Derate V1 and VR for the new take-off tables?

[CPA156 0]

Hey AllI have been wondering how to get the V1 and VR speeds when using Derates (TO1/TO2) for the new tables that came with the 744F. They only have the tables for Maximum Rated Thrust. Are we supposed to use the ref speeds in the FMC when derating?

[rsrandazzo 6,353]

Patrick-Yes...always use the speeds in the FMC unless you have a reason to alter them...On the airplane, the performance manuals for most airlines are rarely touched- as the airlines operate in/out of the same fields constantly- and the performance information is included in the dispatch pre-departure plan.The only time you wind up using the performance manuals is if your company didn't provide you with the pre-departure plan- or if you are operating in/out of a field that you normally don't use.

[CPA156 0]

thanks Robert

[Guest SIX]

>Patrick->>Yes...always use the speeds in the FMC unless you have a>reason to alter them...>Hey,Not trying to argue or anything. I just wanted to make something clear in my experience.Situation:When the rwy is wet or when using derated TOPCAT usually sets the V1 at a much lower speed, sometimes by 20. This is to give plenty of room to abort. Now, on VR and V2 the FMC is usually very close. Conclusion:When I was watching the Virgin video, it seemed they had calculated all of this out and had it manually entered. After reading what you wrote here, is it safe to say that they calculate it all out for certian airports and let the FMC calc it out for others? I went to using TOPCAT because I was shown the vast difference the V1 is, at times from what the FMC calculates. It is a saftey thing I guess. Wilson HinesMy Blog: http://www.wilsonhines.com --------------------------------------http://www.precisionmanuals.com/images/forum/747400.jpghttp://www.precisionmanuals.com/images/forum/pmdg_744F.jpghttp://online.vatsimindicators.net/837438/3074.png

[Guest fullflapsplease]

I really think that is done in the video as just a way of showing you how they cross reference it with the FMC, don't forget, the way they worked it out using pressures, winds, temperatures, runways etc etc from manuals is already stored in the FMC, it's just a very complicated calculator, a paperless office if you like, saves the need for all those manuals ;)Mark.