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Slick9

Couple of things...

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I flew United's Capital One flight this weekend Washington KIAD to Beijing ZBAA. Incidentally about two hours after takeoff I was watching the news and was amazed to see CNN broadcasting that the real Capital One flight was returning to KIAD after losing an engine. It all ended well though.The real flight 897 departs KIAD at 12:23 and arrives ZBAA @ 13:55. I departed KIAD on time @ 12:23 and arrived at the gate in Beijing @ 13:45. Once again I am pretty impressed with the PMDG 744. Now I have a question, under what conditions would a pilot select to use a faster landing speed with the queen, ie. flaps 25 instead of 30? Does a faster approach speed give better handling in a crosswind?thanks Richard

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It really depends on the airline. Usually if you're light enough, there are no tailwinds, and you have good visibility, you could use flaps 25. I know certain airlines like British Airways use Flaps 30 as a requirement for safety. Qantas used to prefer Flap 25 and also Idle Reverse to extend the life of the breaks and reduce the stress on the flaps. I don't know if they still do. I prefer Flap 25 as I find it easier to control the aircraft on final. Controlling the speed is easier with Flap 30 though.Nice job on the flight. I noticed it's pretty difficult to come in behind schedule. Once I flew from EGLL and landed in WSSS a bit over half an hour early. Since I like Long Haul routes (don't ask me why), I think I'll give this one a go when I have time.Ryan GamurotLucky to live Hawai'ihttp://www.virtualpilots.org/signatures/vpa296.png

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I don't believe it depends on crosswind, a nice steady crosswind is quite easy to fly on final. There are considerations given to gusts, but it has to do with maintaining safe margins.I do believe less flaps would be warranted if landing weight is light, which lowers the Vref. All things considered, it is a comprimise between landing slow (to use less runway and less wear on gear) and less flap (less fuel and easier to transition to go around). These considerations are fairly universal to all types of aircraft. There might be Queen-specific issues, but I'm not aware of them (yet).


Dan Downs KCRP

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"Qantas used to prefer Flap 25 and also Idle Reverse to extend the life of the brakes and reduce the stress on the flaps."It was proved that carbon brakes lasted longer if they were heated up above a certain temperature. However, I'm not 100% sure that flaps 25 and idle reverse was chosen because of this. There are a number of reasons for Flap25/Idle reverse: Flaps 25 generates less noise pollution and less fuel usage. Idle reverse was also used for noise reduction and to reduce wear on the engine reverser mechanisms. Note: The airline's manuals, AFAIK, always contained a statement that full reverse could be used when deemed necessary.Qantas changed to flaps 30 for most landings after the Bangkok accident, but I think it was a knee-jerk reaction however. There were a number of important factors involved in the accident, including CRM (crew resource management) issues.Cheers.Q>

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