runway downslope or tailwind component affect the deceleration - a lower V1 is needed. The value that V1 needs to be corrected for, is available in the FCOM/PI SLOPE AND WIND V1 ADJUSTMENTS table. Example: Aircraft type = B737-800W/CFM56-7B26 Condition = Wet Runway Weight = 80 (1000 KG) Wind = 20 kts headwind component Required V1 adjustement = V1 + 2 kts Michael

Dear All When a headwind is entered on TAKEOFF REF 2/2 page on line 1 left (LSK1L), the FMC decreases the V1 speed, why? A runway headwind component affect the acceleration, therefore the FMC should show a higher V1. Michael