Vref - Slatted v Non Slatted Wing
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Vref - Slatted v Non Slatted Wing
Comparing G650 v Global of similar size
What's the typical Vref of a G650. How does that compare to the slatted wing of the Globals.
is the added complexity & weight of the slat system worth it. It seems that most largish jets are being designed with fixed leading edges.
is there any significant differences in handling qualities between the two jets in take-off and landing configuration.
What's the typical Vref of a G650. How does that compare to the slatted wing of the Globals.
is the added complexity & weight of the slat system worth it. It seems that most largish jets are being designed with fixed leading edges.
is there any significant differences in handling qualities between the two jets in take-off and landing configuration.
The G650 achieves an amazingly low Vref for a non-slatted wing - certainly no more than 10 kts faster than a Global for the same weight.
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Well, one reply. Pprune has certainly changed. 10 years ago one would ask a question and you would get a dozens or responses in a matter of hours from people who really knew their subject. Those times are long gone. No experts around here any more.
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Hi,
Most of the time Vref on G650 is about 118kt (about 6000lbs fuel load, 6-8 pax). Vapp is +5kt and is more than sufficient. No need to add extra for wind unless its really gusty.
Most of the time Vref on G650 is about 118kt (about 6000lbs fuel load, 6-8 pax). Vapp is +5kt and is more than sufficient. No need to add extra for wind unless its really gusty.
Yeah, rule of thumb you can do 110kts + payload and fuel. 6000 lbs is a comfortable arrival fuel with 118kts Vref as mentioned. Don't know about the Global, sorry.
Dreadfully sorry to disappoint you, Guptar.
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I’ve not flown both but have spoken to guys who have!
The 650 is nicer to fly on approach as it is much more responsive in roll - the Global can feel a bit wallowy at times!
This May be down to the slightly higher approach speeds, but much more likely to be that the Gulfstream wing is much stiffer. The Global wing is very flexible and gives a much more comfortable ride in the cruise...
If you want detailed perf comparisons, I have perf calculators for both types.
The 650 is nicer to fly on approach as it is much more responsive in roll - the Global can feel a bit wallowy at times!
This May be down to the slightly higher approach speeds, but much more likely to be that the Gulfstream wing is much stiffer. The Global wing is very flexible and gives a much more comfortable ride in the cruise...
If you want detailed perf comparisons, I have perf calculators for both types.
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So you ask a specific question about 2 types that are not exactly "Volkscrafts" - not 5 of em on every airport - that would require a person to answer it correctly to have flown both and then you whine about no answer ?
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Aircraft with slats/leading edge devices are certified to 1.23 Vs = REF as opposed to 1.33 Vs = REF for those with just flaps, under CS-25.
That will help massively with performance figures....
As for the thewrongtrousers, I'm sure that more than one person has changed account on here at some stage!
That will help massively with performance figures....
As for the thewrongtrousers, I'm sure that more than one person has changed account on here at some stage!
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Aircraft with slats/leading edge devices are certified to 1.23 Vs = REF as opposed to 1.33 Vs = REF for those with just flaps, under CS-25.
That will help massively with performance figures....
As for the thewrongtrousers, I'm sure that more than one person has changed account on here at some stage!
That will help massively with performance figures....
As for the thewrongtrousers, I'm sure that more than one person has changed account on here at some stage!
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The question of 1.23 VSr vs 1.3 Vs for the minimum speed for Vref depends on the amendment standard of the rules at the time of applying for cert, plus any issue papers that may have shown up. It's got nothing to do, as has been stated, with any specific design feature (slats, FBW, whatever)
Note that this is only ONE of several minimum criteria for Vref. It doesn't always follow that Vref is set at this specific minimum
Note that this is only ONE of several minimum criteria for Vref. It doesn't always follow that Vref is set at this specific minimum